flake

Set the minimun C++ standard for LBANN, Hydrogen, and DiHydrogen to
C++17.  The minumim C++ standard for Aluminum is C++14.  Add new
versions for Aluminum, Hydrogen, and DiHydrogen.  Added support for
high performance linkers in LBANN recipe (gold and lld).  Added
variants to LBANN for enabling embedded Python support independently
from the Python front end.

.codecov.yml

@@ -4,7 +4,8 @@ coverage:
   range: 60...90
   status:
     project:
-      default: yes
+      default:
+        threshold: 0.2%
 
 ignore:
   - lib/spack/spack/test/.*

.coveragerc

@@ -4,7 +4,9 @@
 parallel = True
 concurrency = multiprocessing
 branch = True
-source = lib
+source =
+     bin
+     lib
 omit =
      lib/spack/spack/test/*
      lib/spack/docs/*

.flake8

@@ -27,6 +27,47 @@
 # - N813: camelcase imported as lowercase
 # - N814: camelcase imported as constant
 #
+# F4: pyflakes import checks, these are now checked by mypy more precisely
+# - F403: from module import *
+# - F405: undefined name or from *
+#
+# Black ignores, these are incompatible with black style and do not follow PEP-8
+# - E203: white space around slice operators can be required, ignore : warn
+# - W503: see above, already ignored for line-breaks
+#
 [flake8]
-ignore = E129,E221,E241,E272,E731,W503,W504,F999,N801,N813,N814
-max-line-length = 79
+ignore = E129,E221,E241,E272,E731,W503,W504,F999,N801,N813,N814,F403,F405
+max-line-length = 88
+
+# F4: Import
+# - F405: `name` may be undefined, or undefined from star imports: `module`
+#
+# F8: Name
+# - F821: undefined name `name`
+#
+per-file-ignores =
+  var/spack/repos/*/package.py:F405,F821
+
+# exclude things we usually do not want linting for.
+# These still get linted when passed explicitly, as when spack flake8 passes
+# them on the command line.
+exclude =
+  .git
+  etc/
+  opt/
+  share/
+  var/spack/cache/
+  var/spack/gpg*/
+  var/spack/junit-report/
+  var/spack/mock-configs/
+  lib/spack/external
+  __pycache__
+  var
+
+format = spack
+
+[flake8:local-plugins]
+report =
+  spack = flake8_formatter:SpackFormatter
+paths =
+  ./share/spack/qa/

.flake8_packages

@@ -1,24 +0,0 @@
-# -*- conf -*-
-# flake8 settings for Spack package files.
-#
-# This should include all the same exceptions that we use for core files.
-#
-# In Spack packages, we also allow the single `from spack import *`
-# wildcard import and dependencies can set globals for their
-# dependents. So we add exceptions for checks related to undefined names.
-#
-# Note that we also add *per-line* exemptions for certain patterns in the
-# `spack flake8` command.  This is where F403 for `from spack import *`
-# is added (because we *only* allow that wildcard).
-#
-# See .flake8 for regular exceptions.
-#
-# F4: Import
-# - F405: `name` may be undefined, or undefined from star imports: `module`
-#
-# F8: Name
-# - F821: undefined name `name`
-#
-[flake8]
-ignore = E129,E221,E241,E272,E731,W503,W504,F405,F821,F999,N801,N813,N814
-max-line-length = 79

.gitattributes

@@ -1 +1,3 @@
 *.py diff=python
+*.lp linguist-language=Prolog
+lib/spack/external/* linguist-vendored

.github/actions/add-maintainers-as-reviewers/entrypoint.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 #
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)

.github/dependabot.yml

@@ -0,0 +1,7 @@
+version: 2
+updates:
+  # Maintain dependencies for GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "daily"

.github/workflows/install_spack.sh

@@ -1,5 +1,20 @@
 #!/usr/bin/env sh
-git clone https://github.com/spack/spack.git
-echo -e "config:\n  build_jobs: 2" > spack/etc/spack/config.yaml
-. spack/share/spack/setup-env.sh
-spack compilers
+. share/spack/setup-env.sh
+echo -e "config:\n  build_jobs: 2" > etc/spack/config.yaml
+spack config add "packages:all:target:[x86_64]"
+# TODO: remove this explicit setting once apple-clang detection is fixed
+cat <<EOF > etc/spack/compilers.yaml
+compilers:
+- compiler:
+    spec: apple-clang@11.0.3
+    paths:
+      cc: /usr/bin/clang
+      cxx: /usr/bin/clang++
+      f77: /usr/local/bin/gfortran-9
+      fc: /usr/local/bin/gfortran-9
+    modules: []
+    operating_system: catalina
+    target: x86_64
+EOF
+spack compiler info apple-clang
+spack debug report

.github/workflows/linux_build_tests.yaml

@@ -3,13 +3,12 @@ name: linux builds
 on:
   push:
     branches:
-    - master
     - develop
     - releases/**
   pull_request:
     branches:
-    - master
     - develop
+    - releases/**
     paths-ignore:
       # Don't run if we only modified packages in the built-in repository
       - 'var/spack/repos/builtin/**'
@@ -19,36 +18,41 @@ on:
       - '!var/spack/repos/builtin/packages/py-setuptools/**'
       - '!var/spack/repos/builtin/packages/openjpeg/**'
       - '!var/spack/repos/builtin/packages/r-rcpp/**'
+      - '!var/spack/repos/builtin/packages/ruby-rake/**'
       # Don't run if we only modified documentation
       - 'lib/spack/docs/**'
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
     strategy:
-      max-parallel: 4
       matrix:
-        package: [lz4, mpich, tut, py-setuptools, openjpeg, r-rcpp]
+        package:
+        - lz4  # MakefilePackage
+        - mpich~fortran  # AutotoolsPackage
+        - tut  # WafPackage
+        - py-setuptools  # PythonPackage
+        - openjpeg  # CMakePackage
+        - r-rcpp  # RPackage
+        - ruby-rake  # RubyPackage
     steps:
     - uses: actions/checkout@v2
-    - name: Cache ccache's store
-      uses: actions/cache@v1
+    - uses: actions/cache@v2.1.4
       with:
         path: ~/.ccache
         key: ccache-build-${{ matrix.package }}
         restore-keys: |
           ccache-build-${{ matrix.package }}
-    - name: Setup Python
-      uses: actions/setup-python@v1
+    - uses: actions/setup-python@v2
       with:
-        python-version: 3.8
+        python-version: 3.9
     - name: Install System Packages
       run: |
         sudo apt-get update
-        sudo apt-get -yqq install ccache gfortran perl perl-base r-base r-base-core r-base-dev findutils openssl libssl-dev libpciaccess-dev
+        sudo apt-get -yqq install ccache gfortran perl perl-base r-base r-base-core r-base-dev ruby findutils openssl libssl-dev libpciaccess-dev
         R --version
         perl --version
+        ruby --version
     - name: Copy Configuration
       run: |
         ccache -M 300M && ccache -z

.github/workflows/linux_unit_tests.yaml

@@ -3,32 +3,35 @@ name: linux tests
 on:
   push:
     branches:
-      - master
       - develop
       - releases/**
   pull_request:
     branches:
-      - master
       - develop
+      - releases/**
 jobs:
   unittests:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [2.7, 3.5, 3.6, 3.7, 3.8]
+        python-version: [2.7, 3.5, 3.6, 3.7, 3.8, 3.9]
 
     steps:
     - uses: actions/checkout@v2
-    - name: Setup Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      with:
+        fetch-depth: 0
+    - uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install System packages
       run: |
           sudo apt-get -y update
-          sudo apt-get install -y coreutils gfortran graphviz gnupg2 mercurial ninja-build patchelf
+          # Needed for unit tests
+          sudo apt-get install -y coreutils gfortran graphviz gnupg2 mercurial
+          sudo apt-get install -y ninja-build patchelf
           # Needed for kcov
-          sudo apt-get -y install cmake binutils-dev libcurl4-openssl-dev zlib1g-dev libdw-dev libiberty-dev
+          sudo apt-get -y install cmake binutils-dev libcurl4-openssl-dev
+          sudo apt-get -y install zlib1g-dev libdw-dev libiberty-dev
     - name: Install Python packages
       run: |
           pip install --upgrade pip six setuptools codecov coverage
@@ -36,9 +39,7 @@ jobs:
       run: |
           # Need this for the git tests to succeed.
           git --version
-          git config --global user.email "spack@example.com"
-          git config --global user.name "Test User"
-          git fetch -u origin develop:develop
+          . .github/workflows/setup_git.sh
     - name: Install kcov for bash script coverage
       env:
           KCOV_VERSION: 34
@@ -56,7 +57,111 @@ jobs:
           share/spack/qa/run-unit-tests
           coverage combine
           coverage xml
-    - name: Upload to codecov.io
-      uses: codecov/codecov-action@v1
+    - uses: codecov/codecov-action@v1
       with:
         flags: unittests,linux
+  shell:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 0
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
+    - name: Install System packages
+      run: |
+          sudo apt-get -y update
+          # Needed for shell tests
+          sudo apt-get install -y coreutils csh zsh tcsh fish dash bash
+          # Needed for kcov
+          sudo apt-get -y install cmake binutils-dev libcurl4-openssl-dev
+          sudo apt-get -y install zlib1g-dev libdw-dev libiberty-dev
+    - name: Install Python packages
+      run: |
+          pip install --upgrade pip six setuptools codecov coverage
+    - name: Setup git configuration
+      run: |
+          # Need this for the git tests to succeed.
+          git --version
+          . .github/workflows/setup_git.sh
+    - name: Install kcov for bash script coverage
+      env:
+          KCOV_VERSION: 38
+      run: |
+          KCOV_ROOT=$(mktemp -d)
+          wget --output-document=${KCOV_ROOT}/${KCOV_VERSION}.tar.gz https://github.com/SimonKagstrom/kcov/archive/v${KCOV_VERSION}.tar.gz
+          tar -C ${KCOV_ROOT} -xzvf ${KCOV_ROOT}/${KCOV_VERSION}.tar.gz
+          mkdir -p ${KCOV_ROOT}/build
+          cd ${KCOV_ROOT}/build && cmake -Wno-dev ${KCOV_ROOT}/kcov-${KCOV_VERSION} && cd -
+          make -C ${KCOV_ROOT}/build && sudo  make -C ${KCOV_ROOT}/build install
+    - name: Run shell tests
+      env:
+          COVERAGE: true
+      run: |
+          share/spack/qa/run-shell-tests
+    - uses: codecov/codecov-action@v1
+      with:
+        flags: shelltests,linux
+
+  centos6:
+    # Test for Python2.6 run on Centos 6
+    runs-on: ubuntu-latest
+    container: spack/github-actions:centos6
+    steps:
+    - name: Run unit tests
+      env:
+          HOME: /home/spack-test
+      run: |
+          whoami && echo $HOME && cd $HOME
+          git clone https://github.com/spack/spack.git && cd spack
+          git fetch origin ${{ github.ref }}:test-branch
+          git checkout test-branch
+          share/spack/qa/run-unit-tests
+
+  rhel8-platform-python:
+    runs-on: ubuntu-latest
+    container: registry.access.redhat.com/ubi8/ubi
+    steps:
+    - name: Install dependencies
+      run: |
+          dnf install -y \
+              bzip2 curl file gcc-c++ gcc gcc-gfortran git gnupg2 gzip \
+              make patch tcl unzip which xz
+    - uses: actions/checkout@v2
+    - name: Setup repo and non-root user
+      run: |
+          git --version
+          git fetch --unshallow
+          . .github/workflows/setup_git.sh
+          useradd spack-test
+          chown -R spack-test .
+    - name: Run unit tests
+      env:
+          SPACK_PYTHON: /usr/libexec/platform-python
+      shell: runuser -u spack-test -- bash {0}
+      run: |
+          source share/spack/setup-env.sh
+          spack unit-test -k 'not svn and not hg' -x --verbose
+
+  clingo:
+    # Test for the clingo based solver
+    runs-on: ubuntu-latest
+    container: spack/github-actions:clingo
+    steps:
+      - name: Run unit tests
+        run: |
+          whoami && echo PWD=$PWD && echo HOME=$HOME && echo SPACK_TEST_SOLVER=$SPACK_TEST_SOLVER
+          which clingo && clingo --version
+          git clone https://github.com/spack/spack.git && cd spack
+          git fetch origin ${{ github.ref }}:test-branch
+          git checkout test-branch
+          . share/spack/setup-env.sh
+          spack compiler find
+          spack solve mpileaks%gcc
+          coverage run $(which spack) unit-test -v
+          coverage combine
+          coverage xml
+      - uses: codecov/codecov-action@v1
+        with:
+          flags: unittests,linux,clingo

.github/workflows/macos_python.yml

@@ -8,6 +8,13 @@ on:
   schedule:
     # nightly at 1 AM
     - cron: '0 1 * * *'
+  pull_request:
+    branches:
+    - develop
+    paths:
+      # Run if we modify this yaml file
+      - '.github/workflows/macos_python.yml'
+      # TODO: run if we touch any of the recipes involved in this
 
 # GitHub Action Limits
 # https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
@@ -18,10 +25,14 @@ jobs:
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v2
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
     - name: spack install
       run: |
         . .github/workflows/install_spack.sh
-        spack install -v gcc
+        # 9.2.0 is the latest version on which we apply homebrew patch
+        spack install -v --fail-fast gcc@9.2.0 %apple-clang
 
   install_jupyter_clang:
     name: jupyter
@@ -29,30 +40,39 @@ jobs:
     timeout-minutes: 700
     steps:
     - uses: actions/checkout@v2
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
     - name: spack install
       run: |
         . .github/workflows/install_spack.sh
-        spack install -v py-jupyter %clang
+        spack install -v --fail-fast py-jupyterlab %apple-clang
 
   install_scipy_clang:
     name: scipy, mpl, pd
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v2
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
     - name: spack install
       run: |
         . .github/workflows/install_spack.sh
-        spack install -v py-scipy %clang
-        spack install -v py-matplotlib %clang
-        spack install -v py-pandas %clang
+        spack install -v --fail-fast py-scipy %apple-clang
+        spack install -v --fail-fast py-matplotlib %apple-clang
+        spack install -v --fail-fast py-pandas %apple-clang
 
   install_mpi4py_clang:
     name: mpi4py, petsc4py
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v2
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
     - name: spack install
       run: |
         . .github/workflows/install_spack.sh
-        spack install -v py-mpi4py %clang
-        spack install -v py-petsc4py %clang
+        spack install -v --fail-fast py-mpi4py %apple-clang
+        spack install -v --fail-fast py-petsc4py %apple-clang

.github/workflows/macos_unit_tests.yaml

@@ -3,47 +3,42 @@ name: macos tests
 on:
   push:
     branches:
-      - master
       - develop
       - releases/**
   pull_request:
     branches:
-      - master
       - develop
+      - releases/**
 jobs:
   build:
-
     runs-on: macos-latest
     strategy:
       matrix:
-        python-version: [3.7]
-
+        python-version: [3.8]
     steps:
     - uses: actions/checkout@v2
-    - name: Setup Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      with:
+        fetch-depth: 0
+    - uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install Python packages
       run: |
           pip install --upgrade pip six setuptools
           pip install --upgrade codecov coverage
-          pip install --upgrade flake8 pep8-naming
+          pip install --upgrade flake8 pep8-naming mypy
     - name: Setup Homebrew packages
       run: |
-        brew update
-        brew upgrade
-        brew install gcc gnupg2 dash kcov
+        brew install dash fish gcc gnupg2 kcov
     - name: Run unit tests
       run: |
         git --version
-        git fetch -u origin develop:develop
+        . .github/workflows/setup_git.sh
         . share/spack/setup-env.sh
-        coverage run $(which spack) test
+        coverage run $(which spack) unit-test
         coverage combine
         coverage xml
-    - name: Upload to codecov.io
-      uses: codecov/codecov-action@v1
+    - uses: codecov/codecov-action@v1
       with:
         file: ./coverage.xml
         flags: unittests,macos

.github/workflows/minimum_python_versions.yaml

@@ -1,31 +0,0 @@
-name: python version check
-
-on:
-  push:
-    branches:
-      - master
-      - develop
-      - releases/**
-  pull_request:
-    branches:
-      - master
-      - develop
-jobs:
-  validate:
-
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/checkout@v2
-    - name: Setup Python
-      uses: actions/setup-python@v1
-      with:
-        python-version: 3.7
-    - name: Install Python Packages
-      run: |
-        pip install --upgrade pip
-        pip install --upgrade vermin
-    - name: Minimum Version (Spack's Core)
-      run: vermin --backport argparse -t=2.6- -t=3.5- -v lib/spack/spack/ lib/spack/llnl/ bin/
-    - name: Minimum Version (Repositories)
-      run: vermin --backport argparse -t=2.6- -t=3.5- -v var/spack/repos

.github/workflows/setup_git.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env sh
+git config --global user.email "spack@example.com"
+git config --global user.name "Test User"
+# With fetch-depth: 0 we have a remote develop
+# but not a local branch. Don't do this on develop
+if [ "$(git branch --show-current)" != "develop" ]
+then
+  git branch develop origin/develop
+fi

.github/workflows/style_and_docs.yaml

@@ -0,0 +1,65 @@
+name: style and docs
+
+on:
+  push:
+    branches:
+      - develop
+      - releases/**
+  pull_request:
+    branches:
+      - develop
+      - releases/**
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
+    - name: Install Python Packages
+      run: |
+        pip install --upgrade pip
+        pip install --upgrade vermin
+    - name: Minimum Version (Spack's Core)
+      run: vermin --backport argparse --backport typing -t=2.6- -t=3.5- -v lib/spack/spack/ lib/spack/llnl/ bin/
+    - name: Minimum Version (Repositories)
+      run: vermin --backport argparse --backport typing -t=2.6- -t=3.5- -v var/spack/repos
+  style:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 0
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
+    - name: Install Python packages
+      run: |
+        pip install --upgrade pip six setuptools flake8 mypy>=0.800 black
+    - name: Setup git configuration
+      run: |
+        # Need this for the git tests to succeed.
+        git --version
+        . .github/workflows/setup_git.sh
+    - name: Run style tests
+      run: |
+          share/spack/qa/run-style-tests
+  documentation:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
+    - name: Install System packages
+      run: |
+        sudo apt-get -y update
+        sudo apt-get install -y coreutils ninja-build graphviz
+    - name: Install Python packages
+      run: |
+        pip install --upgrade pip six setuptools
+        pip install --upgrade -r lib/spack/docs/requirements.txt
+    - name: Build documentation
+      run: |
+          share/spack/qa/run-doc-tests

.gitignore

@@ -1,40 +1,511 @@
-/db
+##########################
+# Spack-specific ignores #
+##########################
+
 /var/spack/stage
 /var/spack/cache
 /var/spack/environments
 /var/spack/repos/*/index.yaml
 /var/spack/repos/*/lock
-__pycache__/
-*.pyc
 /opt
-*~
-.DS_Store
-.idea
 # Ignore everything in /etc/spack except /etc/spack/defaults
 /etc/spack/*
 !/etc/spack/defaults
-/etc/spackconfig
-/share/spack/dotkit
 /share/spack/modules
 /share/spack/lmod
-/TAGS
-*.swp
-/htmlcov
-.coverage
-\#*
-.#*
-.cache
-lib/spack/spack/test/.cache
-/bin/spackc
+# Debug logs
+spack-db.*
 *.in.log
 *.out.log
-*.orig
 
-# Eclipse files
-.project
+###########################
+# Python-specific ignores #
+###########################
+
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+#lib/
+#lib64/
+parts/
+sdist/
+#var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+########################
+# Vim-specific ignores #
+########################
+
+# Swap
+[._]*.s[a-v][a-z]
+!*.svg  # comment out if you don't need vector files
+[._]*.sw[a-p]
+[._]s[a-rt-v][a-z]
+[._]ss[a-gi-z]
+[._]sw[a-p]
+
+# Session
+Session.vim
+Sessionx.vim
+
+# Temporary
+.netrwhist
+*~
+# Auto-generated tag files
+tags
+# Persistent undo
+[._]*.un~
+
+##########################
+# Emacs-specific ignores #
+##########################
+
+*~
+\#*\#
+/.emacs.desktop
+/.emacs.desktop.lock
+*.elc
+auto-save-list
+tramp
+.\#*
+
+# Org-mode
+.org-id-locations
+*_archive
+
+# flymake-mode
+*_flymake.*
+
+# eshell files
+/eshell/history
+/eshell/lastdir
+
+# elpa packages
+/elpa/
+
+# reftex files
+*.rel
+
+# AUCTeX auto folder
+/auto/
+
+# cask packages
+.cask/
+dist/
+
+# Flycheck
+flycheck_*.el
+
+# server auth directory
+/server/
+
+# projectiles files
+.projectile
+
+# directory configuration
+.dir-locals.el
+
+# network security
+/network-security.data
+
+############################
+# Eclipse-specific ignores #
+############################
+
+.metadata
+#bin/
+tmp/
+*.tmp
+*.bak
+*.swp
+*~.nib
+local.properties
+.settings/
+.loadpath
+.recommenders
+
+# External tool builders
+.externalToolBuilders/
+
+# Locally stored "Eclipse launch configurations"
+*.launch
+
+# PyDev specific (Python IDE for Eclipse)
+*.pydevproject
+
+# CDT-specific (C/C++ Development Tooling)
 .cproject
-.pydevproject
 
-# VSCode files
-.vscode
-.devcontainer
+# CDT- autotools
+.autotools
+
+# Java annotation processor (APT)
+.factorypath
+
+# PDT-specific (PHP Development Tools)
+.buildpath
+
+# sbteclipse plugin
+.target
+
+# Tern plugin
+.tern-project
+
+# TeXlipse plugin
+.texlipse
+
+# STS (Spring Tool Suite)
+.springBeans
+
+# Code Recommenders
+.recommenders/
+
+# Annotation Processing
+.apt_generated/
+.apt_generated_test/
+
+# Scala IDE specific (Scala & Java development for Eclipse)
+.cache-main
+.scala_dependencies
+.worksheet
+
+# Uncomment this line if you wish to ignore the project description file.
+# Typically, this file would be tracked if it contains build/dependency configurations:
+#.project
+
+##################################
+# Visual Studio-specific ignores #
+##################################
+
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+*.code-workspace
+
+# Local History for Visual Studio Code
+.history/
+
+#################################
+# Sublime Text-specific ignores #
+#################################
+
+# Cache files for Sublime Text
+*.tmlanguage.cache
+*.tmPreferences.cache
+*.stTheme.cache
+
+# Workspace files are user-specific
+*.sublime-workspace
+
+# Project files should be checked into the repository, unless a significant
+# proportion of contributors will probably not be using Sublime Text
+# *.sublime-project
+
+# SFTP configuration file
+sftp-config.json
+sftp-config-alt*.json
+
+# Package control specific files
+Package Control.last-run
+Package Control.ca-list
+Package Control.ca-bundle
+Package Control.system-ca-bundle
+Package Control.cache/
+Package Control.ca-certs/
+Package Control.merged-ca-bundle
+Package Control.user-ca-bundle
+oscrypto-ca-bundle.crt
+bh_unicode_properties.cache
+
+# Sublime-github package stores a github token in this file
+# https://packagecontrol.io/packages/sublime-github
+GitHub.sublime-settings
+
+##############################
+# JetBrains-specific ignores #
+##############################
+
+# Ignore the entire folder since it may conatin more files than
+# just the ones listed below
+.idea/
+
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/artifacts
+# .idea/compiler.xml
+# .idea/jarRepositories.xml
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+##########################
+# macOS-specific ignores #
+##########################
+
+# General
+.DS_Store
+.AppleDouble
+.LSOverride
+
+# Icon must end with two \r
+Icon
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
+
+##########################
+# Linux-specific ignores #
+##########################
+
+*~
+
+# temporary files which can be created if a process still has a handle open of a deleted file
+.fuse_hidden*
+
+# KDE directory preferences
+.directory
+
+# Linux trash folder which might appear on any partition or disk
+.Trash-*
+
+# .nfs files are created when an open file is removed but is still being accessed
+.nfs*
+
+############################
+# Windows-specific ignores #
+############################
+
+# Windows thumbnail cache files
+Thumbs.db
+Thumbs.db:encryptable
+ehthumbs.db
+ehthumbs_vista.db
+
+# Dump file
+*.stackdump
+
+# Folder config file
+[Dd]esktop.ini
+
+# Recycle Bin used on file shares
+$RECYCLE.BIN/
+
+# Windows Installer files
+*.cab
+*.msi
+*.msix
+*.msm
+*.msp
+
+# Windows shortcuts
+*.lnk

.mailmap

@@ -20,8 +20,8 @@ Geoffrey Oxberry      <oxberry1@llnl.gov>               Geoffrey Oxberry
 Glenn Johnson         <glenn-johnson@uiowa.edu>         Glenn Johnson           <gjohnson@argon-ohpc.hpc.uiowa.edu>
 Glenn Johnson         <glenn-johnson@uiowa.edu>         Glenn Johnson           <glennpj@gmail.com>
 Gregory Becker        <becker33@llnl.gov>               Gregory Becker          <becker33.llnl.gov>
-Gregory Becker        <becker33@llnl.gov>               becker33                <becker33.llnl.gov>
-Gregory Becker        <becker33@llnl.gov>               becker33                <becker33@llnl.gov>
+Gregory Becker        <becker33@llnl.gov>               Gregory Becker          <becker33.llnl.gov>
+Gregory Becker        <becker33@llnl.gov>               Gregory Becker          <becker33@llnl.gov>
 Gregory L. Lee        <lee218@llnl.gov>                 Greg Lee                <lee218@llnl.gov>
 Gregory L. Lee        <lee218@llnl.gov>                 Gregory L. Lee          <lee218@cab687.llnl.gov>
 Gregory L. Lee        <lee218@llnl.gov>                 Gregory L. Lee          <lee218@cab690.llnl.gov>

.mypy.ini

@@ -0,0 +1,35 @@
+[mypy]
+python_version = 3.7
+files=lib/spack/llnl/**/*.py,lib/spack/spack/**/*.py
+mypy_path=bin,lib/spack,lib/spack/external,var/spack/repos/builtin
+# This and a generated import file allows supporting packages
+namespace_packages=True
+# To avoid re-factoring all the externals, ignore errors and missing imports
+# globally, then turn back on in spack and spack submodules
+ignore_errors=True
+ignore_missing_imports=True
+
+[mypy-spack.*]
+ignore_errors=False
+ignore_missing_imports=False
+
+[mypy-packages.*]
+ignore_errors=False
+ignore_missing_imports=False
+
+[mypy-llnl.*]
+ignore_errors=False
+ignore_missing_imports=False
+
+[mypy-spack.test.packages]
+ignore_errors=True
+
+# ignore errors in fake import path for packages
+[mypy-spack.pkg.*]
+ignore_errors=True
+ignore_missing_imports=True
+
+# jinja has syntax in it that requires python3 and causes a parse error
+# skip importing it
+[mypy-jinja2]
+follow_imports=skip

.travis.yml

@@ -1,152 +0,0 @@
-#=============================================================================
-# Project settings
-#=============================================================================
-# Only build master and develop on push; do not build every branch.
-branches:
-  only:
-    - master
-    - develop
-    - /^releases\/.*$/
-
-#=============================================================================
-# Build matrix
-#=============================================================================
-
-dist: bionic
-
-jobs:
-  fast_finish: true
-  include:
-    - stage: 'style checks'
-      python: '3.8'
-      os: linux
-      language: python
-      env: TEST_SUITE=flake8
-    - stage: 'unit tests + documentation'
-      python: '2.6'
-      dist: trusty
-      os: linux
-      language: python
-      addons:
-        apt:
-          # Everything but patchelf, that is not available for trusty
-          packages:
-            - ccache
-            - gfortran
-            - graphviz
-            - gnupg2
-            - kcov
-            - mercurial
-            - ninja-build
-            - realpath
-            - zsh
-            - fish
-      env: [ TEST_SUITE=unit, COVERAGE=true ]
-    - python: '3.8'
-      os: linux
-      language: python
-      env: [ TEST_SUITE=shell, COVERAGE=true, KCOV_VERSION=38 ]
-    - python: '3.8'
-      os: linux
-      language: python
-      env: TEST_SUITE=doc
-
-stages:
-  - 'style checks'
-  - 'unit tests + documentation'
-
-
-#=============================================================================
-# Environment
-#=============================================================================
-
-# Docs need graphviz to build
-addons:
-  # for Linux builds, we use APT
-  apt:
-    packages:
-      - ccache
-      - coreutils
-      - gfortran
-      - graphviz
-      - gnupg2
-      - mercurial
-      - ninja-build
-      - patchelf
-      - zsh
-      - fish
-    update: true
-
-# ~/.ccache needs to be cached directly as Travis is not taking care of it
-# (possibly because we use 'language: python' and not 'language: c')
-cache:
-  pip: true
-  ccache: true
-  directories:
-    - ~/.ccache
-
-before_install:
-  - ccache -M 2G && ccache -z
-  # Install kcov manually, since it's not packaged for bionic beaver
-  - if [[ "$KCOV_VERSION" ]]; then
-        sudo apt-get -y install cmake binutils-dev libcurl4-openssl-dev zlib1g-dev libdw-dev libiberty-dev;
-        KCOV_ROOT=$(mktemp -d);
-        wget --output-document=${KCOV_ROOT}/${KCOV_VERSION}.tar.gz https://github.com/SimonKagstrom/kcov/archive/v${KCOV_VERSION}.tar.gz;
-        tar -C ${KCOV_ROOT} -xzvf ${KCOV_ROOT}/${KCOV_VERSION}.tar.gz;
-        mkdir -p ${KCOV_ROOT}/build;
-        cd ${KCOV_ROOT}/build && cmake -Wno-dev ${KCOV_ROOT}/kcov-${KCOV_VERSION} && cd - ;
-        make -C ${KCOV_ROOT}/build && sudo  make -C ${KCOV_ROOT}/build install;
-    fi
-
-# Install various dependencies
-install:
-  - pip install --upgrade pip
-  - pip install --upgrade six
-  - pip install --upgrade setuptools
-  - pip install --upgrade codecov coverage==4.5.4
-  - pip install --upgrade flake8
-  - pip install --upgrade pep8-naming
-  - if [[ "$TEST_SUITE" == "doc" ]]; then
-        pip install --upgrade -r lib/spack/docs/requirements.txt;
-    fi
-
-before_script:
-  # Need this for the git tests to succeed.
-  - git config --global user.email "spack@example.com"
-  - git config --global user.name "Test User"
-
-  # Need this to be able to compute the list of changed files
-  - git fetch origin ${TRAVIS_BRANCH}:${TRAVIS_BRANCH}
-
-#=============================================================================
-# Building
-#=============================================================================
-script:
-  - share/spack/qa/run-$TEST_SUITE-tests
-
-after_success:
-  - ccache -s
-  - case "$TEST_SUITE" in
-        unit)
-            if [[ "$COVERAGE" == "true" ]]; then
-                codecov --env PYTHON_VERSION
-                        --required
-                        --flags "${TEST_SUITE}${TRAVIS_OS_NAME}";
-            fi
-            ;;
-        shell)
-            codecov --env PYTHON_VERSION
-            --required
-            --flags "${TEST_SUITE}${TRAVIS_OS_NAME}";
-    esac
-
-#=============================================================================
-# Notifications
-#=============================================================================
-notifications:
-  email:
-    recipients:
-    - tgamblin@llnl.gov
-    - massimiliano.culpo@gmail.com
-    on_success: change
-    on_failure: always

CHANGELOG.md

@@ -1,3 +1,161 @@
+# v0.16.0 (2020-11-18)
+
+`v0.16.0` is a major feature release.
+
+## Major features in this release
+
+1. **New concretizer (experimental)** Our new backtracking concretizer is
+   now in Spack as an experimental feature. You will need to install
+   `clingo@master+python` and set `concretizer: clingo` in `config.yaml`
+   to use it. The original concretizer is not exhaustive and is not
+   guaranteed to find a solution if one exists. We encourage you to use
+   the new concretizer and to report any bugs you find with it. We
+   anticipate making the new concretizer the default and including all
+   required dependencies for it in Spack `v0.17`. For more details, see
+   #19501.
+
+2. **spack test (experimental)** Users can add `test()` methods to their
+   packages to run smoke tests on installations with the new `spack test`
+   command (the old `spack test` is now `spack unit-test`). `spack test`
+   is environment-aware, so you can `spack install` an environment and
+   `spack test run` smoke tests on all of its packages. Historical test
+   logs can be perused with `spack test results`. Generic smoke tests for
+   MPI implementations, C, C++, and Fortran compilers as well as specific
+   smoke tests for 18 packages. This is marked experimental because the
+   test API (`self.run_test()`) is likely to be change, but we encourage
+   users to upstream tests, and we will maintain and refactor any that
+   are added to mainline packages (#15702).
+
+3. **spack develop** New `spack develop` command allows you to develop
+   several packages at once within a Spack environment. Running
+   `spack develop foo@v1` and `spack develop bar@v2` will check
+    out specific versions of `foo` and `bar` into subdirectories, which you
+    can then build incrementally with `spack install ` (#15256).
+
+4. **More parallelism** Spack previously installed the dependencies of a
+   _single_ spec in parallel. Entire environments can now be installed in
+   parallel, greatly accelerating builds of large environments. get
+   parallelism from individual specs. Spack now parallelizes entire
+   environment builds (#18131).
+
+5. **Customizable base images for spack containerize**
+    `spack containerize` previously only output a `Dockerfile` based
+    on `ubuntu`. You may now specify any base image of your choosing (#15028).
+
+6. **more external finding** `spack external find` was added in `v0.15`,
+   but only `cmake` had support. `spack external find` can now find
+   `bison`, `cuda`, `findutils`, `flex`, `git`, `lustre` `m4`, `mpich`,
+   `mvapich2`, `ncurses`, `openmpi`, `perl`, `spectrum-mpi`, `tar`, and
+   `texinfo` on your system and add them automatically to
+   `packages.yaml`.
+
+7. **Support aocc, nvhpc, and oneapi compilers** We are aggressively
+   pursuing support for the newest vendor compilers, especially those for
+   the U.S. exascale and pre-exascale systems. Compiler classes and
+   auto-detection for `aocc`, `nvhpc`, `oneapi` are now in Spack (#19345,
+   #19294, #19330).
+
+## Additional new features of note
+
+* New `spack mark` command can be used to designate packages as explicitly
+  installed, so that `spack gc` will not garbage-collect them (#16662).
+* `install_tree` can be customized with Spack's projection format (#18341)
+* `sbang` now lives in the `install_tree` so that all users can access it (#11598)
+* `csh` and `tcsh` users no longer need to set `SPACK_ROOT` before
+  sourcing `setup-env.csh` (#18225)
+* Spec syntax now supports `variant=*` syntax for finding any package
+  that has a particular variant (#19381).
+* Spack respects `SPACK_GNUPGHOME` variable for custom GPG directories (#17139)
+* Spack now recognizes Graviton chips
+
+## Major refactors
+
+* Use spawn instead of fork on Python >= 3.8 on macOS (#18205)
+* Use indexes for public build caches (#19101, #19117, #19132, #19141,  #19209)
+* `sbang` is an external package now (https://github.com/spack/sbang, #19582)
+* `archspec` is an external package now (https://github.com/archspec/archspec, #19600)
+
+## Deprecations and Removals
+
+* `spack bootstrap` was deprecated in v0.14.0, and has now been removed.
+* `spack setup` is deprecated as of v0.16.0.
+* What was `spack test` is now called `spack unit-test`. `spack test` is
+  now the smoke testing feature in (2) above.
+
+## Bugfixes
+
+Some of the most notable bugfixes in this release include:
+
+* Better warning messages for deprecated syntax in `packages.yaml` (#18013)
+* `buildcache list --allarch` now works properly (#17827)
+* Many fixes and tests for buildcaches and binary relcoation (#15687,
+  *#17455, #17418, #17455, #15687, #18110)
+
+## Package Improvements
+
+Spack now has 5050 total packages, 720 of which were added since `v0.15`.
+
+* ROCm packages (`hip`, `aomp`, more) added by AMD (#19957, #19832, others)
+* Many improvements for ARM support
+* `llvm-flang`, `flang`, and `f18` removed, as `llvm` has real `flang`
+  support since Flang was merged to LLVM mainline
+* Emerging support for `spack external find` and `spack test` in packages.
+
+## Infrastructure
+
+* Major infrastructure improvements to pipelines on `gitlab.spack.io`
+* Support for testing PRs from forks (#19248) is being enabled for all
+  forks to enable rolling, up-to-date binary builds on `develop`
+
+
+# v0.15.4 (2020-08-12)
+
+This release contains one feature addition:
+
+* Users can set `SPACK_GNUPGHOME` to override Spack's GPG path (#17139)
+
+Several bugfixes for CUDA, binary packaging, and `spack -V`:
+
+* CUDA package's `.libs` method searches for `libcudart` instead of `libcuda` (#18000)
+* Don't set `CUDAHOSTCXX` in environments that contain CUDA (#17826)
+* `buildcache create`: `NoOverwriteException` is a warning, not an error (#17832)
+* Fix `spack buildcache list --allarch` (#17884)
+* `spack -V` works with `releases/latest` tag and shallow clones (#17884)
+
+And fixes for GitHub Actions and tests to ensure that CI passes on the
+release branch (#15687, #17279, #17328, #17377, #17732).
+
+# v0.15.3 (2020-07-28)
+
+This release contains the following bugfixes:
+
+* Fix handling of relative view paths (#17721)
+* Fixes for binary relocation (#17418, #17455)
+* Fix redundant printing of error messages in build environment (#17709)
+
+It also adds a support script for Spack tutorials:
+
+* Add a tutorial setup script to share/spack (#17705, #17722)
+
+# v0.15.2 (2020-07-23)
+
+This minor release includes two new features:
+
+* Spack install verbosity is decreased, and more debug levels are added (#17546)
+* The $spack/share/spack/keys directory contains public keys that may be optionally trusted for public binary mirrors (#17684)
+
+This release also includes several important fixes:
+
+* MPICC and related variables are now cleand in the build environment (#17450)
+* LLVM flang only builds CUDA offload components when +cuda (#17466)
+* CI pipelines no longer upload user environments that can contain secrets to the internet (#17545)
+* CI pipelines add bootstrapped compilers to the compiler config (#17536)
+* `spack buildcache list` does not exit on first failure and lists later mirrors (#17565)
+* Apple's "gcc" executable that is an apple-clang compiler does not generate a gcc compiler config (#17589)
+* Mixed compiler toolchains are merged more naturally across different compiler suffixes (#17590)
+* Cray Shasta platforms detect the OS properly (#17467)
+* Additional more minor fixes.
+
 # v0.15.1 (2020-07-10)
 
 This minor release includes several important fixes:
@@ -558,4 +716,4 @@ version of all the changes since `v0.9.1`.
 - Switched from `nose` to `pytest` for unit tests.
   - Unit tests take 1 minute now instead of 8
 - Massively expanded documentation
-- Docs are now hosted on [spack.readthedocs.io](http://spack.readthedocs.io)
+- Docs are now hosted on [spack.readthedocs.io](https://spack.readthedocs.io)

COPYRIGHT

@@ -28,9 +28,11 @@ text in the license header:
 
 External Packages
 -------------------
-Spack bundles its external dependencies in lib/spack/external.  These
-packages are covered by various permissive licenses.  A summary listing
-follows.  See the license included with each package for full details.
+
+Spack bundles most external dependencies in lib/spack/external. It also
+includes the sbang tool directly in bin/sbang. These packages are covered
+by various permissive licenses. A summary listing follows. See the
+license included with each package for full details.
 
 PackageName: argparse
 PackageHomePage: https://pypi.python.org/pypi/argparse
@@ -76,6 +78,10 @@ PackageName: ruamel.yaml
 PackageHomePage: https://yaml.readthedocs.io/
 PackageLicenseDeclared: MIT
 
+PackageName: sbang
+PackageHomePage: https://github.com/spack/sbang
+PackageLicenseDeclared: Apache-2.0 OR MIT
+
 PackageName: six
 PackageHomePage: https://pypi.python.org/pypi/six
 PackageLicenseDeclared: MIT

LICENSE-MIT

@@ -1,20 +1,21 @@
-Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-Spack Project Developers. See the top-level COPYRIGHT file for details.
+MIT License
 
-Permission is hereby granted, free of charge, to any person obtaining a
-copy of this software and associated documentation files (the "Software"),
-to deal in the Software without restriction, including without limitation
-the rights to use, copy, modify, merge, publish, distribute, sublicense,
-and/or sell copies of the Software, and to permit persons to whom the
-Software is furnished to do so, subject to the following conditions:
+Copyright (c) 2013-2020 LLNS, LLC and other Spack Project Developers.
 
-The above copyright notice and this permission notice shall be included in
-all copies or substantial portions of the Software.
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
-FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
-DEALINGS IN THE SOFTWARE.
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -4,7 +4,6 @@
 [![Linux Tests](https://github.com/spack/spack/workflows/linux%20tests/badge.svg)](https://github.com/spack/spack/actions)
 [![Linux Builds](https://github.com/spack/spack/workflows/linux%20builds/badge.svg)](https://github.com/spack/spack/actions)
 [![macOS Builds (nightly)](https://github.com/spack/spack/workflows/macOS%20builds%20nightly/badge.svg?branch=develop)](https://github.com/spack/spack/actions?query=workflow%3A%22macOS+builds+nightly%22)
-[![Build Status](https://travis-ci.com/spack/spack.svg?branch=develop)](https://travis-ci.com/spack/spack)
 [![codecov](https://codecov.io/gh/spack/spack/branch/develop/graph/badge.svg)](https://codecov.io/gh/spack/spack)
 [![Read the Docs](https://readthedocs.org/projects/spack/badge/?version=latest)](https://spack.readthedocs.io)
 [![Slack](https://spackpm.herokuapp.com/badge.svg)](https://spackpm.herokuapp.com)
@@ -22,7 +21,7 @@ builds of the same package.  With Spack, you can build your software
 *all* the ways you want to.
 
 See the
-[Feature Overview](http://spack.readthedocs.io/en/latest/features.html)
+[Feature Overview](https://spack.readthedocs.io/en/latest/features.html)
 for examples and highlights.
 
 To install spack and your first package, make sure you have Python.
@@ -35,14 +34,14 @@ Then:
 Documentation
 ----------------
 
-[**Full documentation**](http://spack.readthedocs.io/) is available, or
+[**Full documentation**](https://spack.readthedocs.io/) is available, or
 run `spack help` or `spack help --all`.
 
 Tutorial
 ----------------
 
 We maintain a
-[**hands-on tutorial**](http://spack.readthedocs.io/en/latest/tutorial.html).
+[**hands-on tutorial**](https://spack.readthedocs.io/en/latest/tutorial.html).
 It covers basic to advanced usage, packaging, developer features, and large HPC
 deployments.  You can do all of the exercises on your own laptop using a
 Docker container.
@@ -74,15 +73,33 @@ When you send your request, make ``develop`` the destination branch on the
 
 Your PR must pass Spack's unit tests and documentation tests, and must be
 [PEP 8](https://www.python.org/dev/peps/pep-0008/) compliant.  We enforce
-these guidelines with [Travis CI](https://travis-ci.org/spack/spack).  To
-run these tests locally, and for helpful tips on git, see our
-[Contribution Guide](http://spack.readthedocs.io/en/latest/contribution_guide.html).
+these guidelines with our CI process. To run these tests locally, and for 
+helpful tips on git, see our
+[Contribution Guide](https://spack.readthedocs.io/en/latest/contribution_guide.html).
 
-Spack uses a rough approximation of the
-[Git Flow](http://nvie.com/posts/a-successful-git-branching-model/)
-branching model.  The ``develop`` branch contains the latest
-contributions, and ``master`` is always tagged and points to the latest
-stable release.
+Spack's `develop` branch has the latest contributions. Pull requests
+should target `develop`, and users who want the latest package versions,
+features, etc. can use `develop`.
+
+Releases
+--------
+
+For multi-user site deployments or other use cases that need very stable
+software installations, we recommend using Spack's
+[stable releases](https://github.com/spack/spack/releases).
+
+Each Spack release series also has a corresponding branch, e.g.
+`releases/v0.14` has `0.14.x` versions of Spack, and `releases/v0.13` has
+`0.13.x` versions. We backport important bug fixes to these branches but
+we do not advance the package versions or make other changes that would
+change the way Spack concretizes dependencies within a release branch.
+So, you can base your Spack deployment on a release branch and `git pull`
+to get fixes, without the package churn that comes with `develop`.
+
+The latest release is always available with the `releases/latest` tag.
+
+See the [docs on releases](https://spack.readthedocs.io/en/latest/developer_guide.html#releases)
+for more details.
 
 Code of Conduct
 ------------------------
@@ -103,7 +120,7 @@ If you are referencing Spack in a publication, please cite the following paper:
 
  * Todd Gamblin, Matthew P. LeGendre, Michael R. Collette, Gregory L. Lee,
    Adam Moody, Bronis R. de Supinski, and W. Scott Futral.
-   [**The Spack Package Manager: Bringing Order to HPC Software Chaos**](http://www.computer.org/csdl/proceedings/sc/2015/3723/00/2807623.pdf).
+   [**The Spack Package Manager: Bringing Order to HPC Software Chaos**](https://www.computer.org/csdl/proceedings/sc/2015/3723/00/2807623.pdf).
    In *Supercomputing 2015 (SC’15)*, Austin, Texas, November 15-20 2015. LLNL-CONF-669890.
 
 License

bin/sbang

@@ -1,114 +1,103 @@
-#!/bin/bash
+#!/bin/sh
 #
 # Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
+# sbang project developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 #
 # `sbang`: Run scripts with long shebang lines.
 #
-# Many operating systems limit the length of shebang lines, making it
-# hard to use interpreters that are deep in the directory hierarchy.
-# `sbang` can run such scripts, either as a shebang interpreter, or
-# directly on the command line.
+# Many operating systems limit the length and number of possible
+# arguments in shebang lines, making it hard to use interpreters that are
+# deep in the directory hierarchy or require special arguments.
 #
-# Usage
-# -----------------------------
-# Suppose you have a script, long-shebang.sh, like this:
+# To use, put the long shebang on the second line of your script, and
+# make sbang the interpreter, like this:
 #
-#     1    #!/very/long/path/to/some/interpreter
-#     2
-#     3    echo "success!"
+#     #!/bin/sh /path/to/sbang
+#     #!/long/path/to/real/interpreter with arguments
 #
-# Invoking this script will result in an error on some OS's.  On
-# Linux, you get this:
+# `sbang` will run the real interpreter with the script as its argument.
 #
-#     $ ./long-shebang.sh
-#     -bash: ./long: /very/long/path/to/some/interp: bad interpreter:
-#            No such file or directory
-#
-# On Mac OS X, the system simply assumes the interpreter is the shell
-# and tries to run with it, which is likely not what you want.
-#
-#
-# `sbang` on the command line
-# -----------------------------
-# You can use `sbang` in two ways.  The first is to use it directly,
-# from the command line, like this:
-#
-#     $ sbang ./long-shebang.sh
-#     success!
-#
-#
-# `sbang` as the interpreter
-# -----------------------------
-# You can also use `sbang` *as* the interpreter for your script. Put
-# `#!/bin/bash /path/to/sbang` on line 1, and move the original
-# shebang to line 2 of the script:
-#
-#     1    #!/bin/bash /path/to/sbang
-#     2    #!/long/path/to/real/interpreter with arguments
-#     3
-#     4    echo "success!"
-#
-#     $ ./long-shebang.sh
-#     success!
-#
-# On Linux, you could shorten line 1 to `#!/path/to/sbang`, but other
-# operating systems like Mac OS X require the interpreter to be a
-# binary, so it's best to use `sbang` as a `bash` argument.
-# Obviously, for this to work, `sbang` needs to have a short enough
-# path that *it* will run without hitting OS limits.
-#
-# For Lua, scripts the second line can't start with #!, as # is not
-# the comment character in lua (even though lua ignores #! on the
-# *first* line of a script).  So, instrument a lua script like this,
-# using -- instead of # on the second line:
-#
-#     1    #!/bin/bash /path/to/sbang
-#     2    --!/long/path/to/lua with arguments
-#     3
-#     4    print "success!"
-#
-# How it works
-# -----------------------------
-# `sbang` is a very simple bash script. It looks at the first two
-# lines of a script argument and runs the last line starting with
-# `#!`, with the script as an argument. It also forwards arguments.
+# See https://github.com/spack/sbang for more details.
 #
 
+# Generic error handling
+die() {
+    echo "$@" 1>&2;
+    exit 1
+}
+
+# set SBANG_DEBUG to make the script print what would normally be executed.
+exec="exec"
+if [ -n "${SBANG_DEBUG}" ]; then
+    exec="echo "
+fi
+
 # First argument is the script we want to actually run.
 script="$1"
 
+# ensure that the script actually exists
+if [ -z "$script" ]; then
+    die "error: sbang requires exactly one argument"
+elif [ ! -f "$script" ]; then
+    die "$script: no such file or directory"
+fi
+
 # Search the first two lines of script for interpreters.
 lines=0
-while read line && ((lines < 2)) ; do
-    if [[ "$line" = '#!'* ]]; then
-        interpreter="${line#\#!}"
-    elif [[ "$line" = '//!'*node* ]]; then
-        interpreter="${line#//!}"
-    elif [[ "$line" = '--!'*lua* ]]; then
-        interpreter="${line#--!}"
+while read -r line && [ $lines -ne 2 ]; do
+    if [ "${line#\#!}" != "$line" ]; then
+        shebang_line="${line#\#!}"
+    elif [ "${line#//!}" != "$line" ]; then      # // comments
+        shebang_line="${line#//!}"
+    elif [ "${line#--!}" != "$line" ]; then      # -- lua comments
+        shebang_line="${line#--!}"
+    elif [ "${line#<?php\ }" != "$line" ]; then  # php comments
+        shebang_line="${line#<?php\ \#!}"
+        shebang_line="${shebang_line%\ ?>}"
     fi
     lines=$((lines+1))
 done < "$script"
-# this is ineeded for scripts with sbang parameter
-# like ones in intltool
-# #!/<spack-long-path>/perl -w
-# this is the interpreter line with all the parameters as a vector
-interpreter_v=(${interpreter})
-# this is the single interpreter path 
-interpreter_f="${interpreter_v[0]}"
 
-# Invoke any interpreter found, or raise an error if none was found.
-if [[ -n "$interpreter_f" ]]; then
-    if [[ "${interpreter_f##*/}" = "perl"* ]]; then
-        exec $interpreter -x "$@"
-    else
-        exec $interpreter "$@"
-    fi
-else
-    echo "error: sbang found no interpreter in $script"
-    exit 1
+# error if we did not find any interpreter
+if [ -z "$shebang_line"  ]; then
+    die "error: sbang found no interpreter in $script"
+fi
+
+# parse out the interpreter and first argument
+IFS=' ' read -r interpreter arg1 rest <<EOF
+$shebang_line
+EOF
+
+# Determine if the interpreter is a particular program, accounting for the
+# '#!/usr/bin/env PROGRAM' convention. So:
+#
+#     interpreter_is perl
+#
+# will be true for '#!/usr/bin/perl' and '#!/usr/bin/env perl'
+interpreter_is() {
+    if [ "${interpreter##*/}" = "$1" ]; then
+        return 0
+    elif [ "$interpreter" = "/usr/bin/env" ] && [ "$arg1" = "$1" ]; then
+        return 0
+    else
+        return 1
+    fi
+}
+
+if interpreter_is "sbang"; then
+    die "error: refusing to re-execute sbang to avoid infinite loop."
+fi
+
+# Finally invoke the real shebang line
+# ruby and perl need -x to ignore the first line of input (the sbang line)
+#
+if interpreter_is perl || interpreter_is ruby; then
+    # shellcheck disable=SC2086
+    $exec $shebang_line -x "$@"
+else
+    # shellcheck disable=SC2086
+    $exec $shebang_line "$@"
 fi

bin/spack

@@ -1,7 +1,7 @@
 #!/bin/sh
 # -*- python -*-
 #
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -10,9 +10,12 @@
 # Following line is a shell no-op, and starts a multi-line Python comment.
 # See https://stackoverflow.com/a/47886254
 """:"
-# prefer python3, then python, then python2
-for cmd in python3 python python2; do
-   command -v > /dev/null $cmd && exec $cmd $0 "$@"
+# prefer SPACK_PYTHON environment variable, python3, python, then python2
+for cmd in "${SPACK_PYTHON:-}" python3 python python2; do
+    if command -v > /dev/null "$cmd"; then
+        export SPACK_PYTHON="$(command -v "$cmd")"
+        exec "${SPACK_PYTHON}" "$0" "$@"
+    fi
 done
 
 echo "==> Error: spack could not find a python interpreter!" >&2
@@ -42,6 +45,8 @@ sys.path.insert(0, spack_lib_path)
 # Add external libs
 spack_external_libs = os.path.join(spack_lib_path, "external")
 
+if sys.version_info[:2] <= (2, 7):
+    sys.path.insert(0, os.path.join(spack_external_libs, 'py2'))
 if sys.version_info[:2] == (2, 6):
     sys.path.insert(0, os.path.join(spack_external_libs, 'py26'))
 
@@ -59,6 +64,8 @@ if 'ruamel.yaml' in sys.modules:
 if 'ruamel' in sys.modules:
     del sys.modules['ruamel']
 
-# Once we've set up the system path, run the spack main method
 import spack.main  # noqa
-sys.exit(spack.main.main())
+
+# Once we've set up the system path, run the spack main method
+if __name__ == "__main__":
+    sys.exit(spack.main.main())

bin/spack-python

@@ -1,6 +1,6 @@
 #!/bin/sh
 #
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)

etc/spack/defaults/config.yaml

@@ -16,7 +16,17 @@
 config:
   # This is the path to the root of the Spack install tree.
   # You can use $spack here to refer to the root of the spack instance.
-  install_tree: $spack/opt/spack
+  install_tree:
+    root: $spack/opt/spack
+    projections:
+      all: "${ARCHITECTURE}/${COMPILERNAME}-${COMPILERVER}/${PACKAGE}-${VERSION}-${HASH}"
+    # install_tree can include an optional padded length (int or boolean)
+    # default is False (do not pad)
+    # if padded_length is True, Spack will pad as close to the system max path
+    # length as possible
+    # if padded_length is an integer, Spack will pad to that many characters,
+    # assuming it is higher than the length of the install_tree root.
+    # padded_length: 128
 
 
   # Locations where templates should be found
@@ -24,10 +34,6 @@ config:
     - $spack/share/spack/templates
 
 
-  # Default directory layout
-  install_path_scheme: "${ARCHITECTURE}/${COMPILERNAME}-${COMPILERVER}/${PACKAGE}-${VERSION}-${HASH}"
-
-
   # Locations where different types of modules should be installed.
   module_roots:
     tcl:    $spack/share/spack/modules
@@ -64,6 +70,10 @@ config:
     - ~/.spack/stage
   # - $spack/var/spack/stage
 
+  # Directory in which to run tests and store test results.
+  # Tests will be stored in directories named by date/time and package
+  # name/hash.
+  test_stage: ~/.spack/test
 
   # Cache directory for already downloaded source tarballs and archived
   # repositories. This can be purged with `spack clean --downloads`.
@@ -97,7 +107,7 @@ config:
   # If set to true, Spack will attempt to build any compiler on the spec
   # that is not already available. If set to False, Spack will only use
   # compilers already configured in compilers.yaml
-  install_missing_compilers: False
+  install_missing_compilers: false
 
 
   # If set to true, Spack will always check checksums after downloading
@@ -105,6 +115,11 @@ config:
   checksum: true
 
 
+  # If set to true, Spack will fetch deprecated versions without warning.
+  # If false, Spack will raise an error when trying to install a deprecated version.
+  deprecated: false
+
+
   # If set to true, `spack install` and friends will NOT clean
   # potentially harmful variables from the build environment. Use wisely.
   dirty: false
@@ -139,6 +154,20 @@ config:
   ccache: false
 
 
+  # The concretization algorithm to use in Spack. Options are:
+  #
+  #   'original': Spack's original greedy, fixed-point concretizer. This
+  #       algorithm can make decisions too early and will not backtrack
+  #       sufficiently for many specs.
+  #
+  #   'clingo': Uses a logic solver under the hood to solve DAGs with full
+  #       backtracking and optimization for user preferences.
+  #
+  # 'clingo' currently requires the clingo ASP solver to be installed and
+  # built with python bindings. 'original' is built in.
+  concretizer: original
+
+
   # How long to wait to lock the Spack installation database. This lock is used
   # when Spack needs to manage its own package metadata and all operations are
   # expected to complete within the default time limit. The timeout should
@@ -153,11 +182,13 @@ config:
   # never succeed.
   package_lock_timeout: null
 
+
   # Control whether Spack embeds RPATH or RUNPATH attributes in ELF binaries.
   # Has no effect on macOS. DO NOT MIX these within the same install tree.
   # See the Spack documentation for details.
   shared_linking: 'rpath'
 
+
   # Set to 'false' to allow installation on filesystems that doesn't allow setgid bit
   # manipulation by unprivileged user (e.g. AFS)
   allow_sgid: true

etc/spack/defaults/darwin/packages.yaml

@@ -21,11 +21,23 @@ packages:
     - gcc
     - intel
     providers:
-      elf: [libelf]
-      unwind: [apple-libunwind]
+      elf:
+      - libelf
+      unwind:
+      - apple-libunwind
+      uuid:
+      - apple-libuuid
   apple-libunwind:
-    paths:
+    buildable: false
+    externals:
     # Apple bundles libunwind version 35.3 with macOS 10.9 and later,
     # although the version number used here isn't critical
-      apple-libunwind@35.3: /usr
-    buildable: False
+    - spec: apple-libunwind@35.3
+      prefix: /usr
+  apple-libuuid:
+    buildable: false
+    externals:
+    # Apple bundles libuuid in libsystem_c version 1353.100.2,
+    # although the version number used here isn't critical
+    - spec: apple-libuuid@1353.100.2
+      prefix: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk

etc/spack/defaults/packages.yaml

@@ -15,38 +15,41 @@
 # -------------------------------------------------------------------------
 packages:
   all:
-    compiler: [gcc, intel, pgi, clang, xl, nag, fj]
+    compiler: [gcc, intel, pgi, clang, xl, nag, fj, aocc]
     providers:
       D: [ldc]
       awk: [gawk]
-      blas: [openblas]
+      blas: [openblas, amdblis]
       daal: [intel-daal]
       elf: [elfutils]
-      fftw-api: [fftw]
-      gl: [mesa+opengl, opengl]
-      glx: [mesa+glx, opengl]
+      fftw-api: [fftw, amdfftw]
+      gl: [mesa+opengl, mesa18, opengl]
+      glx: [mesa+glx, mesa18+glx, opengl]
       glu: [mesa-glu, openglu]
       golang: [gcc]
       iconv: [libiconv]
       ipp: [intel-ipp]
       java: [openjdk, jdk, ibm-java]
       jpeg: [libjpeg-turbo, libjpeg]
-      lapack: [openblas]
+      lapack: [openblas, amdlibflame]
       mariadb-client: [mariadb-c-client, mariadb]
       mkl: [intel-mkl]
       mpe: [mpe2]
       mpi: [openmpi, mpich]
       mysql-client: [mysql, mariadb-c-client]
       opencl: [pocl]
+      osmesa: [mesa+osmesa, mesa18+osmesa]
       pil: [py-pillow]
       pkgconfig: [pkgconf, pkg-config]
       rpc: [libtirpc]
-      scalapack: [netlib-scalapack]
+      scalapack: [netlib-scalapack, amdscalapack]
       sycl: [hipsycl]
       szip: [libszip, libaec]
       tbb: [intel-tbb]
       unwind: [libunwind]
-      sycl: [hipsycl]
+      yacc: [bison, byacc]
+      flame: [libflame, amdlibflame]
+      uuid: [util-linux-uuid, libuuid]
     permissions:
       read: world
       write: user

lib/spack/docs/_gh_pages_redirect/index.html

@@ -1,10 +1,10 @@
 <html>
   <head>
-    <meta http-equiv="refresh" content="0; url=http://spack.readthedocs.io/" />
+    <meta http-equiv="refresh" content="0; url=https://spack.readthedocs.io/" />
   </head>
   <body>
     <p>
-      This page has moved to <a href="http://spack.readthedocs.io/">http://spack.readthedocs.io/</a>
+      This page has moved to <a href="https://spack.readthedocs.io/">https://spack.readthedocs.io/</a>
     </p>
   </body>
 </html>

lib/spack/docs/basic_usage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -31,7 +31,7 @@ colorized output.
 
 .. code-block:: console
 
-    $ spack --color always | less -R 
+    $ spack --color always | less -R
 
 --------------------------
 Listing available packages
@@ -132,32 +132,27 @@ If ``mpileaks`` depends on other packages, Spack will install the
 dependencies first.  It then fetches the ``mpileaks`` tarball, expands
 it, verifies that it was downloaded without errors, builds it, and
 installs it in its own directory under ``$SPACK_ROOT/opt``. You'll see
-a number of messages from spack, a lot of build output, and a message
-that the packages is installed:
+a number of messages from Spack, a lot of build output, and a message
+that the package is installed.
 
 .. code-block:: console
 
    $ spack install mpileaks
-   ==> Installing mpileaks
-   ==> mpich is already installed in ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpich@3.0.4.
-   ==> callpath is already installed in ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/callpath@1.0.2-5dce4318.
-   ==> adept-utils is already installed in ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/adept-utils@1.0-5adef8da.
-   ==> Trying to fetch from https://github.com/hpc/mpileaks/releases/download/v1.0/mpileaks-1.0.tar.gz
-   ######################################################################## 100.0%
-   ==> Staging archive: ~/spack/var/spack/stage/mpileaks@1.0%gcc@4.4.7 arch=linux-debian7-x86_64-59f6ad23/mpileaks-1.0.tar.gz
-   ==> Created stage in ~/spack/var/spack/stage/mpileaks@1.0%gcc@4.4.7 arch=linux-debian7-x86_64-59f6ad23.
-   ==> No patches needed for mpileaks.
-   ==> Building mpileaks.
-
-   ... build output ...
-
-   ==> Successfully installed mpileaks.
-     Fetch: 2.16s.  Build: 9.82s.  Total: 11.98s.
-   [+] ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpileaks@1.0-59f6ad23
+   ... dependency build output ...
+   ==> Installing mpileaks-1.0-ph7pbnhl334wuhogmugriohcwempqry2
+   ==> No binary for mpileaks-1.0-ph7pbnhl334wuhogmugriohcwempqry2 found: installing from source
+   ==> mpileaks: Executing phase: 'autoreconf'
+   ==> mpileaks: Executing phase: 'configure'
+   ==> mpileaks: Executing phase: 'build'
+   ==> mpileaks: Executing phase: 'install'
+   [+] ~/spack/opt/linux-rhel7-broadwell/gcc-8.1.0/mpileaks-1.0-ph7pbnhl334wuhogmugriohcwempqry2
 
 The last line, with the ``[+]``, indicates where the package is
 installed.
 
+Add the Spack debug option (one or more times) -- ``spack -d install
+mpileaks`` -- to get additional (and even more verbose) output.
+
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Building a specific version
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -284,6 +279,102 @@ and removed everything that is not either:
 You can check :ref:`cmd-spack-find-metadata` to see how to query for explicitly installed packages
 or :ref:`dependency-types` for a more thorough treatment of dependency types.
 
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Marking packages explicit or implicit
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+By default, Spack will mark packages a user installs as explicitly installed,
+while all of its dependencies will be marked as implicitly installed. Packages
+can be marked manually as explicitly or implicitly installed by using
+``spack mark``. This can be used in combination with ``spack gc`` to clean up
+packages that are no longer required.
+
+.. code-block:: console
+
+  $ spack install m4
+  ==> 29005: Installing libsigsegv
+  [...]
+  ==> 29005: Installing m4
+  [...]
+
+  $ spack install m4 ^libsigsegv@2.11
+  ==> 39798: Installing libsigsegv
+  [...]
+  ==> 39798: Installing m4
+  [...]
+
+  $ spack find -d
+  ==> 4 installed packages
+  -- linux-fedora32-haswell / gcc@10.1.1 --------------------------
+  libsigsegv@2.11
+
+  libsigsegv@2.12
+
+  m4@1.4.18
+      libsigsegv@2.12
+
+  m4@1.4.18
+      libsigsegv@2.11
+
+  $ spack gc
+  ==> There are no unused specs. Spack's store is clean.
+
+  $ spack mark -i m4 ^libsigsegv@2.11
+  ==> m4@1.4.18 : marking the package implicit
+
+  $ spack gc
+  ==> The following packages will be uninstalled:
+
+      -- linux-fedora32-haswell / gcc@10.1.1 --------------------------
+      5fj7p2o libsigsegv@2.11  c6ensc6 m4@1.4.18
+
+  ==> Do you want to proceed? [y/N]
+
+In the example above, we ended up with two versions of ``m4`` since they depend
+on different versions of ``libsigsegv``. ``spack gc`` will not remove any of
+the packages since both versions of ``m4`` have been installed explicitly
+and both versions of ``libsigsegv`` are required by the ``m4`` packages.
+
+``spack mark`` can also be used to implement upgrade workflows. The following
+example demonstrates how the ``spack mark`` and ``spack gc`` can be used to
+only keep the current version of a package installed.
+
+When updating Spack via ``git pull``, new versions for either ``libsigsegv``
+or ``m4`` might be introduced. This will cause Spack to install duplicates.
+Since we only want to keep one version, we mark everything as implicitly
+installed before updating Spack. If there is no new version for either of the
+packages, ``spack install`` will simply mark them as explicitly installed and
+``spack gc`` will not remove them.
+
+.. code-block:: console
+
+  $ spack install m4
+  ==> 62843: Installing libsigsegv
+  [...]
+  ==> 62843: Installing m4
+  [...]
+
+  $ spack mark -i -a
+  ==> m4@1.4.18 : marking the package implicit
+
+  $ git pull
+  [...]
+
+  $ spack install m4
+  [...]
+  ==> m4@1.4.18 : marking the package explicit
+  [...]
+
+  $ spack gc
+  ==> There are no unused specs. Spack's store is clean.
+
+When using this workflow for installations that contain more packages, care
+has to be taken to either only mark selected packages or issue ``spack install``
+for all packages that should be kept.
+
+You can check :ref:`cmd-spack-find-metadata` to see how to query for explicitly
+or implicitly installed packages.
+
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 Non-Downloadable Tarballs
 ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -329,85 +420,6 @@ the tarballs in question to it (see :ref:`mirrors`):
 
        $ spack install galahad
 
------------------------------
-Deprecating insecure packages
------------------------------
-
-``spack deprecate`` allows for the removal of insecure packages with
-minimal impact to their dependents.
-
-.. warning::
-
-  The ``spack deprecate`` command is designed for use only in
-  extraordinary circumstances. This is a VERY big hammer to be used
-  with care.
-
-The ``spack deprecate`` command will remove one package and replace it
-with another by replacing the deprecated package's prefix with a link
-to the deprecator package's prefix.
-
-.. warning::
-
-  The ``spack deprecate`` command makes no promises about binary
-  compatibility. It is up to the user to ensure the deprecator is
-  suitable for the deprecated package.
-
-Spack tracks concrete deprecated specs and ensures that no future packages
-concretize to a deprecated spec.
-
-The first spec given to the ``spack deprecate`` command is the package
-to deprecate. It is an abstract spec that must describe a single
-installed package. The second spec argument is the deprecator
-spec. By default it must be an abstract spec that describes a single
-installed package, but with the ``-i/--install-deprecator`` it can be
-any abstract spec that Spack will install and then use as the
-deprecator. The ``-I/--no-install-deprecator`` option will ensure
-the default behavior.
-
-By default, ``spack deprecate`` will deprecate all dependencies of the
-deprecated spec, replacing each by the dependency of the same name in
-the deprecator spec. The ``-d/--dependencies`` option will ensure the
-default, while the ``-D/--no-dependencies`` option will deprecate only
-the root of the deprecate spec in favor of the root of the deprecator
-spec.
-
-``spack deprecate`` can use symbolic links or hard links. The default
-behavior is symbolic links, but the ``-l/--link-type`` flag can take
-options ``hard`` or ``soft``.
-
------------------------
-Verifying installations
------------------------
-
-The ``spack verify`` command can be used to verify the validity of
-Spack-installed packages any time after installation.
-
-At installation time, Spack creates a manifest of every file in the
-installation prefix. For links, Spack tracks the mode, ownership, and
-destination. For directories, Spack tracks the mode, and
-ownership. For files, Spack tracks the mode, ownership, modification
-time, hash, and size. The Spack verify command will check, for every
-file in each package, whether any of those attributes have changed. It
-will also check for newly added files or deleted files from the
-installation prefix. Spack can either check all installed packages
-using the `-a,--all` or accept specs listed on the command line to
-verify.
-
-The ``spack verify`` command can also verify for individual files that
-they haven't been altered since installation time. If the given file
-is not in a Spack installation prefix, Spack will report that it is
-not owned by any package. To check individual files instead of specs,
-use the ``-f,--files`` option.
-
-Spack installation manifests are part of the tarball signed by Spack
-for binary package distribution. When installed from a binary package,
-Spack uses the packaged installation manifest instead of creating one
-at install time.
-
-The ``spack verify`` command also accepts the ``-l,--local`` option to
-check only local packages (as opposed to those used transparently from
-``upstream`` spack instances) and the ``-j,--json`` option to output
-machine-readable json data for any errors.
 
 -------------------------
 Seeing installed packages
@@ -676,6 +688,95 @@ structured the way you want:
       "hash": "zvaa4lhlhilypw5quj3akyd3apbq5gap"
     }
 
+
+------------------------
+Using installed packages
+------------------------
+
+There are several different ways to use Spack packages once you have
+installed them. As you've seen, spack packages are installed into long
+paths with hashes, and you need a way to get them into your path. The
+easiest way is to use :ref:`spack load <cmd-spack-load>`, which is
+described in the next section.
+
+Some more advanced ways to use Spack packages include:
+
+* :ref:`environments <environments>`, which you can use to bundle a
+  number of related packages to "activate" all at once, and
+* :ref:`environment modules <modules>`, which are commonly used on
+  supercomputing clusters. Spack generates module files for every
+  installation automatically, and you can customize how this is done.
+
+.. _cmd-spack-load:
+
+^^^^^^^^^^^^^^^^^^^^^^^
+``spack load / unload``
+^^^^^^^^^^^^^^^^^^^^^^^
+
+If you have :ref:`shell support <shell-support>` enabled you can use the
+``spack load`` command to quickly get a package on your ``PATH``.
+
+For example this will add the ``mpich`` package built with ``gcc`` to
+your path:
+
+.. code-block:: console
+
+   $ spack install mpich %gcc@4.4.7
+
+   # ... wait for install ...
+
+   $ spack load mpich %gcc@4.4.7
+   $ which mpicc
+   ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpich@3.0.4/bin/mpicc
+
+These commands will add appropriate directories to your ``PATH``,
+``MANPATH``, ``CPATH``, and ``LD_LIBRARY_PATH`` according to the
+:ref:`prefix inspections <customize-env-modifications>` defined in your
+modules configuration.  When you no longer want to use a package, you
+can type unload or unuse similarly:
+
+.. code-block:: console
+
+   $ spack unload mpich %gcc@4.4.7
+
+
+"""""""""""""""
+Ambiguous specs
+"""""""""""""""
+
+If a spec used with load/unload or is ambiguous (i.e. more than one
+installed package matches it), then Spack will warn you:
+
+.. code-block:: console
+
+   $ spack load libelf
+   ==> Error: libelf matches multiple packages.
+   Matching packages:
+     qmm4kso libelf@0.8.13%gcc@4.4.7 arch=linux-debian7-x86_64
+     cd2u6jt libelf@0.8.13%intel@15.0.0 arch=linux-debian7-x86_64
+   Use a more specific spec
+
+You can either type the ``spack load`` command again with a fully
+qualified argument, or you can add just enough extra constraints to
+identify one package.  For example, above, the key differentiator is
+that one ``libelf`` is built with the Intel compiler, while the other
+used ``gcc``.  You could therefore just type:
+
+.. code-block:: console
+
+   $ spack load libelf %intel
+
+To identify just the one built with the Intel compiler. If you want to be
+*very* specific, you can load it by its hash. For example, to load the
+first ``libelf`` above, you would run:
+
+.. code-block:: console
+
+   $ spack load /qmm4kso
+
+We'll learn more about Spack's spec syntax in the next section.
+
+
 .. _sec-specs:
 
 --------------------
@@ -695,11 +796,11 @@ Here is an example of a much longer spec than we've seen thus far:
 
 .. code-block:: none
 
-   mpileaks @1.2:1.4 %gcc@4.7.5 +debug -qt arch=bgq_os ^callpath @1.1 %gcc@4.7.2
+   mpileaks @1.2:1.4 %gcc@4.7.5 +debug -qt target=x86_64 ^callpath @1.1 %gcc@4.7.2
 
 If provided to ``spack install``, this will install the ``mpileaks``
 library at some version between ``1.2`` and ``1.4`` (inclusive),
-built using ``gcc`` at version 4.7.5 for the Blue Gene/Q architecture,
+built using ``gcc`` at version 4.7.5 for a generic ``x86_64`` architecture,
 with debug options enabled, and without Qt support.  Additionally, it
 says to link it with the ``callpath`` library (which it depends on),
 and to build callpath with ``gcc`` 4.7.2.  Most specs will not be as
@@ -1234,6 +1335,88 @@ add a version specifier to the spec:
 Notice that the package versions that provide insufficient MPI
 versions are now filtered out.
 
+
+-----------------------------
+Deprecating insecure packages
+-----------------------------
+
+``spack deprecate`` allows for the removal of insecure packages with
+minimal impact to their dependents.
+
+.. warning::
+
+  The ``spack deprecate`` command is designed for use only in
+  extraordinary circumstances. This is a VERY big hammer to be used
+  with care.
+
+The ``spack deprecate`` command will remove one package and replace it
+with another by replacing the deprecated package's prefix with a link
+to the deprecator package's prefix.
+
+.. warning::
+
+  The ``spack deprecate`` command makes no promises about binary
+  compatibility. It is up to the user to ensure the deprecator is
+  suitable for the deprecated package.
+
+Spack tracks concrete deprecated specs and ensures that no future packages
+concretize to a deprecated spec.
+
+The first spec given to the ``spack deprecate`` command is the package
+to deprecate. It is an abstract spec that must describe a single
+installed package. The second spec argument is the deprecator
+spec. By default it must be an abstract spec that describes a single
+installed package, but with the ``-i/--install-deprecator`` it can be
+any abstract spec that Spack will install and then use as the
+deprecator. The ``-I/--no-install-deprecator`` option will ensure
+the default behavior.
+
+By default, ``spack deprecate`` will deprecate all dependencies of the
+deprecated spec, replacing each by the dependency of the same name in
+the deprecator spec. The ``-d/--dependencies`` option will ensure the
+default, while the ``-D/--no-dependencies`` option will deprecate only
+the root of the deprecate spec in favor of the root of the deprecator
+spec.
+
+``spack deprecate`` can use symbolic links or hard links. The default
+behavior is symbolic links, but the ``-l/--link-type`` flag can take
+options ``hard`` or ``soft``.
+
+-----------------------
+Verifying installations
+-----------------------
+
+The ``spack verify`` command can be used to verify the validity of
+Spack-installed packages any time after installation.
+
+At installation time, Spack creates a manifest of every file in the
+installation prefix. For links, Spack tracks the mode, ownership, and
+destination. For directories, Spack tracks the mode, and
+ownership. For files, Spack tracks the mode, ownership, modification
+time, hash, and size. The Spack verify command will check, for every
+file in each package, whether any of those attributes have changed. It
+will also check for newly added files or deleted files from the
+installation prefix. Spack can either check all installed packages
+using the `-a,--all` or accept specs listed on the command line to
+verify.
+
+The ``spack verify`` command can also verify for individual files that
+they haven't been altered since installation time. If the given file
+is not in a Spack installation prefix, Spack will report that it is
+not owned by any package. To check individual files instead of specs,
+use the ``-f,--files`` option.
+
+Spack installation manifests are part of the tarball signed by Spack
+for binary package distribution. When installed from a binary package,
+Spack uses the packaged installation manifest instead of creating one
+at install time.
+
+The ``spack verify`` command also accepts the ``-l,--local`` option to
+check only local packages (as opposed to those used transparently from
+``upstream`` spack instances) and the ``-j,--json`` option to output
+machine-readable json data for any errors.
+
+
 .. _extensions:
 
 ---------------------------

lib/spack/docs/binary_caches.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_settings.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -57,10 +57,13 @@ directory. Here's an example of an external configuration:
 
    packages:
      openmpi:
-       paths:
-         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64: /opt/openmpi-1.4.3
-         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug: /opt/openmpi-1.4.3-debug
-         openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64: /opt/openmpi-1.6.5-intel
+       externals:
+       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64"
+         prefix: /opt/openmpi-1.4.3
+       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug"
+         prefix: /opt/openmpi-1.4.3-debug
+       - spec: "openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64"
+         prefix: /opt/openmpi-1.6.5-intel
 
 This example lists three installations of OpenMPI, one built with GCC,
 one built with GCC and debug information, and another built with Intel.
@@ -76,13 +79,15 @@ of the installation prefixes.  The following example says that module
 .. code-block:: yaml
 
    cmake:
-     modules:
-       cmake@3.7.2: CMake/3.7.2
+     externals:
+     - spec: cmake@3.7.2
+       modules:
+       - CMake/3.7.2
 
-Each ``packages.yaml`` begins with a ``packages:`` token, followed
-by a list of package names.  To specify externals, add a ``paths`` or ``modules``
-token under the package name, which lists externals in a
-``spec: /path`` or ``spec: module-name`` format.  Each spec should be as
+Each ``packages.yaml`` begins with a ``packages:`` attribute, followed
+by a list of package names.  To specify externals, add an ``externals:``
+attribute under the package name, which lists externals.
+Each external should specify a ``spec:`` string that should be as
 well-defined as reasonably possible.  If a
 package lacks a spec component, such as missing a compiler or
 package version, then Spack will guess the missing component based
@@ -106,10 +111,13 @@ be:
 
    packages:
      openmpi:
-       paths:
-         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64: /opt/openmpi-1.4.3
-         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug: /opt/openmpi-1.4.3-debug
-         openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64: /opt/openmpi-1.6.5-intel
+       externals:
+       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64"
+         prefix: /opt/openmpi-1.4.3
+       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug"
+         prefix: /opt/openmpi-1.4.3-debug
+       - spec: "openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64"
+         prefix: /opt/openmpi-1.6.5-intel
        buildable: False
 
 The addition of the ``buildable`` flag tells Spack that it should never build
@@ -137,10 +145,13 @@ but more conveniently:
      mpi:
        buildable: False
      openmpi:
-       paths:
-         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64: /opt/openmpi-1.4.3
-         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug: /opt/openmpi-1.4.3-debug
-         openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64: /opt/openmpi-1.6.5-intel
+       externals:
+       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64"
+         prefix: /opt/openmpi-1.4.3
+       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug"
+         prefix: /opt/openmpi-1.4.3-debug
+       - spec: "openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64"
+         prefix: /opt/openmpi-1.6.5-intel
 
 Implementations can also be listed immediately under the virtual they provide:
 
@@ -172,8 +183,9 @@ After running this command your ``packages.yaml`` may include new entries:
 
    packages:
      cmake:
-       paths:
-         cmake@3.17.2: /usr
+       externals:
+       - spec: cmake@3.17.2
+         prefix: /usr
 
 Generally this is useful for detecting a small set of commonly-used packages;
 for now this is generally limited to finding build-only dependencies.

lib/spack/docs/build_systems.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -29,6 +29,7 @@ on these ideas for each distinct build system that Spack supports:
    :maxdepth: 1
    :caption: Make-incompatible
 
+   build_systems/mavenpackage
    build_systems/sconspackage
    build_systems/wafpackage
 
@@ -59,6 +60,7 @@ on these ideas for each distinct build system that Spack supports:
    build_systems/bundlepackage
    build_systems/cudapackage
    build_systems/intelpackage
+   build_systems/rocmpackage
    build_systems/custompackage
 
 For reference, the :py:mod:`Build System API docs <spack.build_systems>`

lib/spack/docs/build_systems/autotoolspackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/bundlepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/cmakepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/cudapackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -9,35 +9,120 @@
 CudaPackage
 -----------
 
-Different from other packages, ``CudaPackage`` does not represent a build
-system. Instead its goal is to simplify and unify usage of ``CUDA`` in other
-packages.
+Different from other packages, ``CudaPackage`` does not represent a build system.
+Instead its goal is to simplify and unify usage of ``CUDA`` in other packages by providing a ` mixin-class <https://en.wikipedia.org/wiki/Mixin>`__.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Provided variants and dependencies
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+You can find source for the package at
+`<https://github.com/spack/spack/blob/develop/lib/spack/spack/build_systems/cuda.py>`__.
 
-``CudaPackage`` provides ``cuda`` variant (default to ``off``) to enable/disable
-``CUDA``, and ``cuda_arch`` variant to optionally specify the architecture.
-It also declares dependencies on the ``CUDA`` package ``depends_on('cuda@...')``
-based on the architecture as well as specifies conflicts for certain compiler versions.
+^^^^^^^^
+Variants
+^^^^^^^^
+
+This package provides the following variants:
+
+* **cuda**
+
+  This variant is used to enable/disable building with ``CUDA``. The default
+  is disabled (or ``False``).
+
+* **cuda_arch**
+
+  This variant supports the optional specification of the architecture.
+  Valid values are maintained in the ``cuda_arch_values`` property and
+  are the numeric character equivalent of the compute capability version
+  (e.g., '10' for version 1.0). Each provided value affects associated
+  ``CUDA`` dependencies and compiler conflicts.
+
+  GPUs and their compute capability versions are listed at
+  https://developer.nvidia.com/cuda-gpus .
+
+^^^^^^^^^
+Conflicts
+^^^^^^^^^
+
+Conflicts are used to prevent builds with known bugs or issues. While
+base ``CUDA`` conflicts have been included with this package, you may
+want to add more for your software.
+
+For example, if your package requires ``cuda_arch`` to be specified when
+``cuda`` is enabled, you can add the following conflict to your package
+to terminate such build attempts with a suitable message:
+
+.. code-block:: python
+
+    conflicts('cuda_arch=none', when='+cuda',
+              msg='CUDA architecture is required')
+
+Similarly, if your software does not support all versions of the property,
+you could add ``conflicts`` to your package for those versions.  For example,
+suppose your software does not work with CUDA compute capability versions
+prior to SM 5.0 (``50``).  You can add the following code to display a
+custom message should a user attempt such a build:
+
+.. code-block:: python
+
+    unsupported_cuda_archs = [
+        '10', '11', '12', '13',
+        '20', '21',
+        '30', '32', '35', '37'
+    ]
+    for value in unsupported_cuda_archs:
+        conflicts('cuda_arch={0}'.format(value), when='+cuda',
+                  msg='CUDA architecture {0} is not supported'.format(value))
+
+^^^^^^^
+Methods
+^^^^^^^
+
+This package provides one custom helper method, which is used to build
+standard CUDA compiler flags.
+
+**cuda_flags**
+
+    This built-in static method returns a list of command line flags 
+    for the chosen ``cuda_arch`` value(s).  The flags are intended to
+    be passed to the CUDA compiler driver (i.e., ``nvcc``).
+
+    This method must be explicitly called when you are creating the
+    arguments for your build in order to use the values.
 
 ^^^^^
 Usage
 ^^^^^
 
-In order to use it, just add another base class to your package, for example:
+This helper package can be added to your package by adding it as a base
+class of your package.  For example, you can add it to your
+:ref:`CMakePackage <cmakepackage>`-based package as follows:
 
 .. code-block:: python
+   :emphasize-lines: 1,7-16
 
-    class MyPackage(CMakePackage, CudaPackage):
+    class MyCudaPackage(CMakePackage, CudaPackage):
         ...
         def cmake_args(self):
             spec = self.spec
+            args = []
+            ...
             if '+cuda' in spec:
-                options.append('-DWITH_CUDA=ON')
-                cuda_arch = spec.variants['cuda_arch'].value
+                # Set up the cuda macros needed by the build
+                args.append('-DWITH_CUDA=ON')
+                cuda_arch_list = spec.variants['cuda_arch'].value
+                cuda_arch = cuda_arch_list[0]
                 if cuda_arch != 'none':
-                    options.append('-DCUDA_FLAGS=-arch=sm_{0}'.format(cuda_arch[0]))
+                    args.append('-DCUDA_FLAGS=-arch=sm_{0}'.format(cuda_arch))
             else:
-                options.append('-DWITH_CUDA=OFF')
+                # Ensure build with cuda is disabled
+                args.append('-DWITH_CUDA=OFF')
+            ...
+            return args
+
+assuming only the ``WITH_CUDA`` and ``CUDA_FLAGS`` flags are required.
+You will need to customize options as needed for your build.
+
+This example also illustrates how to check for the ``cuda`` variant using
+``self.spec`` and how to retrieve the ``cuda_arch`` variant's value, which
+is a list, using ``self.spec.variants['cuda_arch'].value``.
+
+With over 70 packages using ``CudaPackage`` as of January 2021 there are
+lots of examples to choose from to get more ideas for using this package.

lib/spack/docs/build_systems/custompackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/intelpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -418,9 +418,13 @@ Adapt the following example. Be sure to maintain the indentation:
    # other content ...
 
      intel-mkl:
-       modules:
-         intel-mkl@2018.2.199  arch=linux-centos6-x86_64:  intel-mkl/18/18.0.2
-         intel-mkl@2018.3.222  arch=linux-centos6-x86_64:  intel-mkl/18/18.0.3
+       externals:
+       - spec: "intel-mkl@2018.2.199  arch=linux-centos6-x86_64"
+         modules:
+         -  intel-mkl/18/18.0.2
+       - spec: "intel-mkl@2018.3.222  arch=linux-centos6-x86_64"
+         modules:
+         -  intel-mkl/18/18.0.3
 
 The version numbers for the ``intel-mkl`` specs defined here correspond to file
 and directory names that Intel uses for its products because they were adopted
@@ -451,12 +455,16 @@ mechanism.
 
    packages:
      intel-parallel-studio:
-       modules:
-         intel-parallel-studio@cluster.2018.2.199 +mkl+mpi+ipp+tbb+daal  arch=linux-centos6-x86_64:  intel/18/18.0.2
-         intel-parallel-studio@cluster.2018.3.222 +mkl+mpi+ipp+tbb+daal  arch=linux-centos6-x86_64:  intel/18/18.0.3
+       externals:
+       - spec: "intel-parallel-studio@cluster.2018.2.199 +mkl+mpi+ipp+tbb+daal  arch=linux-centos6-x86_64"
+         modules:
+         -  intel/18/18.0.2
+       - spec: "intel-parallel-studio@cluster.2018.3.222 +mkl+mpi+ipp+tbb+daal  arch=linux-centos6-x86_64"
+         modules:
+         -  intel/18/18.0.3
        buildable: False
 
-One additional example illustrates the use of ``paths:`` instead of
+One additional example illustrates the use of ``prefix:`` instead of
 ``modules:``, useful when external modulefiles are not available or not
 suitable:
 
@@ -464,13 +472,15 @@ suitable:
 
    packages:
      intel-parallel-studio:
-       paths:
-         intel-parallel-studio@cluster.2018.2.199 +mkl+mpi+ipp+tbb+daal: /opt/intel
-         intel-parallel-studio@cluster.2018.3.222 +mkl+mpi+ipp+tbb+daal: /opt/intel
+       externals:
+       - spec: "intel-parallel-studio@cluster.2018.2.199 +mkl+mpi+ipp+tbb+daal"
+         prefix: /opt/intel
+       - spec: "intel-parallel-studio@cluster.2018.3.222 +mkl+mpi+ipp+tbb+daal"
+         prefix: /opt/intel
        buildable: False
 
 Note that for the Intel packages discussed here, the directory values in the
-``paths:`` entries must be the high-level and typically version-less
+``prefix:`` entries must be the high-level and typically version-less
 "installation directory" that has been used by Intel's product installer.
 Such a directory will typically accumulate various product versions.  Amongst
 them, Spack will select the correct version-specific product directory based on

lib/spack/docs/build_systems/makefilepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/mavenpackage.rst

@@ -0,0 +1,102 @@
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+   Spack Project Developers. See the top-level COPYRIGHT file for details.
+
+   SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+.. _mavenpackage:
+
+------------
+MavenPackage
+------------
+
+Apache Maven is a general-purpose build system that does not rely
+on Makefiles to build software. It is designed for building and
+managing and Java-based project.
+
+^^^^^^
+Phases
+^^^^^^
+
+The ``MavenPackage`` base class comes with the following phases:
+
+#. ``build`` - compile code and package into a JAR file
+#. ``install`` - copy to installation prefix
+
+By default, these phases run:
+
+.. code-block:: console
+
+   $ mvn package
+   $ install . <prefix>
+
+
+^^^^^^^^^^^^^^^
+Important files
+^^^^^^^^^^^^^^^
+
+Maven packages can be identified by the presence of a ``pom.xml`` file.
+This file lists dependencies and other metadata about the project.
+There may also be configuration files in the ``.mvn`` directory.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Build system dependencies
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Maven requires the ``mvn`` executable to build the project. It also
+requires Java at both build- and run-time. Because of this, the base
+class automatically adds the following dependencies:
+
+.. code-block:: python
+
+   depends_on('java', type=('build', 'run'))
+   depends_on('maven', type='build')
+
+
+In the ``pom.xml`` file, you may see sections like:
+
+.. code-block:: xml
+
+   <requireJavaVersion>
+      <version>[1.7,)</version>
+   </requireJavaVersion>
+   <requireMavenVersion>
+      <version>[3.5.4,)</version>
+   </requireMavenVersion>
+
+
+This specifies the versions of Java and Maven that are required to
+build the package. See
+https://docs.oracle.com/middleware/1212/core/MAVEN/maven_version.htm#MAVEN402
+for a description of this version range syntax. In this case, you
+should add:
+
+.. code-block:: python
+
+   depends_on('java@7:', type='build')
+   depends_on('maven@3.5.4:', type='build')
+
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Passing arguments to the build phase
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The default build and install phases should be sufficient to install
+most packages. However, you may want to pass additional flags to
+the build phase. For example:
+
+.. code-block:: python
+
+   def build_args(self):
+       return [
+           '-Pdist,native',
+           '-Dtar',
+           '-Dmaven.javadoc.skip=true'
+       ]
+
+
+^^^^^^^^^^^^^^^^^^^^^^
+External documentation
+^^^^^^^^^^^^^^^^^^^^^^
+
+For more information on the Maven build system, see:
+https://maven.apache.org/index.html

lib/spack/docs/build_systems/mesonpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/octavepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/perlpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -120,8 +120,6 @@ so ``PerlPackage`` contains:
 
    extends('perl')
 
-   depends_on('perl', type=('build', 'run'))
-
 
 If your package requires a specific version of Perl, you should
 specify this.

lib/spack/docs/build_systems/pythonpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -23,20 +23,11 @@ can be overridden:
 * ``build_ext``
 * ``build_clib``
 * ``build_scripts``
-* ``clean``
 * ``install``
 * ``install_lib``
 * ``install_headers``
 * ``install_scripts``
 * ``install_data``
-* ``sdist``
-* ``register``
-* ``bdist``
-* ``bdist_dumb``
-* ``bdist_rpm``
-* ``bdist_wininst``
-* ``upload``
-* ``check``
 
 These are all standard ``setup.py`` commands and can be found by running:
 
@@ -55,7 +46,7 @@ If for whatever reason you need to run more phases, simply modify your
 
 .. code-block:: python
 
-   phases = ['build_ext', 'install', 'bdist']
+   phases = ['build_ext', 'install']
 
 
 Each phase provides a function ``<phase>`` that runs:
@@ -81,6 +72,24 @@ you'll need to define a function for it like so:
        self.setup_py('configure')
 
 
+^^^^^^
+Wheels
+^^^^^^
+
+Some Python packages are closed-source and distributed as wheels.
+Instead of using the ``PythonPackage`` base class, you should extend
+the ``Package`` base class and implement the following custom installation
+procedure:
+
+.. code-block:: python
+
+   def install(self, spec, prefix):
+       pip = which('pip')
+       pip('install', self.stage.archive_file, '--prefix={0}'.format(prefix))
+
+
+This will require a dependency on pip, as mentioned below.
+
 ^^^^^^^^^^^^^^^
 Important files
 ^^^^^^^^^^^^^^^
@@ -95,9 +104,30 @@ file should be considered to be the truth. As dependencies are added or
 removed, the documentation is much more likely to become outdated than
 the ``setup.py``.
 
-^^^^^^^^^^^^^^^^^^^^^^^
-Finding Python packages
-^^^^^^^^^^^^^^^^^^^^^^^
+The Python ecosystem has evolved significantly over the years. Before
+setuptools became popular, most packages listed their dependencies in a
+``requirements.txt`` file. Once setuptools took over, these dependencies
+were listed directly in the ``setup.py``. Newer PEPs introduced additional
+files, like ``setup.cfg`` and ``pyproject.toml``. You should look out for
+all of these files, as they may all contain important information about
+package dependencies.
+
+Some Python packages are closed-source and are distributed as Python
+wheels. For example, ``py-azureml-sdk`` downloads a ``.whl`` file. This
+file is simply a zip file, and can be extracted using:
+
+.. code-block:: console
+
+   $ unzip *.whl
+
+
+The zip file will not contain a ``setup.py``, but it will contain a
+``METADATA`` file which contains all the information you need to
+write a ``package.py`` build recipe.
+
+^^^^
+PyPI
+^^^^
 
 The vast majority of Python packages are hosted on PyPI - The Python
 Package Index. ``pip`` only supports packages hosted on PyPI, making
@@ -105,8 +135,29 @@ it the only option for developers who want a simple installation.
 Search for "PyPI <package-name>" to find the download page. Note that
 some pages are versioned, and the first result may not be the newest
 version. Click on the "Latest Version" button to the top right to see
-if a newer version is available. The download page is usually at:
-https://pypi.org/project/<package-name>
+if a newer version is available. The download page is usually at::
+
+   https://pypi.org/project/<package-name>
+
+
+Since PyPI is so common, the ``PythonPackage`` base class has a
+``pypi`` attribute that can be set. Once set, ``pypi`` will be used
+to define the ``homepage``, ``url``, and ``list_url``. For example,
+the following:
+
+.. code-block:: python
+
+   homepage = 'https://pypi.org/project/setuptools/'
+   url      = 'https://pypi.org/packages/source/s/setuptools/setuptools-49.2.0.zip'
+   list_url = 'https://pypi.org/simple/setuptools/'
+
+
+is equivalent to:
+
+.. code-block:: python
+
+   pypi = 'setuptools/setuptools-49.2.0.zip'
+
 
 ^^^^^^^^^^^
 Description
@@ -144,50 +195,38 @@ also get the homepage on the command-line by running:
 URL
 ^^^
 
-You may have noticed that Spack allows you to add multiple versions of
-the same package without adding multiple versions of the download URL.
-It does this by guessing what the version string in the URL is and
-replacing this with the requested version. Obviously, if Spack cannot
-guess the version correctly, or if non-version-related things change
-in the URL, Spack cannot substitute the version properly.
+If ``pypi`` is set as mentioned above, ``url`` and ``list_url`` will
+be automatically set for you. If both ``.tar.gz`` and ``.zip`` versions
+are available, ``.tar.gz`` is preferred. If some releases offer both
+``.tar.gz`` and ``.zip`` versions, but some only offer ``.zip`` versions,
+use ``.zip``.
 
-Once upon a time, PyPI offered nice, simple download URLs like:
-https://pypi.python.org/packages/source/n/numpy/numpy-1.13.1.zip
+Some Python packages are closed-source and do not ship ``.tar.gz`` or ``.zip``
+files on either PyPI or GitHub. If this is the case, you can still download
+and install a Python wheel. For example, ``py-azureml-sdk`` is closed source
+and can be downloaded from::
 
-As you can see, the version is 1.13.1. It probably isn't hard to guess
-what URL to use to download version 1.12.0, and Spack was perfectly
-capable of performing this calculation.
+   https://pypi.io/packages/py3/a/azureml_sdk/azureml_sdk-1.11.0-py3-none-any.whl
 
-However, PyPI switched to a new download URL format:
-https://pypi.python.org/packages/c0/3a/40967d9f5675fbb097ffec170f59c2ba19fc96373e73ad47c2cae9a30aed/numpy-1.13.1.zip#md5=2c3c0f4edf720c3a7b525dacc825b9ae
 
-and more recently:
-https://files.pythonhosted.org/packages/b0/2b/497c2bb7c660b2606d4a96e2035e92554429e139c6c71cdff67af66b58d2/numpy-1.14.3.zip
+You may see Python-specific or OS-specific URLs. Note that when you add a
+``.whl`` URL, you should add ``expand=False`` to ensure that Spack doesn't
+try to extract the wheel:
 
-As you can imagine, it is impossible for Spack to guess what URL to
-use to download version 1.12.0 given this URL. There is a solution,
-however. PyPI offers a new hidden interface for downloading
-Python packages that does not include a hash in the URL:
-https://pypi.io/packages/source/n/numpy/numpy-1.13.1.zip
+.. code-block:: python
 
-This URL redirects to the files.pythonhosted.org URL. The general syntax for
-this pypi.io URL is:
-https://pypi.io/packages/source/<first-letter-of-name>/<name>/<name>-<version>.<extension>
+   version('1.11.0', sha256='d8c9d24ea90457214d798b0d922489863dad518adde3638e08ef62de28fb183a', expand=False)
 
-Please use the pypi.io URL instead of the pypi.python.org URL. If both
-``.tar.gz`` and ``.zip`` versions are available, ``.tar.gz`` is preferred.
-If some releases offer both ``.tar.gz`` and ``.zip`` versions, but some
-only offer ``.zip`` versions, use ``.zip``.
 
 """""""""""""""
 PyPI vs. GitHub
 """""""""""""""
 
-Many packages are hosted on PyPI, but are developed on GitHub and other
+Many packages are hosted on PyPI, but are developed on GitHub or another
 version control systems. The tarball can be downloaded from either
 location, but PyPI is preferred for the following reasons:
 
-#. PyPI contains the bare minimum of files to install the package.
+#. PyPI contains the bare minimum number of files needed to install the package.
 
    You may notice that the tarball you download from PyPI does not
    have the same checksum as the tarball you download from GitHub.
@@ -224,25 +263,6 @@ location, but PyPI is preferred for the following reasons:
    PyPI is nice because it makes it physically impossible to
    re-release the same version of a package with a different checksum.
 
-There are some reasons to prefer downloading from GitHub:
-
-#. The GitHub tarball may contain unit tests
-
-   As previously mentioned, the PyPI tarball contains the bare minimum
-   of files to install the package. Unless explicitly specified by the
-   developers, it will not contain development files like unit tests.
-   If you desire to run the unit tests during installation, you should
-   use the GitHub tarball instead.
-
-#. Spack does not yet support ``spack versions`` and ``spack checksum``
-   with PyPI URLs
-
-   These commands work just fine with GitHub URLs. This is a minor
-   annoyance, not a reason to prefer GitHub over PyPI.
-
-If you really want to run these unit tests, no one will stop you from
-submitting a PR for a new package that downloads from GitHub.
-
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 Build system dependencies
 ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -262,26 +282,26 @@ mentions that Python 3 is required, this can be specified as:
 
 .. code-block:: python
 
-   depends_on('python@3:', type=('build', 'run')
+   depends_on('python@3:', type=('build', 'run'))
 
 
 If Python 2 is required, this would look like:
 
 .. code-block:: python
 
-   depends_on('python@:2', type=('build', 'run')
+   depends_on('python@:2', type=('build', 'run'))
 
 
 If Python 2.7 is the only version that works, you can use:
 
 .. code-block:: python
 
-   depends_on('python@2.7:2.8', type=('build', 'run')
+   depends_on('python@2.7:2.8', type=('build', 'run'))
 
 
 The documentation may not always specify supported Python versions.
-Another place to check is in the ``setup.py`` file. Look for a line
-containing ``python_requires``. An example from
+Another place to check is in the ``setup.py`` or ``setup.cfg`` file.
+Look for a line containing ``python_requires``. An example from
 `py-numpy <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/py-numpy/package.py>`_
 looks like:
 
@@ -290,7 +310,7 @@ looks like:
    python_requires='>=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*'
 
 
-More commonly, you will find a version check at the top of the file:
+You may also find a version check at the top of the ``setup.py``:
 
 .. code-block:: python
 
@@ -305,6 +325,39 @@ This can be converted to Spack's spec notation like so:
    depends_on('python@2.7:2.8,3.4:', type=('build', 'run'))
 
 
+If you are writing a recipe for a package that only distributes
+wheels, look for a section in the ``METADATA`` file that looks like::
+
+   Requires-Python: >=3.5,<4
+
+
+This would be translated to:
+
+.. code-block:: python
+
+   extends('python')
+   depends_on('python@3.5:3.999', type=('build', 'run'))
+
+
+Many ``setup.py`` or ``setup.cfg`` files also contain information like::
+
+   Programming Language :: Python :: 2
+   Programming Language :: Python :: 2.6
+   Programming Language :: Python :: 2.7
+   Programming Language :: Python :: 3
+   Programming Language :: Python :: 3.3
+   Programming Language :: Python :: 3.4
+   Programming Language :: Python :: 3.5
+   Programming Language :: Python :: 3.6
+
+
+This is a list of versions of Python that the developer likely tests.
+However, you should not use this to restrict the versions of Python
+the package uses unless one of the two former methods (``python_requires``
+or ``sys.version_info``) is used. There is no logic in setuptools
+that prevents the package from building for Python versions not in
+this list, and often new releases like Python 3.7 or 3.8 work just fine.
+
 """"""""""
 setuptools
 """"""""""
@@ -317,7 +370,7 @@ Most notably, there was no way to list a project's dependencies
 with distutils. Along came setuptools, a non-builtin build system
 designed to overcome the limitations of distutils. Both projects
 use a similar API, making the transition easy while adding much
-needed functionality. Today, setuptools is used in around 75% of
+needed functionality. Today, setuptools is used in around 90% of
 the Python packages in Spack.
 
 Since setuptools isn't built-in to Python, you need to add it as a
@@ -360,6 +413,20 @@ run-time. This can be specified as:
    depends_on('py-setuptools', type='build')
 
 
+"""
+pip
+"""
+
+Packages distributed as Python wheels will require an extra dependency
+on pip:
+
+.. code-block:: python
+
+   depends_on('py-pip', type='build')
+
+
+We will use pip to install the actual wheel.
+
 """"""
 cython
 """"""
@@ -383,6 +450,12 @@ where speed is crucial. There is no reason why someone would not
 want an optimized version of a library instead of the pure-Python
 version.
 
+Note that some release tarballs come pre-cythonized, and cython is
+not needed as a dependency. However, this is becoming less common
+as Python continues to evolve and developers discover that cythonized
+sources are no longer compatible with newer versions of Python and
+need to be re-cythonized.
+
 ^^^^^^^^^^^^^^^^^^^
 Python dependencies
 ^^^^^^^^^^^^^^^^^^^
@@ -429,21 +502,33 @@ Obviously, this means that ``py-numpy`` is a dependency.
 
 If the package uses ``setuptools``, check for the following clues:
 
+* ``python_requires``
+
+  As mentioned above, this specifies which versions of Python are
+  required.
+
+* ``setup_requires``
+
+  These packages are usually only needed at build-time, so you can
+  add them with ``type='build'``.
+
 * ``install_requires``
 
-  These packages are required for installation.
+  These packages are required for building and installation. You can
+  add them with ``type=('build', 'run')``.
 
 * ``extra_requires``
 
   These packages are optional dependencies that enable additional
   functionality. You should add a variant that optionally adds these
-  dependencies.
+  dependencies. This variant should be False by default.
 
 * ``test_requires``
 
   These are packages that are required to run the unit tests for the
   package. These dependencies can be specified using the
-  ``type='test'`` dependency type.
+  ``type='test'`` dependency type. However, the PyPI tarballs rarely
+  contain unit tests, so there is usually no reason to add these.
 
 In the root directory of the package, you may notice a
 ``requirements.txt`` file. It may look like this file contains a list
@@ -461,13 +546,37 @@ sphinx. If you can't find any information about the package's
 dependencies, you can take a look in ``requirements.txt``, but be sure
 not to add test or documentation dependencies.
 
+Newer PEPs have added alternative ways to specify a package's dependencies.
+If you don't see any dependencies listed in the ``setup.py``, look for a
+``setup.cfg`` or ``pyproject.toml``. These files can be used to store the
+same ``install_requires`` information that ``setup.py`` used to use.
+
+If you are write a recipe for a package that only distributes wheels,
+check the ``METADATA`` file for lines like::
+
+   Requires-Dist: azureml-core (~=1.11.0)
+   Requires-Dist: azureml-dataset-runtime[fuse] (~=1.11.0)
+   Requires-Dist: azureml-train (~=1.11.0)
+   Requires-Dist: azureml-train-automl-client (~=1.11.0)
+   Requires-Dist: azureml-pipeline (~=1.11.0)
+   Provides-Extra: accel-models
+   Requires-Dist: azureml-accel-models (~=1.11.0); extra == 'accel-models'
+   Provides-Extra: automl
+   Requires-Dist: azureml-train-automl (~=1.11.0); extra == 'automl'
+
+
+Lines that use ``Requires-Dist`` are similar to ``install_requires``.
+Lines that use ``Provides-Extra`` are similar to ``extra_requires``,
+and you can add a variant for those dependencies. The ``~=1.11.0``
+syntax is equivalent to ``1.11.0:1.11.999``.
+
 """"""""""
 setuptools
 """"""""""
 
 Setuptools is a bit of a special case. If a package requires setuptools
 at run-time, how do they express this? They could add it to
-``install_requires``, but setuptools is imported long before this and
+``install_requires``, but setuptools is imported long before this and is
 needed to read this line. And since you can't install the package
 without setuptools, the developers assume that setuptools will already
 be there, so they never mention when it is required. We don't want to
@@ -475,7 +584,8 @@ add run-time dependencies if they aren't needed, so you need to
 determine whether or not setuptools is needed. Grep the installation
 directory for any files containing a reference to ``setuptools`` or
 ``pkg_resources``. Both modules come from ``py-setuptools``.
-``pkg_resources`` is particularly common in scripts in ``prefix/bin``.
+``pkg_resources`` is particularly common in scripts found in
+``prefix/bin``.
 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Passing arguments to setup.py
@@ -549,47 +659,65 @@ a "package" is a directory containing files like:
    foo/baz.py
 
 
-whereas a "module" is a single Python file. Since ``find_packages``
-only returns packages, you'll have to determine the correct module
-names yourself. You can now add these packages and modules to the
-package like so:
+whereas a "module" is a single Python file.
+
+The ``PythonPackage`` base class automatically detects these module
+names for you. If, for whatever reason, the module names detected
+are wrong, you can provide the names yourself by overriding
+``import_modules`` like so:
 
 .. code-block:: python
 
    import_modules = ['six']
 
 
-When you run ``spack install --test=root py-six``, Spack will attempt
-to import the ``six`` module after installation.
+Sometimes the list of module names to import depends on how the
+package was built. For example, the ``py-pyyaml`` package has a
+``+libyaml`` variant that enables the build of a faster optimized
+version of the library. If the user chooses ``~libyaml``, only the
+``yaml`` library will be importable. If the user chooses ``+libyaml``,
+both the ``yaml`` and ``yaml.cyaml`` libraries will be available.
+This can be expressed like so:
 
-These tests most often catch missing dependencies and non-RPATHed
+.. code-block:: python
+
+   @property
+   def import_modules(self):
+       modules = ['yaml']
+
+       if '+libyaml' in self.spec:
+           modules.append('yaml.cyaml')
+
+       return modules
+
+
+These tests often catch missing dependencies and non-RPATHed
 libraries. Make sure not to add modules/packages containing the word
-"test", as these likely won't end up in installation directory.
+"test", as these likely won't end up in the installation directory,
+or may require test dependencies like pytest to be installed.
+
+These tests can be triggered by running ``spack install --test=root``
+or by running ``spack test run`` after the installation has finished.
 
 """"""""""
 Unit tests
 """"""""""
 
 The package you want to install may come with additional unit tests.
-By default, Spack runs:
-
-.. code-block:: console
-
-   $ python setup.py test
-
-
-if it detects that the ``setup.py`` file supports a ``test`` phase.
-You can add additional build-time or install-time tests by overriding
-``test`` and ``installtest``, respectively. For example, ``py-numpy``
-adds:
+You can add additional build-time or install-time tests by adding
+additional testing functions. For example, ``py-numpy`` adds:
 
 .. code-block:: python
 
+   @run_after('install')
+   @on_package_attributes(run_tests=True)
    def install_test(self):
-        with working_dir('..'):
-            python('-c', 'import numpy; numpy.test("full", verbose=2)')
+       with working_dir('spack-test', create=True):
+           python('-c', 'import numpy; numpy.test("full", verbose=2)')
 
 
+These tests can be triggered by running ``spack install --test=root``.
+
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Setup file in a sub-directory
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -629,7 +757,7 @@ PythonPackage vs. packages that use Python
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 There are many packages that make use of Python, but packages that depend
-on Python are not necessarily ``PythonPackages``.
+on Python are not necessarily ``PythonPackage``'s.
 
 """""""""""""""""""""""
 Choosing a build system
@@ -651,6 +779,8 @@ that the package uses the ``PythonPackage`` build system. However, there
 are occasionally packages that use ``PythonPackage`` that shouldn't
 start with ``py-``. For example:
 
+* awscli
+* aws-parallelcluster
 * busco
 * easybuild
 * httpie
@@ -724,8 +854,8 @@ and ``pip`` may be a perfectly valid alternative to using Spack. The
 main advantage of Spack over ``pip`` is its ability to compile
 non-Python dependencies. It can also build cythonized versions of a
 package or link to an optimized BLAS/LAPACK library like MKL,
-resulting in calculations that run orders of magnitude faster.
-Spack does not offer a significant advantage to other python-management
+resulting in calculations that run orders of magnitudes faster.
+Spack does not offer a significant advantage over other python-management
 systems for installing and using tools like flake8 and sphinx.
 But if you need packages with non-Python dependencies like
 numpy and scipy, Spack will be very valuable to you.
@@ -736,8 +866,9 @@ non-Python dependencies. Anaconda contains many Python packages that
 are not yet in Spack, and Spack contains many Python packages that are
 not yet in Anaconda. The main advantage of Spack over Anaconda is its
 ability to choose a specific compiler and BLAS/LAPACK or MPI library.
-Spack also has better platform support for supercomputers. On the
-other hand, Anaconda offers Windows support.
+Spack also has better platform support for supercomputers, and can build
+optimized binaries for your specific microarchitecture. On the other hand,
+Anaconda offers Windows support.
 
 ^^^^^^^^^^^^^^^^^^^^^^
 External documentation

lib/spack/docs/build_systems/qmakepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -108,6 +108,19 @@ override the ``qmake_args`` method like so:
 
 This method can be used to pass flags as well as variables.
 
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+``*.pro`` file in a sub-directory
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If the ``*.pro`` file used to tell QMake how to build the package is
+found in a sub-directory, you can tell Spack to run all phases in this
+sub-directory by adding the following to the package:
+
+.. code-block:: python
+
+   build_directory = 'src'
+
+
 ^^^^^^^^^^^^^^^^^^^^^^
 External documentation
 ^^^^^^^^^^^^^^^^^^^^^^

lib/spack/docs/build_systems/rocmpackage.rst

@@ -0,0 +1,122 @@
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+   Spack Project Developers. See the top-level COPYRIGHT file for details.
+
+   SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+.. _rocmpackage:
+
+-----------
+ROCmPackage
+-----------
+
+The ``ROCmPackage`` is not a build system but a helper package. Like ``CudaPackage``,
+it provides standard variants, dependencies, and conflicts to facilitate building
+packages using GPUs though for AMD in this case.
+
+You can find the source for this package (and suggestions for setting up your
+``compilers.yaml`` and ``packages.yaml`` files) at
+`<https://github.com/spack/spack/blob/develop/lib/spack/spack/build_systems/rocm.py>`__.
+
+^^^^^^^^
+Variants
+^^^^^^^^
+
+This package provides the following variants:
+
+* **rocm**
+
+  This variant is used to enable/disable building with ``rocm``.  
+  The default is disabled (or ``False``).
+
+* **amdgpu_target**
+
+  This variant supports the optional specification of the AMD GPU architecture.
+  Valid values are the names of the GPUs (e.g., ``gfx701``), which are maintained
+  in the ``amdgpu_targets`` property.
+
+^^^^^^^^^^^^
+Dependencies
+^^^^^^^^^^^^
+
+This package defines basic ``rocm`` dependencies, including ``llvm`` and ``hip``.
+
+^^^^^^^^^
+Conflicts
+^^^^^^^^^
+
+Conflicts are used to prevent builds with known bugs or issues. This package
+already requires that the ``amdgpu_target`` always be specified for ``rocm``
+builds. It also defines a conflict that prevents builds with an ``amdgpu_target``
+when ``rocm`` is disabled.
+
+Refer to `Conflicts <https://spack.readthedocs.io/en/latest/packaging_guide.html?highlight=conflicts#conflicts>`__
+for more information on package conflicts.
+
+^^^^^^^
+Methods
+^^^^^^^
+
+This package provides one custom helper method, which is used to build
+standard AMD hip compiler flags.
+
+**hip_flags**
+
+    This built-in static method returns the appropriately formatted
+    ``--amdgpu-target`` build option for ``hipcc``.
+
+    This method must be explicitly called when you are creating the
+    arguments for your build in order to use the values.
+
+^^^^^
+Usage
+^^^^^
+
+This helper package can be added to your package by adding it as a base
+class of your package.  For example, you can add it to your
+:ref:`CMakePackage <cmakepackage>`-based package as follows:
+
+.. code-block:: python
+   :emphasize-lines: 1,3-7,14-25
+
+    class MyRocmPackage(CMakePackage, ROCmPackage):
+        ...
+        # Ensure +rocm and amdgpu_targets are passed to dependencies
+        depends_on('mydeppackage', when='+rocm')
+        for val in ROCmPackage.amdgpu_targets:
+            depends_on('mydeppackage amdgpu_target={0}'.format(val),
+                       when='amdgpu_target={0}'.format(val))
+        ...
+
+        def cmake_args(self):
+            spec = self.spec
+            args = []
+            ...
+            if '+rocm' in spec:
+                # Set up the hip macros needed by the build
+                args.extend([
+                    '-DENABLE_HIP=ON',
+                    '-DHIP_ROOT_DIR={0}'.format(spec['hip'].prefix])
+                rocm_archs = spec.variants['amdgpu_target'].value
+                if 'none' not in rocm_archs:
+                    args.append('-DHIP_HIPCC_FLAGS=--amdgpu-target={0}'
+                                .format(",".join(rocm_archs)))
+            else:
+                # Ensure build with hip is disabled
+                args.append('-DENABLE_HIP=OFF')
+            ...
+            return args
+        ...
+
+assuming only on the ``ENABLE_HIP``, ``HIP_ROOT_DIR``, and ``HIP_HIPCC_FLAGS``
+macros are required to be set and the only dependency needing rocm options
+is ``mydeppackage``. You will need to customize the flags as needed for your
+build.
+
+This example also illustrates how to check for the ``rocm`` variant using
+``self.spec`` and how to retrieve the ``amdgpu_target`` variant's value
+using ``self.spec.variants['amdgpu_target'].value``.
+
+All five packages using ``ROCmPackage`` as of January 2021 also use the
+:ref:`CudaPackage <cudapackage>`. So it is worth looking at those packages
+to get ideas for creating a package that can support both ``cuda`` and
+``rocm``.

lib/spack/docs/build_systems/rpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -138,7 +138,6 @@ every R package needs this, the ``RPackage`` base class contains:
 .. code-block:: python
 
    extends('r')
-   depends_on('r', type=('build', 'run'))
 
 
 Take a close look at the homepage for ``caret``. If you look at the
@@ -298,8 +297,8 @@ like so:
 
 .. code-block:: python
 
-   def configure_args(self, spec, prefix):
-       mpi_name = spec['mpi'].name
+   def configure_args(self):
+       mpi_name = self.spec['mpi'].name
 
        # The type of MPI. Supported values are:
        # OPENMPI, LAM, MPICH, MPICH2, or CRAY

lib/spack/docs/build_systems/rubypackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -12,5 +12,172 @@ RubyPackage
 Like Perl, Python, and R, Ruby has its own build system for
 installing Ruby gems.
 
-This build system is a work-in-progress. See
-https://github.com/spack/spack/pull/3127 for more information.
+^^^^^^
+Phases
+^^^^^^
+
+The ``RubyPackage`` base class provides the following phases that
+can be overridden:
+
+#. ``build`` - build everything needed to install
+#. ``install`` - install everything from build directory
+
+For packages that come with a ``*.gemspec`` file, these phases run:
+
+.. code-block:: console
+
+   $ gem build *.gemspec
+   $ gem install *.gem
+
+
+For packages that come with a ``Rakefile`` file, these phases run:
+
+.. code-block:: console
+
+   $ rake package
+   $ gem install *.gem
+
+
+For packages that come pre-packaged as a ``*.gem`` file, the build
+phase is skipped and the install phase runs:
+
+.. code-block:: console
+
+   $ gem install *.gem
+
+
+These are all standard ``gem`` commands and can be found by running:
+
+.. code-block:: console
+
+   $ gem help commands
+
+
+For packages that only distribute ``*.gem`` files, these files can be
+downloaded with the ``expand=False`` option in the ``version`` directive.
+The build phase will be automatically skipped.
+
+^^^^^^^^^^^^^^^
+Important files
+^^^^^^^^^^^^^^^
+
+When building from source, Ruby packages can be identified by the
+presence of any of the following files:
+
+* ``*.gemspec``
+* ``Rakefile``
+* ``setup.rb`` (not yet supported)
+
+However, not all Ruby packages are released as source code. Some are only
+released as ``*.gem`` files. These files can be extracted using:
+
+.. code-block:: console
+
+   $ gem unpack *.gem
+
+
+^^^^^^^^^^^
+Description
+^^^^^^^^^^^
+
+The ``*.gemspec`` file may contain something like:
+
+.. code-block:: ruby
+
+   summary = 'An implementation of the AsciiDoc text processor and publishing toolchain'
+   description = 'A fast, open source text processor and publishing toolchain for converting AsciiDoc content to HTML 5, DocBook 5, and other formats.'
+
+
+Either of these can be used for the description of the Spack package.
+
+^^^^^^^^
+Homepage
+^^^^^^^^
+
+The ``*.gemspec`` file may contain something like:
+
+.. code-block:: ruby
+
+   homepage = 'https://asciidoctor.org'
+
+
+This should be used as the official homepage of the Spack package.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Build system dependencies
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+All Ruby packages require Ruby at build and run-time. For this reason,
+the base class contains:
+
+.. code-block:: python
+
+   extends('ruby')
+
+
+The ``*.gemspec`` file may contain something like:
+
+.. code-block:: ruby
+
+   required_ruby_version = '>= 2.3.0'
+
+
+This can be added to the Spack package using:
+
+.. code-block:: python
+
+   depends_on('ruby@2.3.0:', type=('build', 'run'))
+
+
+^^^^^^^^^^^^^^^^^
+Ruby dependencies
+^^^^^^^^^^^^^^^^^
+
+When you install a package with ``gem``, it reads the ``*.gemspec``
+file in order to determine the dependencies of the package.
+If the dependencies are not yet installed, ``gem`` downloads them
+and installs them for you. This may sound convenient, but Spack
+cannot rely on this behavior for two reasons:
+
+#. Spack needs to be able to install packages on air-gapped networks.
+
+   If there is no internet connection, ``gem`` can't download the
+   package dependencies. By explicitly listing every dependency in
+   the ``package.py``, Spack knows what to download ahead of time.
+
+#. Duplicate installations of the same dependency may occur.
+
+   Spack supports *activation* of Ruby extensions, which involves
+   symlinking the package installation prefix to the Ruby installation
+   prefix. If your package is missing a dependency, that dependency
+   will be installed to the installation directory of the same package.
+   If you try to activate the package + dependency, it may cause a
+   problem if that package has already been activated.
+
+For these reasons, you must always explicitly list all dependencies.
+Although the documentation may list the package's dependencies,
+often the developers assume people will use ``gem`` and won't have to
+worry about it. Always check the ``*.gemspec`` file to find the true
+dependencies.
+
+Check for the following clues in the ``*.gemspec`` file:
+
+* ``add_runtime_dependency``
+
+  These packages are required for installation.
+
+* ``add_dependency``
+
+  This is an alias for ``add_runtime_dependency``
+
+* ``add_development_dependency``
+
+  These packages are optional dependencies used for development.
+  They should not be added as dependencies of the package.
+
+^^^^^^^^^^^^^^^^^^^^^^
+External documentation
+^^^^^^^^^^^^^^^^^^^^^^
+
+For more information on Ruby packaging, see:
+https://guides.rubygems.org/

lib/spack/docs/build_systems/sconspackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/build_systems/sippackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -93,10 +93,17 @@ in the site-packages directory:
    $ python
    >>> import setuptools
    >>> setuptools.find_packages()
-   ['QtPy5']
+   [
+       'PyQt5', 'PyQt5.QtCore', 'PyQt5.QtGui', 'PyQt5.QtHelp',
+       'PyQt5.QtMultimedia', 'PyQt5.QtMultimediaWidgets', 'PyQt5.QtNetwork',
+       'PyQt5.QtOpenGL', 'PyQt5.QtPrintSupport', 'PyQt5.QtQml',
+       'PyQt5.QtQuick', 'PyQt5.QtSvg', 'PyQt5.QtTest', 'PyQt5.QtWebChannel',
+       'PyQt5.QtWebSockets', 'PyQt5.QtWidgets', 'PyQt5.QtXml',
+       'PyQt5.QtXmlPatterns'
+    ]
 
 
-Large, complex packages like ``QtPy5`` will return a long list of
+Large, complex packages like ``py-pyqt5`` will return a long list of
 packages, while other packages may return an empty list. These packages
 only install a single ``foo.py`` file. In Python packaging lingo,
 a "package" is a directory containing files like:
@@ -108,21 +115,25 @@ a "package" is a directory containing files like:
    foo/baz.py
 
 
-whereas a "module" is a single Python file. Since ``find_packages``
-only returns packages, you'll have to determine the correct module
-names yourself. You can now add these packages and modules to the
-package like so:
+whereas a "module" is a single Python file.
+
+The ``SIPPackage`` base class automatically detects these module
+names for you. If, for whatever reason, the module names detected
+are wrong, you can provide the names yourself by overriding
+``import_modules`` like so:
 
 .. code-block:: python
 
    import_modules = ['PyQt5']
 
 
-When you run ``spack install --test=root py-pyqt5``, Spack will attempt
-to import the ``PyQt5`` module after installation.
+These tests often catch missing dependencies and non-RPATHed
+libraries. Make sure not to add modules/packages containing the word
+"test", as these likely won't end up in the installation directory,
+or may require test dependencies like pytest to be installed.
 
-These tests most often catch missing dependencies and non-RPATHed
-libraries.
+These tests can be triggered by running ``spack install --test=root``
+or by running ``spack test run`` after the installation has finished.
 
 ^^^^^^^^^^^^^^^^^^^^^^
 External documentation

lib/spack/docs/build_systems/wafpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/chain.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/conf.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -128,7 +128,7 @@ def setup(sphinx):
 
 # General information about the project.
 project = u'Spack'
-copyright = u'2013-2019, Lawrence Livermore National Laboratory.'
+copyright = u'2013-2021, Lawrence Livermore National Laboratory.'
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the

lib/spack/docs/config_yaml.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -99,7 +99,7 @@ username is not already in the path, Spack will append the value of ``$user`` to
 the selected ``build_stage`` path.
 
 .. warning:: We highly recommend specifying ``build_stage`` paths that
-   distinguish between staging and other activities to ensure 
+   distinguish between staging and other activities to ensure
    ``spack clean`` does not inadvertently remove unrelated files.
    Spack prepends ``spack-stage-`` to temporary staging directory names to
    reduce this risk.  Using a combination of ``spack`` and or ``stage`` in
@@ -223,7 +223,7 @@ To build all software in serial, set ``build_jobs`` to 1.
 --------------------
 
 When set to ``true`` Spack will use ccache to cache compiles. This is
-useful specifically in two cases: (1) when using ``spack setup``, and (2)
+useful specifically in two cases: (1) when using ``spack dev-build``, and (2)
 when building the same package with many different variants. The default is
 ``false``.
 

lib/spack/docs/configuration.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/containers.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -9,28 +9,48 @@
 Container Images
 ================
 
-Spack can be an ideal tool to setup images for containers since all the
-features discussed in :ref:`environments` can greatly help to manage
-the installation of software during the image build process. Nonetheless,
-building a production image from scratch still requires a lot of
-boilerplate to:
+Spack :ref:`environments` are a great tool to create container images, but
+preparing one that is suitable for production requires some more boilerplate
+than just:
 
-- Get Spack working within the image, possibly running as root
-- Minimize the physical size of the software installed
-- Properly update the system software in the base image
+.. code-block:: docker
 
-To facilitate users with these tedious tasks, Spack provides a command
-to automatically generate recipes for container images based on
-Environments:
+   COPY spack.yaml /environment
+   RUN spack -e /environment install
+
+Additional actions may be needed to minimize the size of the
+container, or to update the system software that is installed in the base
+image, or to set up a proper entrypoint to run the image. These tasks are
+usually both necessary and repetitive, so Spack comes with a command
+to generate recipes for container images starting from a ``spack.yaml``.
+
+--------------------
+A Quick Introduction
+--------------------
+
+Consider having a Spack environment like the following:
+
+.. code-block:: yaml
+
+   spack:
+     specs:
+     - gromacs+mpi
+     - mpich
+
+Producing a ``Dockerfile`` from it is as simple as moving to the directory
+where the ``spack.yaml`` file is stored and giving the following command:
 
 .. code-block:: console
 
-   $ ls
-   spack.yaml
+   $ spack containerize > Dockerfile
+
+The ``Dockerfile`` that gets created uses multi-stage builds and
+other techniques to minimize the size of the final image:
+
+.. code-block:: docker
 
-   $ spack containerize
    # Build stage with Spack pre-installed and ready to be used
-   FROM spack/centos7:latest as builder
+   FROM spack/ubuntu-bionic:latest as builder
 
    # What we want to install and how we want to install it
    # is specified in a manifest file (spack.yaml)
@@ -45,7 +65,7 @@ Environments:
    &&   echo "  view: /opt/view") > /opt/spack-environment/spack.yaml
 
    # Install the software, remove unnecessary deps
-   RUN cd /opt/spack-environment && spack install && spack gc -y
+   RUN cd /opt/spack-environment && spack env activate . && spack install --fail-fast && spack gc -y
 
    # Strip all the binaries
    RUN find -L /opt/view/* -type f -exec readlink -f '{}' \; | \
@@ -58,38 +78,34 @@ Environments:
    RUN cd /opt/spack-environment && \
        spack env activate --sh -d . >> /etc/profile.d/z10_spack_environment.sh
 
-
    # Bare OS image to run the installed executables
-   FROM centos:7
+   FROM ubuntu:18.04
 
    COPY --from=builder /opt/spack-environment /opt/spack-environment
    COPY --from=builder /opt/software /opt/software
    COPY --from=builder /opt/view /opt/view
    COPY --from=builder /etc/profile.d/z10_spack_environment.sh /etc/profile.d/z10_spack_environment.sh
 
-   RUN yum update -y && yum install -y epel-release && yum update -y                                   \
-    && yum install -y libgomp \
-    && rm -rf /var/cache/yum  && yum clean all
-
-   RUN echo 'export PS1="\[$(tput bold)\]\[$(tput setaf 1)\][gromacs]\[$(tput setaf 2)\]\u\[$(tput sgr0)\]:\w $ \[$(tput sgr0)\]"' >> ~/.bashrc
-
-
-   LABEL "app"="gromacs"
-   LABEL "mpi"="mpich"
-
    ENTRYPOINT ["/bin/bash", "--rcfile", "/etc/profile", "-l"]
 
+The image itself can then be built and run in the usual way, with any of the
+tools suitable for the task. For instance, if we decided to use ``docker``:
 
-The bits that make this automation possible are discussed in details
-below. All the images generated in this way will be based on
-multi-stage builds with:
+.. code-block:: bash
 
-- A fat ``build`` stage containing common build tools and Spack itself
-- A minimal ``final`` stage containing only the software requested by the user
+   $ spack containerize > Dockerfile
+   $ docker build -t myimage .
+   [ ... ]
+   $ docker run -it myimage
 
------------------
-Spack Base Images
------------------
+The various components involved in the generation of the recipe and their
+configuration are discussed in details in the sections below.
+
+.. _container_spack_images:
+
+--------------------------
+Spack Images on Docker Hub
+--------------------------
 
 Docker images with Spack preinstalled and ready to be used are
 built on `Docker Hub <https://hub.docker.com/u/spack>`_
@@ -124,19 +140,20 @@ All the images are tagged with the corresponding release of Spack:
 with the exception of the ``latest`` tag that points to the HEAD
 of the ``develop`` branch. These images are available for anyone
 to use and take care of all the repetitive tasks that are necessary
-to setup Spack within a container. All the container recipes generated
-automatically by Spack use them as base images for their ``build`` stage.
+to setup Spack within a container. The container recipes generated
+by Spack use them as default base images for their ``build`` stage,
+even though handles to use custom base images provided by users are
+available to accommodate complex use cases.
 
-
--------------------------
-Environment Configuration
--------------------------
+---------------------------------
+Creating Images From Environments
+---------------------------------
 
 Any Spack Environment can be used for the automatic generation of container
 recipes. Sensible defaults are provided for things like the base image or the
-version of Spack used in the image. If a finer tuning is needed it can be
-obtained by adding the relevant metadata under the ``container`` attribute
-of environments:
+version of Spack used in the image.
+If a finer tuning is needed it can be obtained by adding the relevant metadata
+under the ``container`` attribute of environments:
 
 .. code-block:: yaml
 
@@ -150,9 +167,10 @@ of environments:
        # singularity or anything else that is currently supported
        format: docker
 
-       # Select from a valid list of images
-       base:
-         image: "centos:7"
+       # Sets the base images for the stages where Spack builds the
+       # software or where the software gets installed after being built..
+       images:
+         os: "centos:7"
          spack: develop
 
        # Whether or not to strip binaries
@@ -160,19 +178,223 @@ of environments:
 
        # Additional system packages that are needed at runtime
        os_packages:
-       - libgomp
+         final:
+         - libgomp
 
        # Extra instructions
        extra_instructions:
          final: |
-           RUN echo 'export PS1="\[$(tput bold)\]\[$(tput setaf 1)\][gromacs]\[$(tput setaf 2)\]\u\[$(tput sgr0)\]:\w $ \[$(tput sgr0)\]"' >> ~/.bashrc
+           RUN echo 'export PS1="\[$(tput bold)\]\[$(tput setaf 1)\][gromacs]\[$(tput setaf 2)\]\u\[$(tput sgr0)\]:\w $ "' >> ~/.bashrc
 
        # Labels for the image
        labels:
          app: "gromacs"
          mpi: "mpich"
 
-The tables below describe the configuration options that are currently supported:
+A detailed description of the options available can be found in the
+:ref:`container_config_options` section.
+
+-------------------
+Setting Base Images
+-------------------
+
+The ``images`` subsection is used to select both the image where
+Spack builds the software and the image where the built software
+is installed. This attribute can be set in two different ways and
+which one to use depends on the use case at hand.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Use Official Spack Images From Dockerhub
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+To generate a recipe that uses an official Docker image from the
+Spack organization to build the software and the corresponding official OS image
+to install the built software, all the user has to do is specify:
+
+1. An operating system under ``images:os``
+2. A Spack version under ``images:spack``
+
+Any combination of these two values that can be mapped to one of the images
+discussed in :ref:`container_spack_images` is allowed. For instance, the
+following ``spack.yaml``:
+
+.. code-block:: yaml
+
+   spack:
+     specs:
+     - gromacs+mpi
+     - mpich
+
+     container:
+       images:
+         os: centos/7
+         spack: 0.15.4
+
+uses ``spack/centos7:0.15.4``  and ``centos:7`` for the stages where the
+software is respectively built and installed:
+
+.. code-block:: docker
+
+   # Build stage with Spack pre-installed and ready to be used
+   FROM spack/centos7:0.15.4 as builder
+
+   # What we want to install and how we want to install it
+   # is specified in a manifest file (spack.yaml)
+   RUN mkdir /opt/spack-environment \
+   &&  (echo "spack:" \
+   &&   echo "  specs:" \
+   &&   echo "  - gromacs+mpi" \
+   &&   echo "  - mpich" \
+   &&   echo "  concretization: together" \
+   &&   echo "  config:" \
+   &&   echo "    install_tree: /opt/software" \
+   &&   echo "  view: /opt/view") > /opt/spack-environment/spack.yaml
+   [ ... ]
+   # Bare OS image to run the installed executables
+   FROM centos:7
+
+   COPY --from=builder /opt/spack-environment /opt/spack-environment
+   COPY --from=builder /opt/software /opt/software
+   COPY --from=builder /opt/view /opt/view
+   COPY --from=builder /etc/profile.d/z10_spack_environment.sh /etc/profile.d/z10_spack_environment.sh
+
+   ENTRYPOINT ["/bin/bash", "--rcfile", "/etc/profile", "-l"]
+
+This method of selecting base images is the simplest of the two, and we advise
+to use it whenever possible. There are cases though where using Spack official
+images is not enough to fit production needs. In these situations users can manually
+select which base image to start from in the recipe, as we'll see next.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Use Custom Images Provided by Users
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Consider, as an example, building a production grade image for a CUDA
+application. The best strategy would probably be to build on top of
+images provided by the vendor and regard CUDA as an external package.
+
+Spack doesn't currently provide an official image with CUDA configured
+this way, but users can build it on their own and then configure the
+environment to explicitly pull it. This requires users to:
+
+1. Specify the image used to build the software under ``images:build``
+2. Specify the image used to install the built software under ``images:final``
+
+A ``spack.yaml`` like the following:
+
+.. code-block:: yaml
+
+   spack:
+     specs:
+     - gromacs@2019.4+cuda build_type=Release
+     - mpich
+     - fftw precision=float
+     packages:
+       cuda:
+         buildable: False
+         externals:
+         - spec: cuda%gcc
+           prefix: /usr/local/cuda
+
+     container:
+       images:
+         build: custom/cuda-10.1-ubuntu18.04:latest
+         final: nvidia/cuda:10.1-base-ubuntu18.04
+
+produces, for instance, the following ``Dockerfile``:
+
+.. code-block:: docker
+
+   # Build stage with Spack pre-installed and ready to be used
+   FROM custom/cuda-10.1-ubuntu18.04:latest as builder
+
+   # What we want to install and how we want to install it
+   # is specified in a manifest file (spack.yaml)
+   RUN mkdir /opt/spack-environment \
+   &&  (echo "spack:" \
+   &&   echo "  specs:" \
+   &&   echo "  - gromacs@2019.4+cuda build_type=Release" \
+   &&   echo "  - mpich" \
+   &&   echo "  - fftw precision=float" \
+   &&   echo "  packages:" \
+   &&   echo "    cuda:" \
+   &&   echo "      buildable: false" \
+   &&   echo "      externals:" \
+   &&   echo "      - spec: cuda%gcc" \
+   &&   echo "        prefix: /usr/local/cuda" \
+   &&   echo "  concretization: together" \
+   &&   echo "  config:" \
+   &&   echo "    install_tree: /opt/software" \
+   &&   echo "  view: /opt/view") > /opt/spack-environment/spack.yaml
+
+   # Install the software, remove unnecessary deps
+   RUN cd /opt/spack-environment && spack env activate . && spack install --fail-fast && spack gc -y
+
+   # Strip all the binaries
+   RUN find -L /opt/view/* -type f -exec readlink -f '{}' \; | \
+       xargs file -i | \
+       grep 'charset=binary' | \
+       grep 'x-executable\|x-archive\|x-sharedlib' | \
+       awk -F: '{print $1}' | xargs strip -s
+
+   # Modifications to the environment that are necessary to run
+   RUN cd /opt/spack-environment && \
+       spack env activate --sh -d . >> /etc/profile.d/z10_spack_environment.sh
+
+   # Bare OS image to run the installed executables
+   FROM nvidia/cuda:10.1-base-ubuntu18.04
+
+   COPY --from=builder /opt/spack-environment /opt/spack-environment
+   COPY --from=builder /opt/software /opt/software
+   COPY --from=builder /opt/view /opt/view
+   COPY --from=builder /etc/profile.d/z10_spack_environment.sh /etc/profile.d/z10_spack_environment.sh
+
+   ENTRYPOINT ["/bin/bash", "--rcfile", "/etc/profile", "-l"]
+
+where the base images for both stages are completely custom.
+
+This second mode of selection for base images is more flexible than just
+choosing an operating system and a Spack version, but is also more demanding.
+Users may need to generate by themselves their base images and it's also their
+responsibility to ensure that:
+
+1. Spack is available in the ``build`` stage and set up correctly to install the required software
+2. The artifacts produced in the ``build`` stage can be executed in the ``final`` stage
+
+Therefore we don't recommend its use in cases that can be otherwise
+covered by the simplified mode shown first.
+
+----------------------------
+Singularity Definition Files
+----------------------------
+
+In addition to producing recipes in ``Dockerfile`` format Spack can produce
+Singularity Definition Files by just changing the value of the ``format``
+attribute:
+
+.. code-block:: console
+
+   $ cat spack.yaml
+   spack:
+     specs:
+     - hdf5~mpi
+     container:
+       format: singularity
+
+   $ spack containerize > hdf5.def
+   $ sudo singularity build hdf5.sif hdf5.def
+
+The minimum version of Singularity required to build a SIF (Singularity Image Format)
+image from the recipes generated by Spack is ``3.5.3``.
+
+.. _container_config_options:
+
+-----------------------
+Configuration Reference
+-----------------------
+
+The tables below describe all the configuration options that are currently supported
+to customize the generation of container recipes:
 
 .. list-table:: General configuration options for the ``container`` section of ``spack.yaml``
    :header-rows: 1
@@ -185,21 +407,41 @@ The tables below describe the configuration options that are currently supported
      - The format of the recipe
      - ``docker`` or ``singularity``
      - Yes
-   * - ``base:image``
-     - Base image for ``final`` stage
+   * - ``images:os``
+     - Operating system used as a base for the image
      - See :ref:`containers-supported-os`
-     - Yes
-   * - ``base:spack``
-     - Version of Spack
+     - Yes, if using constrained selection of base images
+   * - ``images:spack``
+     - Version of Spack use in the ``build`` stage
      - Valid tags for ``base:image``
-     - Yes
+     - Yes, if using constrained selection of base images
+   * - ``images:build``
+     - Image to be used in the ``build`` stage
+     - Any valid container image
+     - Yes, if using custom selection of base images
+   * - ``images:final``
+     - Image to be used in the ``build`` stage
+     - Any valid container image
+     - Yes, if using custom selection of base images
    * - ``strip``
      - Whether to strip binaries
      - ``true`` (default) or ``false``
      - No
-   * - ``os_packages``
-     - System packages to be installed
-     - Valid packages for the ``final`` OS
+   * - ``os_packages:command``
+     - Tool used to manage system packages
+     - ``apt``, ``yum``
+     - Only with custom base images
+   * - ``os_packages:update``
+     - Whether or not to update the list of available packages
+     - True or False (default: True)
+     - No
+   * - ``os_packages:build``
+     - System packages needed at build-time
+     - Valid packages for the current OS
+     - No
+   * - ``os_packages:final``
+     - System packages needed at run-time
+     - Valid packages for the current OS
      - No
    * - ``extra_instructions:build``
      - Extra instructions (e.g. `RUN`, `COPY`, etc.) at the end of the ``build`` stage
@@ -238,70 +480,56 @@ The tables below describe the configuration options that are currently supported
      - Description string
      - No
 
-Once the Environment is properly configured a recipe for a container
-image can be printed to standard output by issuing the following
-command from the directory where the ``spack.yaml`` resides:
+--------------
+Best Practices
+--------------
 
-.. code-block:: console
+^^^
+MPI
+^^^
+Due to the dependency on Fortran for OpenMPI, which is the spack default
+implementation, consider adding ``gfortran`` to the ``apt-get install`` list.
 
-   $ spack containerize
+Recent versions of OpenMPI will require you to pass ``--allow-run-as-root``
+to your ``mpirun`` calls if started as root user inside Docker.
 
-The example ``spack.yaml`` above would produce for instance the
-following ``Dockerfile``:
+For execution on HPC clusters, it can be helpful to import the docker
+image into Singularity in order to start a program with an *external*
+MPI. Otherwise, also add ``openssh-server`` to the ``apt-get install`` list.
 
-.. code-block:: docker
+^^^^
+CUDA
+^^^^
+Starting from CUDA 9.0, Nvidia provides minimal CUDA images based on
+Ubuntu. Please see `their instructions <https://hub.docker.com/r/nvidia/cuda/>`_.
+Avoid double-installing CUDA by adding, e.g.
 
-   # Build stage with Spack pre-installed and ready to be used
-   FROM spack/centos7:latest as builder
+.. code-block:: yaml
 
-   # What we want to install and how we want to install it
-   # is specified in a manifest file (spack.yaml)
-   RUN mkdir /opt/spack-environment \
-   &&  (echo "spack:" \
-   &&   echo "  specs:" \
-   &&   echo "  - gromacs+mpi" \
-   &&   echo "  - mpich" \
-   &&   echo "  concretization: together" \
-   &&   echo "  config:" \
-   &&   echo "    install_tree: /opt/software" \
-   &&   echo "  view: /opt/view") > /opt/spack-environment/spack.yaml
+   packages:
+     cuda:
+       externals:
+       - spec: "cuda@9.0.176%gcc@5.4.0 arch=linux-ubuntu16-x86_64"
+         prefix: /usr/local/cuda
+       buildable: False
 
-   # Install the software, remove unnecessary deps
-   RUN cd /opt/spack-environment && spack install && spack gc -y
+to your ``spack.yaml``.
 
-   # Strip all the binaries
-   RUN find -L /opt/view/* -type f -exec readlink -f '{}' \; | \
-       xargs file -i | \
-       grep 'charset=binary' | \
-       grep 'x-executable\|x-archive\|x-sharedlib' | \
-       awk -F: '{print $1}' | xargs strip -s
+Users will either need ``nvidia-docker`` or e.g. Singularity to *execute*
+device kernels.
 
-   # Modifications to the environment that are necessary to run
-   RUN cd /opt/spack-environment && \
-       spack env activate --sh -d . >> /etc/profile.d/z10_spack_environment.sh
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Docker on Windows and OSX
+^^^^^^^^^^^^^^^^^^^^^^^^^
 
+On Mac OS and Windows, docker runs on a hypervisor that is not allocated much
+memory by default, and some spack packages may fail to build due to lack of
+memory. To work around this issue, consider configuring your docker installation
+to use more of your host memory. In some cases, you can also ease the memory
+pressure on parallel builds by limiting the parallelism in your config.yaml.
 
-   # Bare OS image to run the installed executables
-   FROM centos:7
+.. code-block:: yaml
 
-   COPY --from=builder /opt/spack-environment /opt/spack-environment
-   COPY --from=builder /opt/software /opt/software
-   COPY --from=builder /opt/view /opt/view
-   COPY --from=builder /etc/profile.d/z10_spack_environment.sh /etc/profile.d/z10_spack_environment.sh
+   config:
+     build_jobs: 2
 
-   RUN yum update -y && yum install -y epel-release && yum update -y                                   \
-    && yum install -y libgomp \
-    && rm -rf /var/cache/yum  && yum clean all
-
-   RUN echo 'export PS1="\[$(tput bold)\]\[$(tput setaf 1)\][gromacs]\[$(tput setaf 2)\]\u\[$(tput sgr0)\]:\w $ \[$(tput sgr0)\]"' >> ~/.bashrc
-
-
-   LABEL "app"="gromacs"
-   LABEL "mpi"="mpich"
-
-   ENTRYPOINT ["/bin/bash", "--rcfile", "/etc/profile", "-l"]
-
-.. note::
-   Spack can also produce Singularity definition files to build the image. The
-   minimum version of Singularity required to build a SIF (Singularity Image Format)
-   from them is ``3.5.3``.

lib/spack/docs/contribution_guide.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -27,17 +27,28 @@ correspond to one feature/bugfix/extension/etc. One can create PRs with
 changes relevant to different ideas, however reviewing such PRs becomes tedious
 and error prone. If possible, try to follow the **one-PR-one-package/feature** rule.
 
-Spack uses a rough approximation of the `Git Flow <http://nvie.com/posts/a-successful-git-branching-model/>`_
-branching model. The develop branch contains the latest contributions, and
-master is always tagged and points to the latest stable release. Therefore, when
-you send your request, make ``develop`` the destination branch on the
-`Spack repository <https://github.com/spack/spack>`_.
+--------
+Branches
+--------
+
+Spack's ``develop`` branch has the latest contributions. Nearly all pull
+requests should start from ``develop`` and target ``develop``.
+
+There is a branch for each major release series. Release branches
+originate from ``develop`` and have tags for each point release in the
+series. For example, ``releases/v0.14`` has tags for ``0.14.0``,
+``0.14.1``, ``0.14.2``, etc. versions of Spack. We backport important bug
+fixes to these branches, but we do not advance the package versions or
+make other changes that would change the way Spack concretizes
+dependencies. Currently, the maintainers manage these branches by
+cherry-picking from ``develop``. See :ref:`releases` for more
+information.
 
 ----------------------
 Continuous Integration
 ----------------------
 
-Spack uses `Travis CI <https://travis-ci.org/spack/spack>`_ for Continuous Integration
+Spack uses `Github Actions <https://docs.github.com/en/actions>`_ for Continuous Integration
 testing. This means that every time you submit a pull request, a series of tests will
 be run to make sure you didn't accidentally introduce any bugs into Spack. **Your PR
 will not be accepted until it passes all of these tests.** While you can certainly wait
@@ -46,25 +57,24 @@ locally to speed up the review process.
 
 .. note::
 
-   Oftentimes, Travis will fail for reasons other than a problem with your PR.
+   Oftentimes, CI will fail for reasons other than a problem with your PR.
    For example, apt-get, pip, or homebrew will fail to download one of the
    dependencies for the test suite, or a transient bug will cause the unit tests
-   to timeout. If Travis fails, click the "Details" link and click on the test(s)
+   to timeout. If any job fails, click the "Details" link and click on the test(s)
    that is failing. If it doesn't look like it is failing for reasons related to
    your PR, you have two options. If you have write permissions for the Spack
-   repository, you should see a "Restart job" button on the right-hand side. If
+   repository, you should see a "Restart workflow" button on the right-hand side. If
    not, you can close and reopen your PR to rerun all of the tests. If the same
    test keeps failing, there may be a problem with your PR. If you notice that
-   every recent PR is failing with the same error message, it may be that Travis
-   is down or one of Spack's dependencies put out a new release that is causing
-   problems. If this is the case, please file an issue.
+   every recent PR is failing with the same error message, it may be that an issue
+   occurred with the CI infrastructure or one of Spack's dependencies put out a
+   new release that is causing problems. If this is the case, please file an issue.
 
 
-If you take a look in ``$SPACK_ROOT/.travis.yml``, you'll notice that we test
-against Python 2.6, 2.7, and 3.4-3.7 on both macOS and Linux. We currently
+We currently test against Python 2.6, 2.7, and 3.5-3.7 on both macOS and Linux and
 perform 3 types of tests:
 
-.. _cmd-spack-test:
+.. _cmd-spack-unit-test:
 
 ^^^^^^^^^^
 Unit Tests
@@ -86,7 +96,7 @@ To run *all* of the unit tests, use:
 
 .. code-block:: console
 
-   $ spack test
+   $ spack unit-test
 
 These tests may take several minutes to complete. If you know you are
 only modifying a single Spack feature, you can run subsets of tests at a
@@ -95,51 +105,53 @@ time.  For example, this would run all the tests in
 
 .. code-block:: console
 
-   $ spack test architecture.py
+   $ spack unit-test lib/spack/spack/test/architecture.py
 
 And this would run the ``test_platform`` test from that file:
 
 .. code-block:: console
 
-   $ spack test architecture.py::test_platform
+   $ spack unit-test lib/spack/spack/test/architecture.py::test_platform
 
 This allows you to develop iteratively: make a change, test that change,
 make another change, test that change, etc.  We use `pytest
-<http://pytest.org/>`_ as our tests fromework, and these types of
+<http://pytest.org/>`_ as our tests framework, and these types of
 arguments are just passed to the ``pytest`` command underneath. See `the
 pytest docs
 <http://doc.pytest.org/en/latest/usage.html#specifying-tests-selecting-tests>`_
 for more details on test selection syntax.
 
-``spack test`` has a few special options that can help you understand
-what tests are available.  To get a list of all available unit test
-files, run:
+``spack unit-test`` has a few special options that can help you
+understand what tests are available.  To get a list of all available
+unit test files, run:
 
-.. command-output:: spack test --list
+.. command-output:: spack unit-test --list
    :ellipsis: 5
 
-To see a more detailed list of available unit tests, use ``spack test
---list-long``:
+To see a more detailed list of available unit tests, use ``spack
+unit-test --list-long``:
 
-.. command-output:: spack test --list-long
+.. command-output:: spack unit-test --list-long
    :ellipsis: 10
 
 And to see the fully qualified names of all tests, use ``--list-names``:
 
-.. command-output:: spack test --list-names
+.. command-output:: spack unit-test --list-names
    :ellipsis: 5
 
 You can combine these with ``pytest`` arguments to restrict which tests
 you want to know about.  For example, to see just the tests in
 ``architecture.py``:
 
-.. command-output:: spack test --list-long architecture.py
+.. command-output:: spack unit-test --list-long lib/spack/spack/test/architecture.py
 
 You can also combine any of these options with a ``pytest`` keyword
-search.  For example, to see the names of all tests that have "spec"
+search.  See the `pytest usage docs
+<https://docs.pytest.org/en/stable/usage.html#specifying-tests-selecting-tests>`_:
+for more details on test selection syntax. For example, to see the names of all tests that have "spec"
 or "concretize" somewhere in their names:
 
-.. command-output:: spack test --list-names -k "spec and concretize"
+.. command-output:: spack unit-test --list-names -k "spec and concretize"
 
 By default, ``pytest`` captures the output of all unit tests, and it will
 print any captured output for failed tests. Sometimes it's helpful to see
@@ -149,7 +161,7 @@ argument to ``pytest``:
 
 .. code-block:: console
 
-   $ spack test -s architecture.py::test_platform
+   $ spack unit-test -s --list-long lib/spack/spack/test/architecture.py::test_platform
 
 Unit tests are crucial to making sure bugs aren't introduced into
 Spack. If you are modifying core Spack libraries or adding new
@@ -162,29 +174,31 @@ how to write tests!
 .. note::
 
    You may notice the ``share/spack/qa/run-unit-tests`` script in the
-   repository.  This script is designed for Travis CI.  It runs the unit
+   repository.  This script is designed for CI.  It runs the unit
    tests and reports coverage statistics back to Codecov. If you want to
-   run the unit tests yourself, we suggest you use ``spack test``.
+   run the unit tests yourself, we suggest you use ``spack unit-test``.
 
 ^^^^^^^^^^^^
-Flake8 Tests
+Style Tests
 ^^^^^^^^^^^^
 
 Spack uses `Flake8 <http://flake8.pycqa.org/en/latest/>`_ to test for
-`PEP 8 <https://www.python.org/dev/peps/pep-0008/>`_ conformance. PEP 8 is
+`PEP 8 <https://www.python.org/dev/peps/pep-0008/>`_ conformance and
+`mypy <https://mypy.readthedocs.io/en/stable/>` for type checking. PEP 8 is
 a series of style guides for Python that provide suggestions for everything
 from variable naming to indentation. In order to limit the number of PRs that
 were mostly style changes, we decided to enforce PEP 8 conformance. Your PR
-needs to comply with PEP 8 in order to be accepted.
+needs to comply with PEP 8 in order to be accepted, and if it modifies the
+spack library it needs to successfully type-check with mypy as well.
 
-Testing for PEP 8 compliance is easy. Simply run the ``spack flake8``
+Testing for compliance with spack's style is easy. Simply run the ``spack style``
 command:
 
 .. code-block:: console
 
-   $ spack flake8
+   $ spack style
 
-``spack flake8`` has a couple advantages over running ``flake8`` by hand:
+``spack style`` has a couple advantages over running the tools by hand:
 
 #. It only tests files that you have modified since branching off of
    ``develop``.
@@ -195,7 +209,9 @@ command:
    checks. For example, URLs are often longer than 80 characters, so we
    exempt them from line length checks. We also exempt lines that start
    with "homepage", "url", "version", "variant", "depends_on", and
-   "extends" in ``package.py`` files.
+   "extends" in ``package.py`` files.  This is now also possible when directly
+   running flake8 if you can use the ``spack`` formatter plugin included with
+   spack.
 
 More approved flake8 exemptions can be found
 `here <https://github.com/spack/spack/blob/develop/.flake8>`_.
@@ -228,14 +244,14 @@ However, if you aren't compliant with PEP 8, flake8 will complain:
 
 Most of the error messages are straightforward, but if you don't understand what
 they mean, just ask questions about them when you submit your PR. The line numbers
-will change if you add or delete lines, so simply run ``spack flake8`` again
+will change if you add or delete lines, so simply run ``spack style`` again
 to update them.
 
 .. tip::
 
    Try fixing flake8 errors in reverse order. This eliminates the need for
-   multiple runs of ``spack flake8`` just to re-compute line numbers and
-   makes it much easier to fix errors directly off of the Travis output.
+   multiple runs of ``spack style`` just to re-compute line numbers and
+   makes it much easier to fix errors directly off of the CI output.
 
 .. warning::
 
@@ -315,7 +331,7 @@ Once all of the dependencies are installed, you can try building the documentati
 
 .. code-block:: console
 
-   $ cd "$SPACK_ROOT/lib/spack/docs"
+   $ cd path/to/spack/lib/spack/docs/
    $ make clean
    $ make
 
@@ -327,7 +343,7 @@ your PR is accepted.
    There is also a ``run-doc-tests`` script in ``share/spack/qa``. The only
    difference between running this script and running ``make`` by hand is that
    the script will exit immediately if it encounters an error or warning. This
-   is necessary for Travis CI. If you made a lot of documentation changes, it is
+   is necessary for CI. If you made a lot of documentation changes, it is
    much quicker to run ``make`` by hand so that you can see all of the warnings
    at once.
 
@@ -391,7 +407,7 @@ and allow you to see coverage line-by-line when viewing the Spack repository.
 If you are new to Spack, a great way to get started is to write unit tests to
 increase coverage!
 
-Unlike with Travis, Codecov tests are not required to pass in order for your
+Unlike with CI on Github Actions Codecov tests are not required to pass in order for your
 PR to be merged. If you modify core Spack libraries, we would greatly
 appreciate unit tests that cover these changed lines. Otherwise, we have no
 way of knowing whether or not your changes introduce a bug. If you make

lib/spack/docs/developer_guide.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -363,11 +363,12 @@ Developer commands
 ``spack doc``
 ^^^^^^^^^^^^^
 
-^^^^^^^^^^^^^^
-``spack test``
-^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^^^^^
+``spack unit-test``
+^^^^^^^^^^^^^^^^^^^
 
-See the :ref:`contributor guide section <cmd-spack-test>` on ``spack test``.
+See the :ref:`contributor guide section <cmd-spack-unit-test>` on
+``spack unit-test``.
 
 .. _cmd-spack-python:
 
@@ -395,20 +396,42 @@ other Spack modules:
    True
    >>>
 
-You can also run a single command:
+If you prefer using an IPython interpreter, given that IPython is installed
+you can specify the interpreter with ``-i``:
+
+.. code-block:: console
+
+   $ spack python -i ipython
+   Python 3.8.3 (default, May 19 2020, 18:47:26) 
+   Type 'copyright', 'credits' or 'license' for more information
+   IPython 7.17.0 -- An enhanced Interactive Python. Type '?' for help.
+
+
+   Spack version 0.16.0
+   Python 3.8.3, Linux x86_64
+
+   In [1]:
+
+
+With either interpreter you can run a single command:
 
 .. code-block:: console
 
    $ spack python -c 'import distro; distro.linux_distribution()'
-   ('Fedora', '25', 'Workstation Edition')
+   ('Ubuntu', '18.04', 'Bionic Beaver')
+
+   $ spack python -i ipython -c 'import distro; distro.linux_distribution()'
+   Out[1]: ('Ubuntu', '18.04', 'Bionic Beaver')
 
 or a file:
 
 .. code-block:: console
 
    $ spack python ~/test_fetching.py
+   $ spack python -i ipython ~/test_fetching.py
+
+just like you would with the normal ``python`` command. 
 
-just like you would with the normal ``python`` command.
 
 .. _cmd-spack-url:
 
@@ -495,3 +518,384 @@ The bottom of the output shows the top most time consuming functions,
 slowest on top.  The profiling support is from Python's built-in tool,
 `cProfile
 <https://docs.python.org/2/library/profile.html#module-cProfile>`_.
+
+.. _releases:
+
+--------
+Releases
+--------
+
+This section documents Spack's release process. It is intended for
+project maintainers, as the tasks described here require maintainer
+privileges on the Spack repository. For others, we hope this section at
+least provides some insight into how the Spack project works.
+
+.. _release-branches:
+
+^^^^^^^^^^^^^^^^
+Release branches
+^^^^^^^^^^^^^^^^
+
+There are currently two types of Spack releases: :ref:`major releases
+<major-releases>` (``0.13.0``, ``0.14.0``, etc.) and :ref:`point releases
+<point-releases>` (``0.13.1``, ``0.13.2``, ``0.13.3``, etc.). Here is a
+diagram of how Spack release branches work::
+
+    o    branch: develop  (latest version)
+    |
+    o    merge v0.14.1 into develop
+    |\
+    | o  branch: releases/v0.14, tag: v0.14.1
+    o |  merge v0.14.0 into develop
+    |\|
+    | o  tag: v0.14.0
+    |/
+    o    merge v0.13.2 into develop
+    |\
+    | o  branch: releases/v0.13, tag: v0.13.2
+    o |  merge v0.13.1 into develop
+    |\|
+    | o  tag: v0.13.1
+    o |  merge v0.13.0 into develop
+    |\|
+    | o  tag: v0.13.0
+    o |
+    | o
+    |/
+    o
+
+The ``develop`` branch has the latest contributions, and nearly all pull
+requests target ``develop``.
+
+Each Spack release series also has a corresponding branch, e.g.
+``releases/v0.14`` has ``0.14.x`` versions of Spack, and
+``releases/v0.13`` has ``0.13.x`` versions. A major release is the first
+tagged version on a release branch. Minor releases are back-ported from
+develop onto release branches. This is typically done by cherry-picking
+bugfix commits off of ``develop``.
+
+To avoid version churn for users of a release series, minor releases
+should **not** make changes that would change the concretization of
+packages. They should generally only contain fixes to the Spack core.
+
+Both major and minor releases are tagged. After each release, we merge
+the release branch back into ``develop`` so that the version bump and any
+other release-specific changes are visible in the mainline. As a
+convenience, we also tag the latest release as ``releases/latest``,
+so that users can easily check it out to get the latest
+stable version. See :ref:`merging-releases` for more details.
+
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Scheduling work for releases
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+We schedule work for releases by creating `GitHub projects
+<https://github.com/spack/spack/projects>`_. At any time, there may be
+several open release projects. For example, here are two releases (from
+some past version of the page linked above):
+
+.. image:: images/projects.png
+
+Here, there's one release in progress for ``0.15.1`` and another for
+``0.16.0``. Each of these releases has a project board containing issues
+and pull requests. GitHub shows a status bar with completed work in
+green, work in progress in purple, and work not started yet in gray, so
+it's fairly easy to see progress.
+
+Spack's project boards are not firm commitments, and we move work between
+releases frequently. If we need to make a release and some tasks are not
+yet done, we will simply move them to next minor or major release, rather
+than delaying the release to complete them.
+
+For more on using GitHub project boards, see `GitHub's documentation
+<https://docs.github.com/en/github/managing-your-work-on-github/about-project-boards>`_.
+
+.. _major-releases:
+
+^^^^^^^^^^^^^^^^^^^^^
+Making Major Releases
+^^^^^^^^^^^^^^^^^^^^^
+
+Assuming you've already created a project board and completed the work
+for a major release, the steps to make the release are as follows:
+
+#. Create two new project boards:
+
+   * One for the next major release
+   * One for the next point release
+
+#. Move any tasks that aren't done yet to one of the new project boards.
+   Small bugfixes should go to the next point release. Major features,
+   refactors, and changes that could affect concretization should go in
+   the next major release.
+
+#. Create a branch for the release, based on ``develop``:
+
+   .. code-block:: console
+
+      $ git checkout -b releases/v0.15 develop
+
+   For a version ``vX.Y.Z``, the branch's name should be
+   ``releases/vX.Y``. That is, you should create a ``releases/vX.Y``
+   branch if you are preparing the ``X.Y.0`` release.
+
+#. Bump the version in ``lib/spack/spack/__init__.py``. See `this example from 0.13.0
+   <https://github.com/spack/spack/commit/8eeb64096c98b8a43d1c587f13ece743c864fba9>`_
+
+#. Update ``CHANGELOG.md`` with major highlights in bullet form. Use
+   proper markdown formatting, like `this example from 0.15.0
+   <https://github.com/spack/spack/commit/d4bf70d9882fcfe88507e9cb444331d7dd7ba71c>`_.
+
+#. Push the release branch to GitHub.
+
+#. Make sure CI passes on the release branch, including:
+
+   * Regular unit tests
+   * Build tests
+   * The E4S pipeline at `gitlab.spack.io <https://gitlab.spack.io>`_
+
+   If CI is not passing, submit pull requests to ``develop`` as normal
+   and keep rebasing the release branch on ``develop`` until CI passes.
+
+#. Follow the steps in :ref:`publishing-releases`.
+
+#. Follow the steps in :ref:`merging-releases`.
+
+#. Follow the steps in :ref:`announcing-releases`.
+
+
+.. _point-releases:
+
+^^^^^^^^^^^^^^^^^^^^^
+Making Point Releases
+^^^^^^^^^^^^^^^^^^^^^
+
+This assumes you've already created a project board for a point release
+and completed the work to be done for the release. To make a point
+release:
+
+#. Create one new project board for the next point release.
+
+#. Move any cards that aren't done yet to the next project board.
+
+#. Check out the release branch (it should already exist). For the
+   ``X.Y.Z`` release, the release branch is called ``releases/vX.Y``. For
+   ``v0.15.1``, you would check out ``releases/v0.15``:
+
+   .. code-block:: console
+
+      $ git checkout releases/v0.15
+
+#. Cherry-pick each pull request in the ``Done`` column of the release
+   project onto the release branch.
+
+   This is **usually** fairly simple since we squash the commits from the
+   vast majority of pull requests, which means there is only one commit
+   per pull request to cherry-pick. For example, `this pull request
+   <https://github.com/spack/spack/pull/15777>`_ has three commits, but
+   the were squashed into a single commit on merge. You can see the
+   commit that was created here:
+
+   .. image:: images/pr-commit.png
+
+   You can easily cherry pick it like this (assuming you already have the
+   release branch checked out):
+
+   .. code-block:: console
+
+      $ git cherry-pick 7e46da7
+
+   For pull requests that were rebased, you'll need to cherry-pick each
+   rebased commit individually. There have not been any rebased PRs like
+   this in recent point releases.
+
+   .. warning::
+
+      It is important to cherry-pick commits in the order they happened,
+      otherwise you can get conflicts while cherry-picking. When
+      cherry-picking onto a point release, look at the merge date,
+      **not** the number of the pull request or the date it was opened.
+
+      Sometimes you may **still** get merge conflicts even if you have
+      cherry-picked all the commits in order. This generally means there
+      is some other intervening pull request that the one you're trying
+      to pick depends on. In these cases, you'll need to make a judgment
+      call:
+
+      1. If the dependency is small, you might just cherry-pick it, too.
+         If you do this, add it to the release board.
+
+      2. If it is large, then you may decide that this fix is not worth
+         including in a point release, in which case you should remove it
+         from the release project.
+
+      3. You can always decide to manually back-port the fix to the release
+         branch if neither of the above options makes sense, but this can
+         require a lot of work. It's seldom the right choice.
+
+#. Bump the version in ``lib/spack/spack/__init__.py``. See `this example from 0.14.1
+   <https://github.com/spack/spack/commit/ff0abb9838121522321df2a054d18e54b566b44a>`_.
+
+#. Update ``CHANGELOG.md`` with a list of bugfixes. This is typically just a
+   summary of the commits you cherry-picked onto the release branch. See
+   `the changelog from 0.14.1
+   <https://github.com/spack/spack/commit/ff0abb9838121522321df2a054d18e54b566b44a>`_.
+
+#. Push the release branch to GitHub.
+
+#. Make sure CI passes on the release branch, including:
+   * Regular unit tests
+   * Build tests
+   * The E4S pipeline at `gitlab.spack.io <https://gitlab.spack.io>`_
+
+   If CI does not pass, you'll need to figure out why, and make changes
+   to the release branch until it does. You can make more commits, modify
+   or remove cherry-picked commits, or cherry-pick **more** from
+   ``develop`` to make this happen.
+
+#. Follow the steps in :ref:`publishing-releases`.
+
+#. Follow the steps in :ref:`merging-releases`.
+
+#. Follow the steps in :ref:`announcing-releases`.
+
+
+.. _publishing-releases:
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Publishing a release on GitHub
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+#. Go to `github.com/spack/spack/releases
+   <https://github.com/spack/spack/releases>`_ and click ``Draft a new
+   release``.  Set the following:
+
+   * ``Tag version`` should start with ``v`` and contain *all three*
+     parts of the version, .g. ``v0.15.1``. This is the name of the tag
+     that will be created.
+
+   * ``Target`` should be the ``releases/vX.Y`` branch (e.g., ``releases/v0.15``).
+
+   * ``Release title`` should be ``vX.Y.Z`` (To match the tag, e.g., ``v0.15.1``).
+
+   * For the text, paste the latest release markdown from your ``CHANGELOG.md``.
+
+   You can save the draft and keep coming back to this as you prepare the release.
+
+#. When you are done, click ``Publish release``.
+
+#. Immediately after publishing, go back to
+   `github.com/spack/spack/releases
+   <https://github.com/spack/spack/releases>`_ and download the
+   auto-generated ``.tar.gz`` file for the release. It's the ``Source
+   code (tar.gz)`` link.
+
+#. Click ``Edit`` on the release you just did and attach the downloaded
+   release tarball as a binary. This does two things:
+
+   #. Makes sure that the hash of our releases doesn't change over time.
+      GitHub sometimes annoyingly changes they way they generate
+      tarballs, and then hashes can change if you rely on the
+      auto-generated tarball links.
+
+   #. Gets us download counts on releases visible through the GitHub
+      API. GitHub tracks downloads of artifacts, but *not* the source
+      links. See the `releases
+      page <https://api.github.com/repos/spack/spack/releases>`_ and search
+      for ``download_count`` to see this.
+
+#. Go to `readthedocs.org <https://readthedocs.org/projects/spack>`_ and activate
+   the release tag. This builds the documentation and makes the released version
+   selectable in the versions menu.
+
+
+.. _merging-releases:
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Updating `releases/latest` and `develop`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If the new release is the **highest** Spack release yet, you should
+also tag it as ``releases/latest``. For example, suppose the highest
+release is currently ``0.15.3``:
+
+     * If you are releasing ``0.15.4`` or ``0.16.0``, then you should tag
+       it with ``releases/latest``, as these are higher than ``0.15.3``.
+
+     * If you are making a new release of an **older** major version of
+       Spack, e.g. ``0.14.4``, then you should not tag it as
+       ``releases/latest`` (as there are newer major versions).
+
+   To tag ``releases/latest``, do this:
+
+   .. code-block:: console
+
+      $ git checkout releases/vX.Y     # vX.Y is the new release's branch
+      $ git tag --force releases/latest
+      $ git push --tags
+
+   The ``--force`` argument makes ``git`` overwrite the existing
+   ``releases/latest`` tag with the new one.
+
+We also merge each release that we tag as ``releases/latest`` into ``develop``.
+Make sure to do this with a merge commit:
+
+.. code-block:: console
+
+   $ git checkout develop
+   $ git merge --no-ff vX.Y.Z  # vX.Y.Z is the new release's tag
+   $ git push
+
+We merge back to ``develop`` because it:
+
+  * updates the version and ``CHANGELOG.md`` on ``develop``.
+  * ensures that your release tag is reachable from the head of
+    ``develop``
+
+We *must* use a real merge commit (via the ``--no-ff`` option) because it
+ensures that the release tag is reachable from the tip of ``develop``.
+This is necessary for ``spack -V`` to work properly -- it uses ``git
+describe --tags`` to find the last reachable tag in the repository and
+reports how far we are from it. For example:
+
+.. code-block:: console
+
+   $ spack -V
+   0.14.2-1486-b80d5e74e5
+
+This says that we are at commit ``b80d5e74e5``, which is 1,486 commits
+ahead of the ``0.14.2`` release.
+
+We put this step last in the process because it's best to do it only once
+the release is complete and tagged. If you do it before you've tagged the
+release and later decide you want to tag some later commit, you'll need
+to merge again.
+
+.. _announcing-releases:
+
+^^^^^^^^^^^^^^^^^^^^
+Announcing a release
+^^^^^^^^^^^^^^^^^^^^
+
+We announce releases in all of the major Spack communication channels.
+Publishing the release takes care of GitHub. The remaining channels are
+Twitter, Slack, and the mailing list. Here are the steps:
+
+#. Make a tweet to announce the release. It should link to the release's
+   page on GitHub. You can base it on `this example tweet
+   <https://twitter.com/spackpm/status/1231761858182307840>`_.
+
+#. Ping ``@channel`` in ``#general`` on Slack (`spackpm.slack.com
+   <https://spackpm.slack.com>`_) with a link to the tweet. The tweet
+   will be shown inline so that you do not have to retype your release
+   announcement.
+
+#. Email the Spack mailing list to let them know about the release. As
+   with the tweet, you likely want to link to the release's page on
+   GitHub. It's also helpful to include some information directly in the
+   email. You can base yours on this `example email
+   <https://groups.google.com/forum/#!topic/spack/WT4CT9i_X4s>`_.
+
+Once you've announced the release, congratulations, you're done! You've
+finished making the release!

lib/spack/docs/docker_for_developers.rst

@@ -1,41 +0,0 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-   Spack Project Developers. See the top-level COPYRIGHT file for details.
-
-   SPDX-License-Identifier: (Apache-2.0 OR MIT)
-
-.. _docker_for_developers:
-
-=====================
-Docker for Developers
-=====================
-
-This guide is intended for people who want to use our prepared docker
-environments to work on developing Spack or working on spack packages. It is
-meant to serve as the companion documentation for the :ref:`packaging-guide`.
-
---------
-Overview
---------
-
-To get started, all you need is the latest version of ``docker``.
-
-.. code-block:: console
-
-    $ cd share/spack/docker
-    $ source config/ubuntu.bash
-    $ ./run-image.sh
-
-This command should drop you into an interactive shell where you can run spack
-within an isolated docker container running ubuntu.  The copy of spack being
-used should be tied to the working copy of your cloned git repo, so any changes
-you make should be immediately reflected in the running docker container.  Feel
-free to add or modify any packages or to hack on spack, itself.  Your contained
-copy of spack should immediately reflect all changes.
-
-To work within a container running a different linux distro, source one of the
-other environment files under ``config``.
-
-.. code-block:: console
-
-    $ source config/fedora.bash
-    $ ./run-image.sh

lib/spack/docs/environments.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -191,44 +191,24 @@ Environment has been activated. Similarly, the ``install`` and
   ==> 0 installed packages
 
   $ spack install zlib@1.2.11
-  ==> Installing zlib
-  ==> Searching for binary cache of zlib
-  ==> Warning: No Spack mirrors are currently configured
-  ==> No binary for zlib found: installing from source
-  ==> Fetching http://zlib.net/fossils/zlib-1.2.11.tar.gz
-  ######################################################################## 100.0%
-  ==> Staging archive: /spack/var/spack/stage/zlib-1.2.11-3r4cfkmx3wwfqeof4bc244yduu2mz4ur/zlib-1.2.11.tar.gz
-  ==> Created stage in /spack/var/spack/stage/zlib-1.2.11-3r4cfkmx3wwfqeof4bc244yduu2mz4ur
-  ==> No patches needed for zlib
-  ==> Building zlib [Package]
-  ==> Executing phase: 'install'
-  ==> Successfully installed zlib
-    Fetch: 0.36s.  Build: 11.58s.  Total: 11.93s.
-  [+] /spack/opt/spack/linux-rhel7-x86_64/gcc-4.9.3/zlib-1.2.11-3r4cfkmx3wwfqeof4bc244yduu2mz4ur
+  ==> Installing zlib-1.2.11-q6cqrdto4iktfg6qyqcc5u4vmfmwb7iv
+  ==> No binary for zlib-1.2.11-q6cqrdto4iktfg6qyqcc5u4vmfmwb7iv found: installing from source
+  ==> zlib: Executing phase: 'install'
+  [+] ~/spack/opt/spack/linux-rhel7-broadwell/gcc-8.1.0/zlib-1.2.11-q6cqrdto4iktfg6qyqcc5u4vmfmwb7iv
 
   $ spack env activate myenv
 
   $ spack find
   ==> In environment myenv
   ==> No root specs
-
   ==> 0 installed packages
 
   $ spack install zlib@1.2.8
-  ==> Installing zlib
-  ==> Searching for binary cache of zlib
-  ==> Warning: No Spack mirrors are currently configured
-  ==> No binary for zlib found: installing from source
-  ==> Fetching http://zlib.net/fossils/zlib-1.2.8.tar.gz
-  ######################################################################## 100.0%
-  ==> Staging archive: /spack/var/spack/stage/zlib-1.2.8-y2t6kq3s23l52yzhcyhbpovswajzi7f7/zlib-1.2.8.tar.gz
-  ==> Created stage in /spack/var/spack/stage/zlib-1.2.8-y2t6kq3s23l52yzhcyhbpovswajzi7f7
-  ==> No patches needed for zlib
-  ==> Building zlib [Package]
-  ==> Executing phase: 'install'
-  ==> Successfully installed zlib
-    Fetch: 0.26s.  Build: 2.08s.  Total: 2.35s.
-  [+] /spack/opt/spack/linux-rhel7-x86_64/gcc-4.9.3/zlib-1.2.8-y2t6kq3s23l52yzhcyhbpovswajzi7f7
+  ==> Installing zlib-1.2.8-yfc7epf57nsfn2gn4notccaiyxha6z7x
+  ==> No binary for zlib-1.2.8-yfc7epf57nsfn2gn4notccaiyxha6z7x found: installing from source
+  ==> zlib: Executing phase: 'install'
+  [+] ~/spack/opt/spack/linux-rhel7-broadwell/gcc-8.1.0/zlib-1.2.8-yfc7epf57nsfn2gn4notccaiyxha6z7x
+  ==> Updating view at ~/spack/var/spack/environments/myenv/.spack-env/view
 
   $ spack find
   ==> In environment myenv
@@ -236,15 +216,17 @@ Environment has been activated. Similarly, the ``install`` and
   zlib@1.2.8
 
   ==> 1 installed package
-  -- linux-rhel7-x86_64 / gcc@4.9.3 -------------------------------
+  -- linux-rhel7-broadwell / gcc@8.1.0 ----------------------------
   zlib@1.2.8
 
   $ despacktivate
+
   $ spack find
   ==> 2 installed packages
-  -- linux-rhel7-x86_64 / gcc@4.9.3 -------------------------------
+  -- linux-rhel7-broadwell / gcc@8.1.0 ----------------------------
   zlib@1.2.8  zlib@1.2.11
 
+
 Note that when we installed the abstract spec ``zlib@1.2.8``, it was
 presented as a root of the Environment. All explicitly installed
 packages will be listed as roots of the Environment.
@@ -349,6 +331,9 @@ installed specs using the ``-c`` (``--concretized``) flag.
 
   ==> 0 installed packages
 
+
+.. _installing-environment:
+
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 Installing an Environment
 ^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -830,8 +815,10 @@ environment for Spack commands. The arguments ``-v,--with-view`` and
 behavior is to activate with the environment view if there is one.
 
 The environment variables affected by the ``spack env activate``
-command and the paths that are used to update them are in the
-following table.
+command and the paths that are used to update them are determined by
+the :ref:`prefix inspections <customize-env-modifications>` defined in
+your modules configuration; the defaults are summarized in the following
+table.
 
 =================== =========
 Variable            Paths

lib/spack/docs/extensions.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -87,11 +87,12 @@ will be available from the command line:
      --implicit       select specs that are not installed or were installed implicitly
      --output OUTPUT  where to dump the result
 
-The corresponding unit tests can be run giving the appropriate options to ``spack test``:
+The corresponding unit tests can be run giving the appropriate options
+to ``spack unit-test``:
 
 .. code-block:: console
 
-   $ spack test --extension=scripting
+   $ spack unit-test --extension=scripting
 
    ============================================================== test session starts ===============================================================
    platform linux2 -- Python 2.7.15rc1, pytest-3.2.5, py-1.4.34, pluggy-0.4.0

lib/spack/docs/features.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -48,8 +48,8 @@ platform, all on the command line.
    # Add compiler flags using the conventional names
    $ spack install mpileaks@1.1.2 %gcc@4.7.3 cppflags="-O3 -floop-block"
 
-   # Cross-compile for a different architecture with arch=
-   $ spack install mpileaks@1.1.2 arch=bgqos_0
+   # Cross-compile for a different micro-architecture with target=
+   $ spack install mpileaks@1.1.2 target=icelake
 
 Users can specify as many or few options as they care about. Spack
 will fill in the unspecified values with sensible defaults. The two listed

lib/spack/docs/getting_started.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -16,15 +16,18 @@ Prerequisites
 Spack has the following minimum requirements, which must be installed
 before Spack is run:
 
-#. Python 2 (2.6 or 2.7) or 3 (3.5 - 3.8) to run Spack
+#. Python 2 (2.6 or 2.7) or 3 (3.5 - 3.9) to run Spack
 #. A C/C++ compiler for building
 #. The ``make`` executable for building
+#. The ``tar``, ``gzip``, ``bzip2``, ``xz`` and optionally ``zstd``
+   executables for extracting source code
+#. The ``patch`` command to apply patches
 #. The ``git`` and ``curl`` commands for fetching
 #. If using the ``gpg`` subcommand, ``gnupg2`` is required
 
 These requirements can be easily installed on most modern Linux systems;
-on Macintosh, XCode is required.  Spack is designed to run on HPC
-platforms like Cray and BlueGene/Q.  Not all packages should be expected
+on macOS, XCode is required.  Spack is designed to run on HPC
+platforms like Cray.  Not all packages should be expected
 to work on all platforms.  A build matrix showing which packages are
 working on which systems is planned but not yet available.
 
@@ -41,35 +44,58 @@ Getting Spack is easy.  You can clone it from the `github repository
 
 This will create a directory called ``spack``.
 
-^^^^^^^^^^^^^^^^^^^^^^^^
-Add Spack to the Shell
-^^^^^^^^^^^^^^^^^^^^^^^^
+.. _shell-support:
 
-We'll assume that the full path to your downloaded Spack directory is
-in the ``SPACK_ROOT`` environment variable.  Add ``$SPACK_ROOT/bin``
-to your path and you're ready to go:
+^^^^^^^^^^^^^
+Shell support
+^^^^^^^^^^^^^
+
+Once you have cloned Spack, we recommend sourcing the appropriate script
+for your shell:
 
 .. code-block:: console
 
-   $ export PATH=$SPACK_ROOT/bin:$PATH
-   $ spack install libelf
+   # For bash/zsh/sh
+   $ . spack/share/spack/setup-env.sh
 
-For a richer experience, use Spack's shell support:
+   # For tcsh/csh
+   $ source spack/share/spack/setup-env.csh
 
-.. code-block:: console
+   # For fish
+   $ . spack/share/spack/setup-env.fish
 
-   # For bash/zsh users
-   $ export SPACK_ROOT=/path/to/spack
-   $ . $SPACK_ROOT/share/spack/setup-env.sh
+That's it! You're ready to use Spack.
 
-   # For tcsh or csh users (note you must set SPACK_ROOT)
-   $ setenv SPACK_ROOT /path/to/spack
-   $ source $SPACK_ROOT/share/spack/setup-env.csh
+Sourcing these files will put the ``spack`` command in your ``PATH``, set
+up your ``MODULEPATH`` to use Spack's packages, and add other useful
+shell integration for :ref:`certain commands <packaging-shell-support>`,
+:ref:`environments <environments>`, and :ref:`modules <modules>`. For
+``bash``, it also sets up tab completion.
+
+If you do not want to use Spack's shell support, you can always just run
+the ``spack`` command directly from ``spack/bin/spack``.
+
+When the ``spack`` command is executed it searches for an appropriate
+Python interpreter to use, which can be explicitly overridden by setting
+the ``SPACK_PYTHON`` environment variable.  When sourcing the appropriate shell
+setup script, ``SPACK_PYTHON`` will be set to the interpreter found at
+sourcing time, ensuring future invocations of the ``spack`` command will
+continue to use the same consistent python version regardless of changes in
+the environment.
 
 
-This automatically adds Spack to your ``PATH`` and allows the ``spack``
-command to be used to execute spack :ref:`commands <shell-support>` and
-:ref:`useful packaging commands <packaging-shell-support>`.
+^^^^^^^^^^^^^^^^^^
+Check Installation
+^^^^^^^^^^^^^^^^^^
+
+With Spack installed, you should be able to run some basic Spack
+commands.  For example:
+
+.. command-output:: spack spec netcdf-c
+
+In theory, Spack doesn't need any additional installation; just
+download and run!  But in real life, additional steps are usually
+required before Spack can work in a practical sense.  Read on...
 
 ^^^^^^^^^^^^^^^^^
 Clean Environment
@@ -85,17 +111,6 @@ environment*, especially for ``PATH``.  Only software that comes with
 the system, or that you know you wish to use with Spack, should be
 included.  This procedure will avoid many strange build errors.
 
-
-^^^^^^^^^^^^^^^^^^
-Check Installation
-^^^^^^^^^^^^^^^^^^
-
-With Spack installed, you should be able to run some basic Spack
-commands.  For example:
-
-.. command-output:: spack spec netcdf-c
-
-
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 Optional: Alternate Prefix
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -114,15 +129,6 @@ copy of spack installs packages into its own ``$PREFIX/opt``
 directory.
 
 
-^^^^^^^^^^
-Next Steps
-^^^^^^^^^^
-
-In theory, Spack doesn't need any additional installation; just
-download and run!  But in real life, additional steps are usually
-required before Spack can work in a practical sense.  Read on...
-
-
 .. _compiler-config:
 
 ----------------------
@@ -712,8 +718,9 @@ an OpenMPI installed in /opt/local, one would use:
 
     packages:
         openmpi:
-            paths:
-                openmpi@1.10.1: /opt/local
+            externals:
+            - spec: openmpi@1.10.1
+              prefix: /opt/local
             buildable: False
 
 In general, Spack is easier to use and more reliable if it builds all of
@@ -775,8 +782,9 @@ Then add the following to ``~/.spack/packages.yaml``:
 
     packages:
         openssl:
-            paths:
-                openssl@1.0.2g: /usr
+            externals:
+            - spec: openssl@1.0.2g
+              prefix: /usr
             buildable: False
 
 
@@ -791,8 +799,9 @@ to add the following to ``packages.yaml``:
 
     packages:
         netlib-lapack:
-            paths:
-                netlib-lapack@3.6.1: /usr
+            externals:
+            - spec: netlib-lapack@3.6.1
+              prefix: /usr
             buildable: False
         all:
             providers:
@@ -818,7 +827,7 @@ Git
 
 Some Spack packages use ``git`` to download, which might not work on
 some computers.  For example, the following error was
-encountered on a Macintosh during ``spack install julia-master``:
+encountered on a Macintosh during ``spack install julia@master``:
 
 .. code-block:: console
 
@@ -1181,9 +1190,13 @@ Here's an example of an external configuration for cray modules:
 
    packages:
      mpich:
-       modules:
-         mpich@7.3.1%gcc@5.2.0 arch=cray_xc-haswell-CNL10: cray-mpich
-         mpich@7.3.1%intel@16.0.0.109 arch=cray_xc-haswell-CNL10: cray-mpich
+       externals:
+       - spec: "mpich@7.3.1%gcc@5.2.0 arch=cray_xc-haswell-CNL10"
+         modules:
+         - cray-mpich
+       - spec: "mpich@7.3.1%intel@16.0.0.109 arch=cray_xc-haswell-CNL10"
+         modules:
+         - cray-mpich
      all:
        providers:
          mpi: [mpich]
@@ -1195,7 +1208,7 @@ via module load.
 
 .. note::
 
-    For Cray-provided packages, it is best to use ``modules:`` instead of ``paths:``
+    For Cray-provided packages, it is best to use ``modules:`` instead of ``prefix:``
     in ``packages.yaml``, because the Cray Programming Environment heavily relies on
     modules (e.g., loading the ``cray-mpich`` module adds MPI libraries to the
     compiler wrapper link line).
@@ -1211,19 +1224,31 @@ Here is an example of a full packages.yaml used at NERSC
 
    packages:
      mpich:
-       modules:
-         mpich@7.3.1%gcc@5.2.0 arch=cray_xc-CNL10-ivybridge: cray-mpich
-         mpich@7.3.1%intel@16.0.0.109 arch=cray_xc-SuSE11-ivybridge: cray-mpich
+       externals:
+       - spec: "mpich@7.3.1%gcc@5.2.0 arch=cray_xc-CNL10-ivybridge"
+         modules:
+         - cray-mpich
+       - spec: "mpich@7.3.1%intel@16.0.0.109 arch=cray_xc-SuSE11-ivybridge"
+         modules:
+         - cray-mpich
        buildable: False
      netcdf:
-       modules:
-         netcdf@4.3.3.1%gcc@5.2.0 arch=cray_xc-CNL10-ivybridge: cray-netcdf
-         netcdf@4.3.3.1%intel@16.0.0.109 arch=cray_xc-CNL10-ivybridge: cray-netcdf
+       externals:
+       - spec: "netcdf@4.3.3.1%gcc@5.2.0 arch=cray_xc-CNL10-ivybridge"
+         modules:
+         - cray-netcdf
+       - spec: "netcdf@4.3.3.1%intel@16.0.0.109 arch=cray_xc-CNL10-ivybridge"
+         modules:
+         - cray-netcdf
        buildable: False
      hdf5:
-       modules:
-         hdf5@1.8.14%gcc@5.2.0 arch=cray_xc-CNL10-ivybridge: cray-hdf5
-         hdf5@1.8.14%intel@16.0.0.109 arch=cray_xc-CNL10-ivybridge: cray-hdf5
+       externals:
+       - spec: "hdf5@1.8.14%gcc@5.2.0 arch=cray_xc-CNL10-ivybridge"
+         modules:
+         - cray-hdf5
+       - spec: "hdf5@1.8.14%intel@16.0.0.109 arch=cray_xc-CNL10-ivybridge"
+         modules:
+         - cray-hdf5
        buildable: False
      all:
        compiler: [gcc@5.2.0, intel@16.0.0.109]
@@ -1247,6 +1272,6 @@ environment variables may be propagated into containers that are not
 using the Cray programming environment.
 
 To ensure that Spack does not autodetect the Cray programming
-environment, unset the environment variable ``CRAYPE_VERSION``. This
+environment, unset the environment variable ``MODULEPATH``. This
 will cause Spack to treat a linux container on a Cray system as a base
 linux distro.

lib/spack/docs/index.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -85,7 +85,6 @@ or refer to the full manual below.
    packaging_guide
    build_systems
    developer_guide
-   docker_for_developers
 
 .. toctree::
    :maxdepth: 2

lib/spack/docs/known_issues.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -14,7 +14,7 @@ problems if you encounter them.
 Variants are not properly forwarded to dependencies
 ---------------------------------------------------
 
-**Status:** Expected to be fixed in the next release
+**Status:** Expected to be fixed by Spack's new concretizer
 
 Sometimes, a variant of a package can also affect how its dependencies are
 built. For example, in order to build MPI support for a package, it may
@@ -49,15 +49,29 @@ A workaround is to explicitly activate the variants of dependencies as well:
 See https://github.com/spack/spack/issues/267 and
 https://github.com/spack/spack/issues/2546 for further details.
 
+-----------------------------------------------
+depends_on cannot handle recursive dependencies
+-----------------------------------------------
 
-----------------------------
-``spack setup`` doesn't work
-----------------------------
+**Status:** Not yet a work in progress
 
-**Status:** Work in progress
+Although ``depends_on`` can handle any aspect of Spack's spec syntax,
+it currently cannot handle recursive dependencies. If the ``^`` sigil
+appears in a ``depends_on`` statement, the concretizer will hang.
+For example, something like:
 
-Spack provides a ``setup`` command that is useful for the development of
-software outside of Spack. Unfortunately, this command no longer works.
-See https://github.com/spack/spack/issues/2597 and
-https://github.com/spack/spack/issues/2662 for details. This is expected
-to be fixed by https://github.com/spack/spack/pull/2664.
+.. code-block:: python
+
+   depends_on('mfem+cuda ^hypre+cuda', when='+cuda')
+
+
+should be rewritten as:
+
+.. code-block:: python
+
+   depends_on('mfem+cuda', when='+cuda')
+   depends_on('hypre+cuda', when='+cuda')
+
+
+See https://github.com/spack/spack/issues/17660 and
+https://github.com/spack/spack/issues/11160 for more details.

lib/spack/docs/mirrors.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/module_file_support.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -10,14 +10,16 @@ Modules
 =======
 
 The use of module systems to manage user environment in a controlled way
-is a common practice at HPC centers that is often embraced also by individual
-programmers on their development machines. To support this common practice
-Spack integrates with `Environment Modules
-<http://modules.sourceforge.net/>`_  and  `LMod
-<http://lmod.readthedocs.io/en/latest/>`_ by
-providing post-install hooks that generate module files and commands to manipulate them.
+is a common practice at HPC centers that is often embraced also by
+individual programmers on their development machines. To support this
+common practice Spack integrates with `Environment Modules
+<http://modules.sourceforge.net/>`_ and `LMod
+<http://lmod.readthedocs.io/en/latest/>`_ by providing post-install hooks
+that generate module files and commands to manipulate them.
 
-.. _shell-support:
+Modules are one of several ways you can use Spack packages. For other
+options that may fit your use case better, you should also look at
+:ref:`spack load <spack-load>` and :ref:`environments <environments>`.
 
 ----------------------------
 Using module files via Spack
@@ -60,206 +62,9 @@ to load the ``cmake`` module:
 
    $ module load cmake-3.7.2-gcc-6.3.0-fowuuby
 
-Neither of these is particularly pretty, easy to remember, or
-easy to type. Luckily, Spack has its own interface for using modules.
-
-^^^^^^^^^^^^^
-Shell support
-^^^^^^^^^^^^^
-
-To enable additional Spack commands for loading and unloading module files,
-and to add the correct path to ``MODULEPATH``,  you need to source the appropriate
-setup file in the ``$SPACK_ROOT/share/spack`` directory. This will activate shell
-support for the commands that need it. For ``bash``, ``ksh`` or ``zsh`` users:
-
-.. code-block:: console
-
-   $ . ${SPACK_ROOT}/share/spack/setup-env.sh
-
-For ``csh`` and ``tcsh`` instead:
-
-.. code-block:: console
-
-   $ set SPACK_ROOT ...
-   $ source $SPACK_ROOT/share/spack/setup-env.csh
-
-Note that in the latter case it is necessary to explicitly set ``SPACK_ROOT``
-before sourcing the setup file (you will get a meaningful error message
-if you don't).
-
-If you want to have Spack's shell support available on the command line at
-any login you can put this source line in one of the files that are sourced
-at startup (like ``.profile``, ``.bashrc`` or ``.cshrc``). Be aware though
-that the startup time may be slightly increased because of that.
-
-
-.. _cmd-spack-load:
-
-^^^^^^^^^^^^^^^^^^^^^^^
-``spack load / unload``
-^^^^^^^^^^^^^^^^^^^^^^^
-
-Once you have shell support enabled you can use the same spec syntax
-you're used to and you can use the same shortened names you use
-everywhere else in Spack.
-
-For example this will add the ``mpich`` package built with ``gcc`` to your path:
-
-.. code-block:: console
-
-   $ spack install mpich %gcc@4.4.7
-
-   # ... wait for install ...
-
-   $ spack load mpich %gcc@4.4.7
-   $ which mpicc
-   ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpich@3.0.4/bin/mpicc
-
-These commands will add appropriate directories to your ``PATH``,
-``MANPATH``, ``CPATH``, and ``LD_LIBRARY_PATH``.  When you no longer
-want to use a package, you can type unload or unuse similarly:
-
-.. code-block:: console
-
-   $ spack unload mpich %gcc@4.4.7
-
-.. note::
-
-   The ``load`` and ``unload`` subcommands are only available if you
-   have enabled Spack's shell support. These command DO NOT use the
-   underlying Spack-generated module files.
-
-^^^^^^^^^^^^^^^
-Ambiguous specs
-^^^^^^^^^^^^^^^
-
-If a spec used with load/unload or is ambiguous (i.e. more than one
-installed package matches it), then Spack will warn you:
-
-.. code-block:: console
-
-   $ spack load libelf
-   ==> Error: libelf matches multiple packages.
-   Matching packages:
-     libelf@0.8.13%gcc@4.4.7 arch=linux-debian7-x86_64
-     libelf@0.8.13%intel@15.0.0 arch=linux-debian7-x86_64
-   Use a more specific spec
-
-You can either type the ``spack load`` command again with a fully
-qualified argument, or you can add just enough extra constraints to
-identify one package.  For example, above, the key differentiator is
-that one ``libelf`` is built with the Intel compiler, while the other
-used ``gcc``.  You could therefore just type:
-
-.. code-block:: console
-
-   $ spack load libelf %intel
-
-To identify just the one built with the Intel compiler.
-
-.. _cmd-spack-module-loads:
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^
-``spack module tcl loads``
-^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-In some cases, it is desirable to use a Spack-generated module, rather
-than relying on Spack's built-in user-environment modification
-capabilities. To translate a spec into a module name, use ``spack
-module tcl loads`` or ``spack module lmod loads`` depending on the
-module system desired.
-
-
-To load not just a module, but also all the modules it depends on, use
-the ``--dependencies`` option. This is not required for most modules
-because Spack builds binaries with RPATH support.  However, not all
-packages use RPATH to find their dependencies: this can be true in
-particular for Python extensions, which are currently *not* built with
-RPATH.
-
-Scripts to load modules recursively may be made with the command:
-
-.. code-block:: console
-
-    $ spack module tcl loads --dependencies <spec>
-
-An equivalent alternative using `process substitution <http://tldp.org/LDP/abs/html/process-sub.html>`_ is:
-
-.. code-block :: console
-
-    $ source <( spack module tcl loads --dependencies <spec> )
-
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Module Commands for Shell Scripts
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-Although Spack is flexible, the ``module`` command is much faster.
-This could become an issue when emitting a series of ``spack load``
-commands inside a shell script.  By adding the ``--dependencies`` flag,
-``spack module tcl loads`` may also be used to generate code that can be
-cut-and-pasted into a shell script.  For example:
-
-.. code-block:: console
-
-    $ spack module tcl loads --dependencies py-numpy git
-    # bzip2@1.0.6%gcc@4.9.3=linux-x86_64
-    module load bzip2-1.0.6-gcc-4.9.3-ktnrhkrmbbtlvnagfatrarzjojmkvzsx
-    # ncurses@6.0%gcc@4.9.3=linux-x86_64
-    module load ncurses-6.0-gcc-4.9.3-kaazyneh3bjkfnalunchyqtygoe2mncv
-    # zlib@1.2.8%gcc@4.9.3=linux-x86_64
-    module load zlib-1.2.8-gcc-4.9.3-v3ufwaahjnviyvgjcelo36nywx2ufj7z
-    # sqlite@3.8.5%gcc@4.9.3=linux-x86_64
-    module load sqlite-3.8.5-gcc-4.9.3-a3eediswgd5f3rmto7g3szoew5nhehbr
-    # readline@6.3%gcc@4.9.3=linux-x86_64
-    module load readline-6.3-gcc-4.9.3-se6r3lsycrwxyhreg4lqirp6xixxejh3
-    # python@3.5.1%gcc@4.9.3=linux-x86_64
-    module load python-3.5.1-gcc-4.9.3-5q5rsrtjld4u6jiicuvtnx52m7tfhegi
-    # py-setuptools@20.5%gcc@4.9.3=linux-x86_64
-    module load py-setuptools-20.5-gcc-4.9.3-4qr2suj6p6glepnedmwhl4f62x64wxw2
-    # py-nose@1.3.7%gcc@4.9.3=linux-x86_64
-    module load py-nose-1.3.7-gcc-4.9.3-pwhtjw2dvdvfzjwuuztkzr7b4l6zepli
-    # openblas@0.2.17%gcc@4.9.3+shared=linux-x86_64
-    module load openblas-0.2.17-gcc-4.9.3-pw6rmlom7apfsnjtzfttyayzc7nx5e7y
-    # py-numpy@1.11.0%gcc@4.9.3+blas+lapack=linux-x86_64
-    module load py-numpy-1.11.0-gcc-4.9.3-mulodttw5pcyjufva4htsktwty4qd52r
-    # curl@7.47.1%gcc@4.9.3=linux-x86_64
-    module load curl-7.47.1-gcc-4.9.3-ohz3fwsepm3b462p5lnaquv7op7naqbi
-    # autoconf@2.69%gcc@4.9.3=linux-x86_64
-    module load autoconf-2.69-gcc-4.9.3-bkibjqhgqm5e3o423ogfv2y3o6h2uoq4
-    # cmake@3.5.0%gcc@4.9.3~doc+ncurses+openssl~qt=linux-x86_64
-    module load cmake-3.5.0-gcc-4.9.3-x7xnsklmgwla3ubfgzppamtbqk5rwn7t
-    # expat@2.1.0%gcc@4.9.3=linux-x86_64
-    module load expat-2.1.0-gcc-4.9.3-6pkz2ucnk2e62imwakejjvbv6egncppd
-    # git@2.8.0-rc2%gcc@4.9.3+curl+expat=linux-x86_64
-    module load git-2.8.0-rc2-gcc-4.9.3-3bib4hqtnv5xjjoq5ugt3inblt4xrgkd
-
-The script may be further edited by removing unnecessary modules.
-
-
-^^^^^^^^^^^^^^^
-Module Prefixes
-^^^^^^^^^^^^^^^
-
-On some systems, modules are automatically prefixed with a certain
-string; ``spack module tcl loads`` needs to know about that prefix when it
-issues ``module load`` commands.  Add the ``--prefix`` option to your
-``spack module tcl loads`` commands if this is necessary.
-
-For example, consider the following on one system:
-
-.. code-block:: console
-
-    $ module avail
-    linux-SuSE11-x86_64/antlr-2.7.7-gcc-5.3.0-bdpl46y
-
-    $ spack module tcl loads antlr    # WRONG!
-    # antlr@2.7.7%gcc@5.3.0~csharp+cxx~java~python arch=linux-SuSE11-x86_64
-    module load antlr-2.7.7-gcc-5.3.0-bdpl46y
-
-    $ spack module tcl loads --prefix linux-SuSE11-x86_64/ antlr
-    # antlr@2.7.7%gcc@5.3.0~csharp+cxx~java~python arch=linux-SuSE11-x86_64
-    module load linux-SuSE11-x86_64/antlr-2.7.7-gcc-5.3.0-bdpl46y
+Neither of these is particularly pretty, easy to remember, or easy to
+type. Luckily, Spack offers many facilities for customizing the module
+scheme used at your site.
 
 -------------------------
 Module file customization
@@ -589,6 +394,32 @@ that are already in the LMod hierarchy.
    For hierarchies that are deeper than three layers ``lmod spider`` may have some issues.
    See `this discussion on the LMod project <https://github.com/TACC/Lmod/issues/114>`_.
 
+.. _customize-env-modifications:
+
+"""""""""""""""""""""""""""""""""""
+Customize environment modifications
+"""""""""""""""""""""""""""""""""""
+
+You can control which prefixes in a Spack package are added to environment
+variables with the ``prefix_inspections`` section; this section maps relative
+prefixes to the list of environment variables which should be updated with
+those prefixes.
+
+.. code-block:: yaml
+
+  modules:
+    prefix_inspections:
+      bin:
+        - PATH
+      lib:
+        - LIBRARY_PATH
+      '':
+        - CMAKE_PREFIX_PATH
+
+In this case, for a Spack package ``foo`` installed to ``/spack/prefix/foo``,
+the generated module file for ``foo`` would update ``PATH`` to contain
+``/spack/prefix/foo/bin``.
+
 """"""""""""""""""""""""""""""""""""
 Filter out environment modifications
 """"""""""""""""""""""""""""""""""""
@@ -697,3 +528,135 @@ subcommand is ``rm``:
    that are already existing will ask for a confirmation by default. If
    the command is used in a script it is possible though to pass the
    ``-y`` argument, that will skip this safety measure.
+
+
+.. _modules-in-shell-scripts:
+
+------------------------------------
+Using Spack modules in shell scripts
+------------------------------------
+
+The easiest To enable additional Spack commands for loading and unloading
+module files, and to add the correct path to ``MODULEPATH``, you need to
+source the appropriate setup file. Assuming Spack is installed in
+``$SPACK_ROOT``, run the appropriate command for your shell:
+
+.. code-block:: console
+
+   # For bash/zsh/sh
+   $ . $SPACK_ROOT/share/spack/setup-env.sh
+
+   # For tcsh/csh
+   $ source $SPACK_ROOT/share/spack/setup-env.csh
+
+   # For fish
+   $ . $SPACK_ROOT/share/spack/setup-env.fish
+
+If you want to have Spack's shell support available on the command line
+at any login you can put this source line in one of the files that are
+sourced at startup (like ``.profile``, ``.bashrc`` or ``.cshrc``). Be
+aware that the shell startup time may increase slightly as a result.
+
+.. _cmd-spack-module-loads:
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+``spack module tcl loads``
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In some cases, it is desirable to use a Spack-generated module, rather
+than relying on Spack's built-in user-environment modification
+capabilities. To translate a spec into a module name, use ``spack
+module tcl loads`` or ``spack module lmod loads`` depending on the
+module system desired.
+
+
+To load not just a module, but also all the modules it depends on, use
+the ``--dependencies`` option. This is not required for most modules
+because Spack builds binaries with RPATH support.  However, not all
+packages use RPATH to find their dependencies: this can be true in
+particular for Python extensions, which are currently *not* built with
+RPATH.
+
+Scripts to load modules recursively may be made with the command:
+
+.. code-block:: console
+
+    $ spack module tcl loads --dependencies <spec>
+
+An equivalent alternative using `process substitution <http://tldp.org/LDP/abs/html/process-sub.html>`_ is:
+
+.. code-block:: console
+
+    $ source <( spack module tcl loads --dependencies <spec> )
+
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Module Commands for Shell Scripts
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Although Spack is flexible, the ``module`` command is much faster.
+This could become an issue when emitting a series of ``spack load``
+commands inside a shell script.  By adding the ``--dependencies`` flag,
+``spack module tcl loads`` may also be used to generate code that can be
+cut-and-pasted into a shell script.  For example:
+
+.. code-block:: console
+
+    $ spack module tcl loads --dependencies py-numpy git
+    # bzip2@1.0.6%gcc@4.9.3=linux-x86_64
+    module load bzip2-1.0.6-gcc-4.9.3-ktnrhkrmbbtlvnagfatrarzjojmkvzsx
+    # ncurses@6.0%gcc@4.9.3=linux-x86_64
+    module load ncurses-6.0-gcc-4.9.3-kaazyneh3bjkfnalunchyqtygoe2mncv
+    # zlib@1.2.8%gcc@4.9.3=linux-x86_64
+    module load zlib-1.2.8-gcc-4.9.3-v3ufwaahjnviyvgjcelo36nywx2ufj7z
+    # sqlite@3.8.5%gcc@4.9.3=linux-x86_64
+    module load sqlite-3.8.5-gcc-4.9.3-a3eediswgd5f3rmto7g3szoew5nhehbr
+    # readline@6.3%gcc@4.9.3=linux-x86_64
+    module load readline-6.3-gcc-4.9.3-se6r3lsycrwxyhreg4lqirp6xixxejh3
+    # python@3.5.1%gcc@4.9.3=linux-x86_64
+    module load python-3.5.1-gcc-4.9.3-5q5rsrtjld4u6jiicuvtnx52m7tfhegi
+    # py-setuptools@20.5%gcc@4.9.3=linux-x86_64
+    module load py-setuptools-20.5-gcc-4.9.3-4qr2suj6p6glepnedmwhl4f62x64wxw2
+    # py-nose@1.3.7%gcc@4.9.3=linux-x86_64
+    module load py-nose-1.3.7-gcc-4.9.3-pwhtjw2dvdvfzjwuuztkzr7b4l6zepli
+    # openblas@0.2.17%gcc@4.9.3+shared=linux-x86_64
+    module load openblas-0.2.17-gcc-4.9.3-pw6rmlom7apfsnjtzfttyayzc7nx5e7y
+    # py-numpy@1.11.0%gcc@4.9.3+blas+lapack=linux-x86_64
+    module load py-numpy-1.11.0-gcc-4.9.3-mulodttw5pcyjufva4htsktwty4qd52r
+    # curl@7.47.1%gcc@4.9.3=linux-x86_64
+    module load curl-7.47.1-gcc-4.9.3-ohz3fwsepm3b462p5lnaquv7op7naqbi
+    # autoconf@2.69%gcc@4.9.3=linux-x86_64
+    module load autoconf-2.69-gcc-4.9.3-bkibjqhgqm5e3o423ogfv2y3o6h2uoq4
+    # cmake@3.5.0%gcc@4.9.3~doc+ncurses+openssl~qt=linux-x86_64
+    module load cmake-3.5.0-gcc-4.9.3-x7xnsklmgwla3ubfgzppamtbqk5rwn7t
+    # expat@2.1.0%gcc@4.9.3=linux-x86_64
+    module load expat-2.1.0-gcc-4.9.3-6pkz2ucnk2e62imwakejjvbv6egncppd
+    # git@2.8.0-rc2%gcc@4.9.3+curl+expat=linux-x86_64
+    module load git-2.8.0-rc2-gcc-4.9.3-3bib4hqtnv5xjjoq5ugt3inblt4xrgkd
+
+The script may be further edited by removing unnecessary modules.
+
+
+^^^^^^^^^^^^^^^
+Module Prefixes
+^^^^^^^^^^^^^^^
+
+On some systems, modules are automatically prefixed with a certain
+string; ``spack module tcl loads`` needs to know about that prefix when it
+issues ``module load`` commands.  Add the ``--prefix`` option to your
+``spack module tcl loads`` commands if this is necessary.
+
+For example, consider the following on one system:
+
+.. code-block:: console
+
+    $ module avail
+    linux-SuSE11-x86_64/antlr-2.7.7-gcc-5.3.0-bdpl46y
+
+    $ spack module tcl loads antlr    # WRONG!
+    # antlr@2.7.7%gcc@5.3.0~csharp+cxx~java~python arch=linux-SuSE11-x86_64
+    module load antlr-2.7.7-gcc-5.3.0-bdpl46y
+
+    $ spack module tcl loads --prefix linux-SuSE11-x86_64/ antlr
+    # antlr@2.7.7%gcc@5.3.0~csharp+cxx~java~python arch=linux-SuSE11-x86_64
+    module load linux-SuSE11-x86_64/antlr-2.7.7-gcc-5.3.0-bdpl46y

lib/spack/docs/package_list.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -10,8 +10,8 @@ Package List
 ============
 
 This is a list of things you can install using Spack.  It is
-automatically generated based on the packages in the latest Spack
-release.
+automatically generated based on the packages in this Spack
+version.
 
 .. raw:: html
    :file: package_list.html

lib/spack/docs/packaging_guide.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -612,6 +612,62 @@ it executable, then runs it with some arguments.
        installer = Executable(self.stage.archive_file)
        installer('--prefix=%s' % prefix, 'arg1', 'arg2', 'etc.')
 
+
+^^^^^^^^^^^^^^^^^^^^^^^^
+Deprecating old versions
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+There are many reasons to remove old versions of software:
+
+#. Security vulnerabilities (most serious reason)
+#. Changing build systems that increase package complexity
+#. Changing dependencies/patches/resources/flags that increase package complexity
+#. Maintainer/developer inability/unwillingness to support old versions
+#. No longer available for download (right to be forgotten)
+#. Package or version rename
+
+At the same time, there are many reasons to keep old versions of software:
+
+#. Reproducibility
+#. Requirements for older packages (e.g. some packages still rely on Qt 3)
+
+In general, you should not remove old versions from a ``package.py``. Instead,
+you should first deprecate them using the following syntax:
+
+.. code-block:: python
+
+   version('1.2.3', sha256='...', deprecated=True)
+
+
+This has two effects. First, ``spack info`` will no longer advertise that
+version. Second, commands like ``spack install`` that fetch the package will
+require user approval:
+
+.. code-block:: console
+
+   $ spack install openssl@1.0.1e
+   ==> Warning: openssl@1.0.1e is deprecated and may be removed in a future Spack release.
+   ==>   Fetch anyway? [y/N]
+
+
+If you use ``spack install --deprecated``, this check can be skipped.
+
+This also applies to package recipes that are renamed or removed. You should
+first deprecate all versions before removing a package. If you need to rename
+it, you can deprecate the old package and create a new package at the same
+time.
+
+Version deprecations should always last at least one Spack minor release cycle
+before the version is completely removed. For example, if a version is
+deprecated in Spack 0.16.0, it should not be removed until Spack 0.17.0. No
+version should be removed without such a deprecation process. This gives users
+a chance to complain about the deprecation in case the old version is needed
+for some application. If you require a deprecated version of a package, simply
+submit a PR to remove ``deprecated=True`` from the package. However, you may be
+asked to help maintain this version of the package if the current maintainers
+are unwilling to support this older version.
+
+
 ^^^^^^^^^^^^^^^^
 Download caching
 ^^^^^^^^^^^^^^^^
@@ -645,7 +701,7 @@ multiple fields based on delimiters such as ``.``, ``-`` etc. Then
 matching fields are compared using the rules below:
 
 #. The following develop-like strings are greater (newer) than all
-   numbers and are ordered as ``develop > master > head > trunk``.
+   numbers and are ordered as ``develop > main > master > head > trunk``.
 
 #. Numbers are all less than the chosen develop-like strings above,
    and are sorted numerically.
@@ -1778,8 +1834,18 @@ RPATHs in Spack are handled in one of three ways:
 Parallel builds
 ---------------
 
+Spack supports parallel builds on an individual package and at the
+installation level.  Package-level parallelism is established by the
+``--jobs`` option and its configuration and package recipe equivalents.
+Installation-level parallelism is driven by the DAG(s) of the requested
+package or packages.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Package-level build parallelism
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
 By default, Spack will invoke ``make()``, or any other similar tool,
-with a ``-j <njobs>`` argument, so that builds run in parallel.
+with a ``-j <njobs>`` argument, so those builds run in parallel.
 The parallelism is determined by the value of the ``build_jobs`` entry
 in ``config.yaml`` (see :ref:`here <build-jobs>` for more details on
 how this value is computed).
@@ -1827,6 +1893,50 @@ you set ``parallel`` to ``False`` at the package level, then each call
 to ``make()`` will be sequential by default, but packagers can call
 ``make(parallel=True)`` to override it.
 
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Install-level build parallelism
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Spack supports the concurrent installation of packages within a Spack
+instance across multiple processes using file system locks.  This
+parallelism is separate from the package-level achieved through build
+systems' use of the ``-j <njobs>`` option.  With install-level parallelism,
+processes coordinate the installation of the dependencies of specs
+provided on the command line and as part of an environment build with
+only **one process** being allowed to install a given package at a time.
+Refer to :ref:`Dependencies` for more information on dependencies and
+:ref:`installing-environment` for how to install an environment.
+
+Concurrent processes may be any combination of interactive sessions and
+batch jobs.  Which means a ``spack install`` can be running in a terminal
+window while a batch job is running ``spack install`` on the same or
+overlapping dependencies without any process trying to re-do the work of
+another.
+
+For example, if you are using SLURM, you could launch an installation
+of ``mpich`` using the following command:
+
+.. code-block:: console
+
+   $ srun -N 2 -n 8 spack install -j 4 mpich@3.3.2
+
+This will create eight concurrent, four-job installs on two different
+nodes.
+
+Alternatively, you could run the same installs on one node by entering
+the following at the command line of a bash shell:
+
+.. code-block:: console
+
+   $ for i in {1..12}; do nohup spack install -j 4 mpich@3.3.2 >> mpich_install.txt 2>&1 &; done
+
+.. note::
+
+   The effective parallelism is based on the maximum number of packages
+   that can be installed at the same time, which is limited by the
+   number of packages with no (remaining) uninstalled dependencies.
+
+
 .. _dependencies:
 
 ------------
@@ -1967,22 +2077,29 @@ exactly what kind of a dependency you need. For example:
    depends_on('cmake', type='build')
    depends_on('py-numpy', type=('build', 'run'))
    depends_on('libelf', type=('build', 'link'))
+   depends_on('py-pytest', type='test')
 
 The following dependency types are available:
 
-* **"build"**: made available during the project's build. The package will
-  be added to ``PATH``, the compiler include paths, and ``PYTHONPATH``.
-  Other projects which depend on this one will not have these modified
-  (building project X doesn't need project Y's build dependencies).
-* **"link"**: the project is linked to by the project. The package will be
-  added to the current package's ``rpath``.
-* **"run"**: the project is used by the project at runtime. The package will
-  be added to ``PATH`` and ``PYTHONPATH``.
+* **"build"**: the dependency will be added to the ``PATH`` and
+  ``PYTHONPATH`` at build-time.
+* **"link"**: the dependency will be added to Spack's compiler
+  wrappers, automatically injecting the appropriate linker flags,
+  including ``-I``, ``-L``, and RPATH/RUNPATH handling.
+* **"run"**: the dependency will be added to the ``PATH`` and
+  ``PYTHONPATH`` at run-time. This is true for both ``spack load``
+  and the module files Spack writes.
+* **"test"**: the dependency will be added to the ``PATH`` and
+  ``PYTHONPATH`` at build-time. The only difference between
+  "build" and "test" is that test dependencies are only built
+  if the user requests unit tests with ``spack install --test``.
 
 One of the advantages of the ``build`` dependency type is that although the
 dependency needs to be installed in order for the package to be built, it
 can be uninstalled without concern afterwards. ``link`` and ``run`` disallow
-this because uninstalling the dependency would break the package.
+this because uninstalling the dependency would break the package. Another
+consequence of this is that ``build``-only dependencies do not affect the
+hash of the package. The same is true for ``test`` dependencies.
 
 If the dependency type is not specified, Spack uses a default of
 ``('build', 'link')``. This is the common case for compiler languages.
@@ -2003,7 +2120,8 @@ package. In that case, you could say something like:
 
 .. code-block:: python
 
-   variant('mpi', default=False)
+   variant('mpi', default=False, description='Enable MPI support')
+
    depends_on('mpi', when='+mpi')
 
 ``when`` can include constraints on the variant, version, compiler, etc. and
@@ -2682,12 +2800,14 @@ The classes that are currently provided by Spack are:
     |                               | built using CMake                |
     +-------------------------------+----------------------------------+
     | :py:class:`.CudaPackage`      | A helper class for packages that |
-    |                               | use CUDA. It is intended to be   |
-    |                               | used in combination with others  |
+    |                               | use CUDA                         |
     +-------------------------------+----------------------------------+
     | :py:class:`.QMakePackage`     | Specialized class for packages   |
     |                               | build using QMake                |
     +-------------------------------+----------------------------------+
+    | :py:class:`.ROCmPackage`      | A helper class for packages that |
+    |                               | use ROCm                         |
+    +-------------------------------+----------------------------------+
     | :py:class:`.SConsPackage`     | Specialized class for packages   |
     |                               | built using SCons                |
     +-------------------------------+----------------------------------+
@@ -3108,7 +3228,7 @@ differ from package to package. In order to make the ``install()`` method
 independent of the choice of ``Blas`` implementation, each package which
 provides it implements ``@property def blas_libs(self):`` to return an object
 of
-`LibraryList <http://spack.readthedocs.io/en/latest/llnl.util.html#llnl.util.filesystem.LibraryList>`_
+`LibraryList <https://spack.readthedocs.io/en/latest/llnl.util.html#llnl.util.filesystem.LibraryList>`_
 type which simplifies usage of a set of libraries.
 The same applies to packages which provide ``Lapack`` and ``ScaLapack``.
 Package developers are requested to use this interface. Common usage cases are:
@@ -3143,7 +3263,7 @@ Package developers are requested to use this interface. Common usage cases are:
 
 
 For more information, see documentation of
-`LibraryList <http://spack.readthedocs.io/en/latest/llnl.util.html#llnl.util.filesystem.LibraryList>`_
+`LibraryList <https://spack.readthedocs.io/en/latest/llnl.util.html#llnl.util.filesystem.LibraryList>`_
 class.
 
 
@@ -3891,6 +4011,214 @@ using the ``run_before`` decorator.
 
     The API for adding tests is not yet considered stable and may change drastically in future releases.
 
+.. _cmd-spack-test:
+
+^^^^^^^^^^^^^
+Install Tests
+^^^^^^^^^^^^^
+
+.. warning::
+
+   The API for adding and running install tests is not yet considered
+   stable and may change drastically in future releases. Packages with
+   install tests will be refactored to match changes to the API.
+
+While build tests are integrated with the build system, install tests
+are for testing package installations independent of the build process.
+
+Install tests are executed in a test stage directory that defaults to
+``~/.spack/test``. You can change the location in the high-level ``config``
+by adding the ``test_stage`` path as follows:
+
+.. code-block:: yaml
+
+   config:
+     test_stage: /path/to/stage
+
+""""""""""""""""""""
+Adding install tests
+""""""""""""""""""""
+
+Install tests are added to a package by defining a ``test`` method
+with the following signature:
+
+.. code-block:: python
+
+   def test(self):
+
+These tests run in an environment that provides access to the
+package and all of its dependencies, including ``test``-type
+dependencies.
+
+Standard python ``assert`` statements and other error reporting
+mechanisms can be used in the ``test`` method. Spack will report
+such errors as test failures.
+
+You can implement multiple tests (or test parts) within the ``test``
+method, where each is run separately and testing continues after
+failures by using the ``run_test`` method. The signature for the
+method is:
+
+.. code-block:: python
+
+   def run_test(self, exe, options=[], expected=[], status=0, installed=False,
+                purpose='', skip_missing=False, work_dir=None):
+
+The test fails if there is no executable named ``exe`` found in the
+paths of the ``PATH`` variable **unless** ``skip_missing`` is ``True``.
+The test also fails if the resulting path is not within the prefix of
+the package being tested when ``installed`` is ``True``.
+
+The executable runs in ``work_dir``, when specified, using the provided
+``options``. The return code is checked against the ``status`` argument,
+which can be an integer or list of integers representing status codes
+corresponding to successful execution (e.g. ``status=[0,3,7]``).
+Spack also checks that every string in ``expected`` is a regex matching
+part of the output from the test run (e.g.
+``expected=['completed successfully', 'converged in']``). Default behavior
+is to behave as though ``status=[0]`` and ``expected=[]`` are specified.
+
+Output from the test is written to its log file. The ``purpose`` argument
+serves as the heading in text logs to highlight the start of each test part.
+
+"""""""""""""""""""""""""
+Enabling test compilation
+"""""""""""""""""""""""""
+
+Some tests may require access to the compiler with which the package
+was built, especially to test library-only packages. You must enable
+loading the package's compiler configuration by setting the attribute
+``test_requires_compiler`` to ``True``. Doing so makes the compiler
+available in the test environment through the canonical environment
+variables (``CC``, ``CXX``, ``FC``, ``F77``).
+
+"""""""""""""""""""""""
+Adding build-time files
+"""""""""""""""""""""""
+
+.. note::
+
+    We highly recommend the re-use of build-time tests and input files
+    for testing installed software.  These files are easier to keep
+    synchronized with the software than creating custom install tests.
+
+You can use the ``cache_extra_test_sources`` method copy directories
+and or files from the build stage directory to the package's installation
+directory.
+
+For example, a package method for copying everything in the ``tests``
+subdirectory plus the ``foo.c`` and ``bar.c`` files from ``examples``
+can be implemented as follows:
+
+.. code-block:: python
+
+   @run_after('install')
+   def cache_test_sources(self):
+       srcs = ['tests', 'examples/foo.c', 'examples/bar.c']
+       self.cache_extra_test_sources(srcs)
+
+The use of the ``run_after`` directive ensures the associated files
+are copied **after** the package is installed during the build process.
+
+The method copies files to the package's metadata directory under
+the ``self.install_test_root``. All files in the package source's
+``tests`` directory for the example above will be copied to the
+``join_path(self.install_test_root, 'tests')`` directory. The two
+files listed under the staged ``examples`` directory will be copied
+to the ``join_path(self.install_test_root, 'examples')`` directory.
+
+.. note::
+
+    While source and input files are generally recommended, binaries
+    may also be cached by the build process for install testing.
+
+"""""""""""""""""""
+Adding custom files
+"""""""""""""""""""
+
+Some tests may require additional files not available from the build.
+Examples include:
+
+- test source files
+- test input files
+- test build scripts
+- expected test output
+
+These extra files should be added to the ``test`` subdirectory of the
+package in the repository. Spack will automaticaly copy any files in
+that directory to the test staging directory during install testing.
+The ``test`` method can access those files from the
+``self.test_suite.current_test_data_dir`` directory.
+
+.. _cmd-spack-test-list:
+
+"""""""""""""""""""
+``spack test list``
+"""""""""""""""""""
+
+Packages available for install testing can be found using the
+``spack test list`` command. The command outputs all installed
+packages that have defined ``test`` methods.
+
+.. _cmd-spack-test-run:
+
+""""""""""""""""""
+``spack test run``
+""""""""""""""""""
+
+Install tests can be run for one or more installed packages using
+the ``spack test run`` command. A ``test suite`` is created from
+the provided specs.  If no specs are provided it will test all specs
+in the active environment or all specs installed in Spack if no
+environment is active.
+
+Test suites can be named using the ``--alias`` option. Unaliased
+Test suites will use the content hash of their specs as their name.
+
+Some of the more commonly used debugging options are:
+
+- ``--fail-fast`` stops testing each package after the first failure
+- ``--fail-first`` stops testing packages after the first failure
+
+Test output is written to a text log file by default but ``junit``
+and ``cdash`` are outputs are available through the ``--log-format``
+option.
+
+.. _cmd-spack-test-results:
+
+""""""""""""""""""""""
+``spack test results``
+""""""""""""""""""""""
+
+The ``spack test results`` command shows results for all completed
+test suites. Providing the alias or content hash limits reporting
+to the corresponding test suite.
+
+The ``--logs`` option includes the output generated by the associated
+test(s) to facilitate debugging.
+
+The ``--failed`` option limits results shown to that of the failed
+tests, if any, of matching packages.
+
+.. _cmd-spack-test-find:
+
+"""""""""""""""""""
+``spack test find``
+"""""""""""""""""""
+
+The ``spack test find`` command lists the aliases or content hashes
+of all test suites whose results are available.
+
+.. _cmd-spack-test-remove:
+
+"""""""""""""""""""""
+``spack test remove``
+"""""""""""""""""""""
+
+The ``spack test remove`` command removes test suites to declutter
+the test results directory. You are prompted to confirm the removal
+of each test suite **unless** you use the ``--yes-to-all`` option.
+
 .. _file-manipulation:
 
 ---------------------------
@@ -4054,21 +4382,223 @@ File functions
 Making a package discoverable with ``spack external find``
 ----------------------------------------------------------
 
-To make a package discoverable with
-:ref:`spack external find <cmd-spack-external-find>` you must
-define one or more executables associated with the package and must
-implement a method to generate a Spec when given an executable.
+The simplest way to make a package discoverable with
+:ref:`spack external find <cmd-spack-external-find>` is to:
 
-The executables are specified as a package level ``executables``
-attribute which is a list of strings (see example below); each string
-is treated as a regular expression (e.g. 'gcc' would match 'gcc', 'gcc-8.3',
-'my-weird-gcc', etc.).
+1. Define the executables associated with the package
+2. Implement a method to determine the versions of these executables
 
-The method ``determine_spec_details`` has the following signature:
+^^^^^^^^^^^^^^^^^
+Minimal detection
+^^^^^^^^^^^^^^^^^
+
+The first step is fairly simple, as it requires only to
+specify a package level ``executables`` attribute:
 
 .. code-block:: python
 
-   def determine_spec_details(prefix, exes_in_prefix):
+   class Foo(Package):
+       # Each string provided here is treated as a regular expression, and
+       # would match for example 'foo', 'foobar', and 'bazfoo'.
+       executables = ['foo']
+
+This attribute must be a list of strings. Each string is a regular
+expression (e.g. 'gcc' would match 'gcc', 'gcc-8.3', 'my-weird-gcc', etc.) to
+determine a set of system executables that might be part or this package. Note
+that to match only executables named 'gcc' the regular expression ``'^gcc$'``
+must be used.
+
+Finally to determine the version of each executable the ``determine_version``
+method must be implemented:
+
+.. code-block:: python
+
+   @classmethod
+   def determine_version(cls, exe):
+       """Return either the version of the executable passed as argument
+       or ``None`` if the version cannot be determined.
+
+       Args:
+           exe (str): absolute path to the executable being examined
+       """
+
+This method receives as input the path to a single executable and must return
+as output its version as a string; if the user cannot determine the version
+or determines that the executable is not an instance of the package, they can
+return None and the exe will be discarded as a candidate.
+Implementing the two steps above is mandatory, and gives the package the
+basic ability to detect if a spec is present on the system at a given version.
+
+.. note::
+   Any executable for which the ``determine_version`` method returns ``None``
+   will be discarded and won't appear in later stages of the workflow described below.
+
+^^^^^^^^^^^^^^^^^^^^^^^^
+Additional functionality
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+Besides the two mandatory steps described above, there are also optional
+methods that can be implemented to either increase the amount of details
+being detected or improve the robustness of the detection logic in a package.
+
+""""""""""""""""""""""""""""""
+Variants and custom attributes
+""""""""""""""""""""""""""""""
+
+The ``determine_variants`` method can be optionally implemented in a package
+to detect additional details of the spec:
+
+.. code-block:: python
+
+   @classmethod
+   def determine_variants(cls, exes, version_str):
+       """Return either a variant string, a tuple of a variant string
+       and a dictionary of extra attributes that will be recorded in
+       packages.yaml or a list of those items.
+
+       Args:
+           exes (list of str): list of executables (absolute paths) that
+               live in the same prefix and share the same version
+           version_str (str): version associated with the list of
+               executables, as detected by ``determine_version``
+       """
+
+This method takes as input a list of executables that live in the same prefix and
+share the same version string, and returns either:
+
+1. A variant string
+2. A tuple of a variant string and a dictionary of extra attributes
+3. A list of items matching either 1 or 2 (if multiple specs are detected
+   from the set of executables)
+
+If extra attributes are returned, they will be recorded in ``packages.yaml``
+and be available for later reuse. As an example, the ``gcc`` package will record
+by default the different compilers found and an entry in ``packages.yaml``
+would look like:
+
+.. code-block:: yaml
+
+   packages:
+     gcc:
+       externals:
+       - spec: 'gcc@9.0.1 languages=c,c++,fortran'
+         prefix: /usr
+         extra_attributes:
+           compilers:
+             c: /usr/bin/x86_64-linux-gnu-gcc-9
+             c++: /usr/bin/x86_64-linux-gnu-g++-9
+             fortran: /usr/bin/x86_64-linux-gnu-gfortran-9
+
+This allows us, for instance, to keep track of executables that would be named
+differently if built by Spack (e.g. ``x86_64-linux-gnu-gcc-9``
+instead of just ``gcc``).
+
+.. TODO: we need to gather some more experience on overriding 'prefix'
+   and other special keywords in extra attributes, but as soon as we are
+   confident that this is the way to go we should document the process.
+   See https://github.com/spack/spack/pull/16526#issuecomment-653783204
+
+"""""""""""""""""""""""""""
+Filter matching executables
+"""""""""""""""""""""""""""
+
+Sometimes defining the appropriate regex for the ``executables``
+attribute might prove to be difficult, especially if one has to
+deal with corner cases or exclude "red herrings". To help keeping
+the regular expressions as simple as possible, each package can
+optionally implement a ``filter_executables`` method:
+
+.. code-block:: python
+
+    @classmethod
+    def filter_detected_exes(cls, prefix, exes_in_prefix):
+        """Return a filtered list of the executables in prefix"""
+
+which takes as input a prefix and a list of matching executables and
+returns a filtered list of said executables.
+
+Using this method has the advantage of allowing custom logic for
+filtering, and does not restrict the user to regular expressions
+only.  Consider the case of detecting the GNU C++ compiler. If we
+try to search for executables that match ``g++``, that would have
+the unwanted side effect of selecting also ``clang++`` - which is
+a C++ compiler provided by another package - if present on the system.
+Trying to select executables that contain ``g++`` but not ``clang``
+would be quite complicated to do using regex only. Employing the
+``filter_detected_exes`` method it becomes:
+
+.. code-block:: python
+
+   class Gcc(Package):
+      executables = ['g++']
+
+      def filter_detected_exes(cls, prefix, exes_in_prefix):
+         return [x for x in exes_in_prefix if 'clang' not in x]
+
+Another possibility that this method opens is to apply certain
+filtering logic when specific conditions are met (e.g. take some
+decisions on an OS and not on another).
+
+^^^^^^^^^^^^^^^^^^
+Validate detection
+^^^^^^^^^^^^^^^^^^
+
+To increase detection robustness, packagers may also implement a method
+to validate the detected Spec objects:
+
+.. code-block:: python
+
+   @classmethod
+   def validate_detected_spec(cls, spec, extra_attributes):
+       """Validate a detected spec. Raise an exception if validation fails."""
+
+This method receives a detected spec along with its extra attributes and can be
+used to check that certain conditions are met by the spec. Packagers can either
+use assertions or raise an ``InvalidSpecDetected`` exception when the check fails.
+In case the conditions are not honored the spec will be discarded and any message
+associated with the assertion or the exception will be logged as the reason for
+discarding it.
+
+As an example, a package that wants to check that the ``compilers`` attribute is
+in the extra attributes can implement this method like this:
+
+.. code-block:: python
+
+   @classmethod
+   def validate_detected_spec(cls, spec, extra_attributes):
+       """Check that 'compilers' is in the extra attributes."""
+       msg = ('the extra attribute "compilers" must be set for '
+              'the detected spec "{0}"'.format(spec))
+       assert 'compilers' in extra_attributes, msg
+
+or like this:
+
+.. code-block:: python
+
+   @classmethod
+   def validate_detected_spec(cls, spec, extra_attributes):
+       """Check that 'compilers' is in the extra attributes."""
+       if 'compilers' not in extra_attributes:
+           msg = ('the extra attribute "compilers" must be set for '
+                  'the detected spec "{0}"'.format(spec))
+           raise InvalidSpecDetected(msg)
+
+.. _determine_spec_details:
+
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Custom detection workflow
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In the rare case when the mechanisms described so far don't fit the
+detection of a package, the implementation of all the methods above
+can be disregarded and instead a custom ``determine_spec_details``
+method can be implemented directly in the package class (note that
+the definition of the ``executables`` attribute is still required):
+
+.. code-block:: python
+
+   @classmethod
+   def determine_spec_details(cls, prefix, exes_in_prefix):
        # exes_in_prefix = a set of paths, each path is an executable
        # prefix = a prefix that is common to each path in exes_in_prefix
 
@@ -4076,14 +4606,13 @@ The method ``determine_spec_details`` has the following signature:
        # the package. Return one or more Specs for each instance of the
        # package which is thought to be installed in the provided prefix
 
-``determine_spec_details`` takes as parameters a set of discovered
-executables (which match those specified by the user) as well as a
-common prefix shared by all of those executables. The function must
-return one or more Specs associated with the executables (it can also
-return ``None`` to indicate that no provided executables are associated
-with the package).
+This method takes as input a set of discovered executables (which match
+those specified by the user) as well as a common prefix shared by all
+of those executables. The function must return one or more :py:class:`spack.spec.Spec` associated
+with the executables (it can also return ``None`` to indicate that no
+provided executables are associated with the package).
 
-Say for example we have a package called ``foo-package`` which
+As an example, consider a made-up package called ``foo-package`` which
 builds an executable called ``foo``. ``FooPackage`` would appear as
 follows:
 
@@ -4107,10 +4636,12 @@ follows:
                return
            # This implementation is lazy and only checks the first candidate
            exe_path = candidates[0]
-           exe = spack.util.executable.Executable(exe_path)
-           output = exe('--version')
+           exe = Executable(exe_path)
+           output = exe('--version', output=str, error=str)
            version_str = ...  # parse output for version string
-           return Spec('foo-package@{0}'.format(version_str))
+           return Spec.from_detection(
+               'foo-package@{0}'.format(version_str)
+           )
 
 .. _package-lifecycle:
 
@@ -4474,119 +5005,3 @@ might write:
    DWARF_PREFIX = $(spack location --install-dir libdwarf)
    CXXFLAGS += -I$DWARF_PREFIX/include
    CXXFLAGS += -L$DWARF_PREFIX/lib
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Build System Configuration Support
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-Imagine a developer creating a CMake or Autotools-based project in a
-local directory, which depends on libraries A-Z.  Once Spack has
-installed those dependencies, one would like to run ``cmake`` with
-appropriate command line and environment so CMake can find them.  The
-``spack setup`` command does this conveniently, producing a CMake
-configuration that is essentially the same as how Spack *would have*
-configured the project.  This can be demonstrated with a usage
-example:
-
-.. code-block:: console
-
-   $ cd myproject
-   $ spack setup myproject@local
-   $ mkdir build; cd build
-   $ ../spconfig.py ..
-   $ make
-   $ make install
-
-Notes:
-
-* Spack must have ``myproject/package.py`` in its repository for
-  this to work.
-* ``spack setup`` produces the executable script ``spconfig.py`` in
-  the local directory, and also creates the module file for the
-  package.  ``spconfig.py`` is normally run from the user's
-  out-of-source build directory.
-* The version number given to ``spack setup`` is arbitrary, just
-  like ``spack diy``.  ``myproject/package.py`` does not need to
-  have any valid downloadable versions listed (typical when a
-  project is new).
-* spconfig.py produces a CMake configuration that *does not* use the
-  Spack wrappers.  Any resulting binaries *will not* use RPATH,
-  unless the user has enabled it.  This is recommended for
-  development purposes, not production.
-* ``spconfig.py`` is human readable, and can serve as a developer
-  reference of what dependencies are being used.
-* ``make install`` installs the package into the Spack repository,
-  where it may be used by other Spack packages.
-* CMake-generated makefiles re-run CMake in some circumstances.  Use
-  of ``spconfig.py`` breaks this behavior, requiring the developer
-  to manually re-run ``spconfig.py`` when a ``CMakeLists.txt`` file
-  has changed.
-
-^^^^^^^^^^^^
-CMakePackage
-^^^^^^^^^^^^
-
-In order to enable ``spack setup`` functionality, the author of
-``myproject/package.py`` must subclass from ``CMakePackage`` instead
-of the standard ``Package`` superclass.  Because CMake is
-standardized, the packager does not need to tell Spack how to run
-``cmake; make; make install``.  Instead the packager only needs to
-create (optional) methods ``configure_args()`` and ``configure_env()``, which
-provide the arguments (as a list) and extra environment variables (as
-a dict) to provide to the ``cmake`` command.  Usually, these will
-translate variant flags into CMake definitions.  For example:
-
-.. code-block:: python
-
-   def cmake_args(self):
-       spec = self.spec
-       return [
-           '-DUSE_EVERYTRACE=%s' % ('YES' if '+everytrace' in spec else 'NO'),
-           '-DBUILD_PYTHON=%s' % ('YES' if '+python' in spec else 'NO'),
-           '-DBUILD_GRIDGEN=%s' % ('YES' if '+gridgen' in spec else 'NO'),
-           '-DBUILD_COUPLER=%s' % ('YES' if '+coupler' in spec else 'NO'),
-           '-DUSE_PISM=%s' % ('YES' if '+pism' in spec else 'NO')
-       ]
-
-If needed, a packager may also override methods defined in
-``StagedPackage`` (see below).
-
-^^^^^^^^^^^^^
-StagedPackage
-^^^^^^^^^^^^^
-
-``CMakePackage`` is implemented by subclassing the ``StagedPackage``
-superclass, which breaks down the standard ``Package.install()``
-method into several sub-stages: ``setup``, ``configure``, ``build``
-and ``install``.  Details:
-
-* Instead of implementing the standard ``install()`` method, package
-  authors implement the methods for the sub-stages
-  ``install_setup()``, ``install_configure()``,
-  ``install_build()``, and ``install_install()``.
-
-* The ``spack install`` command runs the sub-stages ``configure``,
-  ``build`` and ``install`` in order.  (The ``setup`` stage is
-  not run by default; see below).
-* The ``spack setup`` command runs the sub-stages ``setup``
-  and a dummy install (to create the module file).
-* The sub-stage install methods take no arguments (other than
-  ``self``).  The arguments ``spec`` and ``prefix`` to the standard
-  ``install()`` method may be accessed via ``self.spec`` and
-  ``self.prefix``.
-
-^^^^^^^^^^^^^
-GNU Autotools
-^^^^^^^^^^^^^
-
-The ``setup`` functionality is currently only available for
-CMake-based packages.  Extending this functionality to GNU
-Autotools-based packages would be easy (and should be done by a
-developer who actively uses Autotools).  Packages that use
-non-standard build systems can gain ``setup`` functionality by
-subclassing ``StagedPackage`` directly.
-
-.. Emacs local variables
-   Local Variables:
-   fill-column: 79
-   End:

lib/spack/docs/pipelines.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2019 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -45,7 +45,7 @@ for setting up a build pipeline are as follows:
         tags:
           - <custom-tag>
         script:
-          - spack env activate .
+          - spack env activate --without-view .
           - spack ci generate
             --output-file "${CI_PROJECT_DIR}/jobs_scratch_dir/pipeline.yml"
         artifacts:
@@ -82,9 +82,9 @@ or Amazon Elastic Kubernetes Service (`EKS <https://aws.amazon.com/eks>`_), thou
 topics are outside the scope of this document.
 
 Spack's pipelines are now making use of the
-`trigger <https://docs.gitlab.com/12.9/ee/ci/yaml/README.html#trigger>` syntax to run
+`trigger <https://docs.gitlab.com/12.9/ee/ci/yaml/README.html#trigger>`_ syntax to run
 dynamically generated
-`child pipelines <https://docs.gitlab.com/12.9/ee/ci/parent_child_pipelines.html>`.
+`child pipelines <https://docs.gitlab.com/12.9/ee/ci/parent_child_pipelines.html>`_.
 Note that the use of dynamic child pipelines requires running Gitlab version
 ``>= 12.9``.
 
@@ -122,6 +122,27 @@ pipeline jobs.
 Concretizes the specs in the active environment, stages them (as described in
 :ref:`staging_algorithm`), and writes the resulting ``.gitlab-ci.yml`` to disk.
 
+Using ``--prune-dag`` or ``--no-prune-dag`` configures whether or not jobs are
+generated for specs that are already up to date on the mirror.   If enabling
+DAG pruning using ``--prune-dag``, more information may be required in your
+``spack.yaml`` file, see the :ref:`noop_jobs` section below regarding
+``service-job-attributes``.
+
+The ``--optimize`` argument is experimental and runs the generated pipeline
+document through a series of optimization passes designed to reduce the size
+of the generated file.
+
+The ``--dependencies`` is also experimental and disables what in Gitlab is
+referred to as DAG scheduling, internally using the ``dependencies`` keyword
+rather than ``needs`` to list dependency jobs.  The drawback of using this option
+is that before any job can begin, all jobs in previous stages must first
+complete.  The benefit is that Gitlab allows more dependencies to be listed
+when using ``dependencies`` instead of ``needs``.
+
+The optional ``--output-file`` argument should be an absolute path (including
+file name) to the generated pipeline, and if not given, the default is
+``./.gitlab-ci.yml``.
+
 .. _cmd-spack-ci-rebuild:
 
 ^^^^^^^^^^^^^^^^^^^^
@@ -132,6 +153,10 @@ This sub-command is responsible for ensuring a single spec from the release
 environment is up to date on the remote mirror configured in the environment,
 and as such, corresponds to a single job in the ``.gitlab-ci.yml`` file.
 
+Rather than taking command-line arguments, this sub-command expects information
+to be communicated via environment variables, which will typically come via the
+``.gitlab-ci.yml`` job as ``variables``.
+
 ------------------------------------
 A pipeline-enabled spack environment
 ------------------------------------
@@ -189,28 +214,31 @@ corresponds to a known gitlab runner, where the ``match`` section is used
 in assigning a release spec to one of the runners, and the ``runner-attributes``
 section is used to configure the spec/job for that particular runner.
 
+Both the top-level ``gitlab-ci`` section as well as each ``runner-attributes``
+section can also contain the following keys: ``image``, ``tags``, ``variables``,
+``before_script``, ``script``, and ``after_script``.  If any of these keys are
+provided at the ``gitlab-ci`` level, they will be used as the defaults for any
+``runner-attributes``, unless they are overridden in those sections.  Specifying
+any of these keys at the ``runner-attributes`` level generally overrides the
+keys specified at the higher level, with a couple exceptions.  Any ``variables``
+specified at both levels result in those dictionaries getting merged in the
+resulting generated job, and any duplicate variable names get assigned the value
+provided in the specific ``runner-attributes``.  If ``tags`` are specified both
+at the ``gitlab-ci`` level as well as the ``runner-attributes`` level, then the
+lists of tags are combined, and any duplicates are removed.
+
+See the section below on using a custom spack for an example of how these keys
+could be used.
+
 There are other pipeline options you can configure within the ``gitlab-ci`` section
-as well.  The ``bootstrap`` section allows you to specify lists of specs from
+as well.
+
+The ``bootstrap`` section allows you to specify lists of specs from
 your ``definitions`` that should be staged ahead of the environment's ``specs`` (this
 section is described in more detail below).  The ``enable-artifacts-buildcache`` key
 takes a boolean and determines whether the pipeline uses artifacts to store and
 pass along the buildcaches from one stage to the next (the default if you don't
-provide this option is ``False``).  The ``enable-debug-messages`` key takes a boolean
-and allows you to choose whether the pipeline build jobs are run as ``spack -d ci rebuild``
-or just ``spack ci rebuild`` (the default is not to enable debug messages).  The
-``final-stage-rebuild-index`` section controls whether an extra job is added to the
-end of your pipeline (in a stage by itself) which will regenerate the mirror's
-buildcache index.  Under normal operation, each pipeline job that rebuilds a package
-will re-generate the mirror's buildcache index after the buildcache entry for that
-job has been created and pushed to the mirror.  Since jobs in the same stage can run in
-parallel, there is the possibility that at the end of some stage, the index may not
-reflect all the binaries in the buildcache.  Adding the ``final-stage-rebuild-index``
-section ensures that at the end of the pipeline, the index will be in sync with the
-binaries on the mirror.  If the mirror lives in an S3 bucket, this job will need to
-run on a machine with the Python ``boto3`` module installed, and consequently the
-``final-stage-rebuild-index`` needs to specify a list of ``tags`` to pick a runner
-satisfying that condition.  It can also take an ``image`` key so Docker executor type
-runners can pick the right image for the index regeneration job.
+provide this option is ``False``).
 
 The optional ``cdash`` section provides information that will be used by the
 ``spack ci generate`` command (invoked by ``spack ci start``) for reporting
@@ -220,6 +248,81 @@ progresses, this build group may have jobs added or removed. The url, project,
 and site are used to specify the CDash instance to which build results should
 be reported.
 
+Take a look at the
+`schema <https://github.com/spack/spack/blob/develop/lib/spack/spack/schema/gitlab_ci.py>`_
+for the gitlab-ci section of the spack environment file, to see precisely what
+syntax is allowed there.
+
+.. _rebuild_index:
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Note about rebuilding buildcache index
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+By default, while a pipeline job may rebuild a package, create a buildcache
+entry, and push it to the mirror, it does not automatically re-generate the
+mirror's buildcache index afterward.  Because the index is not needed by the
+default rebuild jobs in the pipeline, not updating the index at the end of
+each job avoids possible race conditions between simultaneous jobs, and it
+avoids the computational expense of regenerating the index.  This potentially
+saves minutes per job, depending on the number of binary packages in the
+mirror.  As a result, the default is that the mirror's buildcache index may
+not correctly reflect the mirror's contents at the end of a pipeline.
+
+To make sure the buildcache index is up to date at the end of your pipeline,
+spack generates a job to update the buildcache index of the target mirror
+at the end of each pipeline by default.  You can disable this behavior by
+adding ``rebuild-index: False`` inside the ``gitlab-ci`` section of your
+spack environment.  Spack will assign the job any runner attributes found
+on the ``service-job-attributes``, if you have provided that in your
+``spack.yaml``.
+
+.. _noop_jobs:
+
+^^^^^^^^^^^^^^^^^^^^^^^
+Note about "no-op" jobs
+^^^^^^^^^^^^^^^^^^^^^^^
+
+If no specs in an environment need to be rebuilt during a given pipeline run
+(meaning all are already up to date on the mirror), a single succesful job
+(a NO-OP) is still generated to avoid an empty pipeline (which GitLab
+considers to be an error).  An optional ``service-job-attributes`` section
+can be added to your ``spack.yaml`` where you can provide ``tags`` and
+``image`` or ``variables`` for the generated NO-OP job.  This section also
+supports providing ``before_script``, ``script``, and ``after_script``, in
+case you want to take some custom actions in the case of any empty pipeline.
+
+Following is an example of this section added to a ``spack.yaml``:
+
+.. code-block:: yaml
+
+   spack:
+     specs:
+       - openmpi
+     mirrors:
+       cloud_gitlab: https://mirror.spack.io
+     gitlab-ci:
+       mappings:
+         - match:
+             - os=centos8
+           runner-attributes:
+             tags:
+               - custom
+               - tag
+             image: spack/centos7
+       service-job-attributes:
+         tags: ['custom', 'tag']
+         image:
+           name: 'some.image.registry/custom-image:latest'
+           entrypoint: ['/bin/bash']
+         script:
+           - echo "Custom message in a custom script"
+
+The example above illustrates how you can provide the attributes used to run
+the NO-OP job in the case of an empty pipeline.  The only field for the NO-OP
+job that might be generated for you is ``script``, but that will only happen
+if you do not provide one yourself.
+
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Assignment of specs to runners
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -245,7 +348,18 @@ runners known to the gitlab instance.  For Docker executor type runners, the
 as well as an ``entrypoint`` to override whatever the default for that image is).
 For other types of runners the ``variables`` key will be useful to pass any
 information on to the runner that it needs to do its work (e.g. scheduler
-parameters, etc.).
+parameters, etc.).  Any ``variables`` provided here will be added, verbatim, to
+each job.
+
+The ``runner-attributes`` section also allows users to supply custom ``script``,
+``before_script``, and ``after_script`` sections to be applied to every job
+scheduled on that runner.  This allows users to do any custom preparation or
+cleanup tasks that fit their particular workflow, as well as completely
+customize the rebuilding of a spec if they so choose.  Spack will not generate
+a ``before_script`` or ``after_script`` for jobs, but if you do not provide
+a custom ``script``, spack will generate one for you that assumes your
+``spack.yaml`` is at the root of the repository, activates that environment for
+you, and invokes ``spack ci rebuild``.
 
 .. _staging_algorithm:
 
@@ -256,8 +370,8 @@ Summary of ``.gitlab-ci.yml`` generation algorithm
 All specs yielded by the matrix (or all the specs in the environment) have their
 dependencies computed, and the entire resulting set of specs are staged together
 before being run through the ``gitlab-ci/mappings`` entries, where each staged
-spec is assigned a runner.  "Staging" is the name we have given to the process
-of figuring out in what order the specs should be built, taking into consideration
+spec is assigned a runner.  "Staging" is the name given to the process of
+figuring out in what order the specs should be built, taking into consideration
 Gitlab CI rules about jobs/stages.  In the staging process the goal is to maximize
 the number of jobs in any stage of the pipeline, while ensuring that the jobs in
 any stage only depend on jobs in previous stages (since those jobs are guaranteed
@@ -268,7 +382,7 @@ a runner, the ``.gitlab-ci.yml`` is written to disk.
 
 The short example provided above would result in the ``readline``, ``ncurses``,
 and ``pkgconf`` packages getting staged and built on the runner chosen by the
-``spack-k8s`` tag.  In this example, we assume the runner is a Docker executor
+``spack-k8s`` tag.  In this example, spack assumes the runner is a Docker executor
 type runner, and thus certain jobs will be run in the ``centos7`` container,
 and others in the ``ubuntu-18.04`` container.  The resulting ``.gitlab-ci.yml``
 will contain 6 jobs in three stages.  Once the jobs have been generated, the
@@ -327,12 +441,12 @@ Here's an example of what bootstrapping some compilers might look like:
          # mappings similar to the example higher up in this description
          ...
 
-In the example above, we have added a list to the ``definitions`` called
-``compiler-pkgs`` (you can add any number of these), which lists compiler packages
-we want to be staged ahead of the full matrix of release specs (which consists
-only of readline in our example).  Then within the ``gitlab-ci`` section, we
-have added a ``bootstrap`` section, which can contain a list of items, each
-referring to a list in the ``definitions`` section.  These items can either
+The example above adds a list to the ``definitions`` called ``compiler-pkgs``
+(you can add any number of these), which lists compiler packages that should
+be staged ahead of the full matrix of release specs (in this example, only
+readline).  Then within the ``gitlab-ci`` section, note the addition of a
+``bootstrap`` section, which can contain a list of items, each referring to
+a list in the ``definitions`` section.  These items can either
 be a dictionary or a string.  If you supply a dictionary, it must have a name
 key whose value must match one of the lists in definitions and it can have a
 ``compiler-agnostic`` key whose value is a boolean.  If you supply a string,
@@ -368,13 +482,15 @@ Using a custom spack in your pipeline
 
 If your runners will not have a version of spack ready to invoke, or if for some
 other reason you want to use a custom version of spack to run your pipelines,
-this can be accomplished fairly simply.  First, create CI environment variables
-containing the url and branch/tag you want to clone (calling them, for example,
-``SPACK_REPO`` and ``SPACK_REF``), use them to clone spack in your pre-ci
-``before_script``, and finally pass those same values along to the workload
-generation process via the ``spack-repo`` and ``spack-ref`` cli args.  Here's
-the ``generate-pipeline`` job from the top of this document, updated to clone
-a custom spack and make sure the generated rebuild jobs will clone it too:
+this section provides an example of how you could take advantage of
+user-provided pipeline scripts to accomplish this fairly simply.  First, you
+could use the GitLab user interface to create CI environment variables
+containing the url and branch or tag you want to use (calling them, for
+example, ``SPACK_REPO`` and ``SPACK_REF``), then refer to those in a custom shell
+script invoked both from your pipeline generation job, as well as in your rebuild
+jobs.  Here's the ``generate-pipeline`` job from the top of this document,
+updated to invoke a custom shell script that will clone and source a custom
+spack:
 
 .. code-block:: yaml
 
@@ -382,12 +498,10 @@ a custom spack and make sure the generated rebuild jobs will clone it too:
      tags:
        - <some-other-tag>
    before_script:
-     - git clone ${SPACK_REPO} --branch ${SPACK_REF}
-     - . ./spack/share/spack/setup-env.sh
+     - ./cloneSpack.sh
    script:
-     - spack env activate .
+     - spack env activate --without-view .
      - spack ci generate
-       --spack-repo ${SPACK_REPO} --spack-ref ${SPACK_REF}
        --output-file "${CI_PROJECT_DIR}/jobs_scratch_dir/pipeline.yml"
    after_script:
      - rm -rf ./spack
@@ -395,13 +509,68 @@ a custom spack and make sure the generated rebuild jobs will clone it too:
      paths:
        - "${CI_PROJECT_DIR}/jobs_scratch_dir/pipeline.yml"
 
+And the ``cloneSpack.sh`` script could contain:
 
-If the ``spack ci generate`` command receives those extra command line arguments,
-then it adds similar ``before_script`` and ``after_script`` sections for each of
-the ``spack ci rebuild`` jobs it generates (cloning and sourcing a custom
-spack in the ``before_script`` and removing it again in the ``after_script``).
-This gives you control over the version of spack used when the rebuild jobs
-are actually run on the gitlab runner.
+.. code-block:: bash
+
+   #!/bin/bash
+
+   git clone ${SPACK_REPO}
+   pushd ./spack
+   git checkout ${SPACK_REF}
+   popd
+
+   . "./spack/share/spack/setup-env.sh"
+
+   spack --version
+
+Finally, you would also want your generated rebuild jobs to clone that version
+of spack, so you would update your ``spack.yaml`` from above as follows:
+
+.. code-block:: yaml
+
+   spack:
+     ...
+     gitlab-ci:
+       mappings:
+         - match:
+             - os=ubuntu18.04
+           runner-attributes:
+             tags:
+               - spack-kube
+             image: spack/ubuntu-bionic
+             before_script:
+               - ./cloneSpack.sh
+             script:
+               - spack env activate --without-view .
+               - spack -d ci rebuild
+             after_script:
+               - rm -rf ./spack
+
+Now all of the generated rebuild jobs will use the same shell script to clone
+spack before running their actual workload.  Note in the above example the
+provision of a custom ``script`` section.  The reason for this is to run
+``spack ci rebuild`` in debug mode to get more information when builds fail.
+
+Now imagine you have long pipelines with many specs to be built, and you
+are pointing to a spack repository and branch that has a tendency to change
+frequently, such as the main repo and it's ``develop`` branch.  If each child
+job checks out the ``develop`` branch, that could result in some jobs running
+with one SHA of spack, while later jobs run with another.  To help avoid this
+issue, the pipeline generation process saves global variables called
+``SPACK_VERSION`` and ``SPACK_CHECKOUT_VERSION`` that capture the version
+of spack used to generate the pipeline.  While the ``SPACK_VERSION`` variable
+simply contains the human-readable value produced by ``spack -V`` at pipeline
+generation time, the ``SPACK_CHECKOUT_VERSION`` variable can be used in a
+``git checkout`` command to make sure all child jobs checkout the same version
+of spack used to generate the pipeline.  To take advantage of this, you could
+simply replace ``git checkout ${SPACK_REF}`` in the example ``cloneSpack.sh``
+script above with ``git checkout ${SPACK_CHECKOUT_VERSION}``.
+
+On the other hand, if you're pointing to a spack repository and branch under your
+control, there may be no benefit in using the captured ``SPACK_CHECKOUT_VERSION``,
+and you can instead just clone using the project CI variables you set (in the
+earlier example these were ``SPACK_REPO`` and ``SPACK_REF``).
 
 .. _ci_environment_variables:
 

lib/spack/docs/repositories.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -9,7 +9,7 @@
 Package Repositories
 =============================
 
-Spack comes with over 1,000 built-in package recipes in
+Spack comes with thousands of built-in package recipes in
 ``var/spack/repos/builtin/``.  This is a **package repository** -- a
 directory that Spack searches when it needs to find a package by name.
 You may need to maintain packages for restricted, proprietary or

lib/spack/docs/spack.yaml

@@ -1,4 +1,4 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/docs/workflows.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
    Spack Project Developers. See the top-level COPYRIGHT file for details.
 
    SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -703,400 +703,6 @@ environments:
   Administrators might find things easier to maintain without the
   added "heavyweight" state of a view.
 
-------------------------------
-Developing Software with Spack
-------------------------------
-
-For any project, one needs to assemble an
-environment of that application's dependencies.  You might consider
-loading a series of modules or creating a filesystem view.  This
-approach, while obvious, has some serious drawbacks:
-
-1. There is no guarantee that an environment created this way will be
-   consistent.  Your application could end up with dependency A
-   expecting one version of MPI, and dependency B expecting another.
-   The linker will not be happy...
-
-2. Suppose you need to debug a package deep within your software DAG.
-   If you build that package with a manual environment, then it
-   becomes difficult to have Spack auto-build things that depend on
-   it.  That could be a serious problem, depending on how deep the
-   package in question is in your dependency DAG.
-
-3. At its core, Spack is a sophisticated concretization algorithm that
-   matches up packages with appropriate dependencies and creates a
-   *consistent* environment for the package it's building.  Writing a
-   list of ``spack load`` commands for your dependencies is at least
-   as hard as writing the same list of ``depends_on()`` declarations
-   in a Spack package.  But it makes no use of Spack concretization
-   and is more error-prone.
-
-4. Spack provides an automated, systematic way not just to find a
-   packages's dependencies --- but also to build other packages on
-   top.  Any Spack package can become a dependency for another Spack
-   package, offering a powerful vision of software re-use.  If you
-   build your package A outside of Spack, then your ability to use it
-   as a building block for other packages in an automated way is
-   diminished: other packages depending on package A will not
-   be able to use Spack to fulfill that dependency.
-
-5. If you are reading this manual, you probably love Spack.  You're
-   probably going to write a Spack package for your software so
-   prospective users can install it with the least amount of pain.
-   Why should you go to additional work to find dependencies in your
-   development environment?  Shouldn't Spack be able to help you build
-   your software based on the package you've already written?
-
-In this section, we show how Spack can be used in the software
-development process to greatest effect, and how development packages
-can be seamlessly integrated into the Spack ecosystem.  We will show
-how this process works by example, assuming the software you are
-creating is called ``mylib``.
-
-^^^^^^^^^^^^^^^^^^^^^
-Write the CMake Build
-^^^^^^^^^^^^^^^^^^^^^
-
-For now, the techniques in this section only work for CMake-based
-projects, although they could be easily extended to other build
-systems in the future.  We will therefore assume you are using CMake
-to build your project.
-
-The ``CMakeLists.txt`` file should be written as normal.  A few caveats:
-
-1. Your project should produce binaries with RPATHs.  This will ensure
-   that they work the same whether built manually or automatically by
-   Spack.  For example:
-
-.. code-block:: cmake
-
-   # enable @rpath in the install name for any shared library being built
-   # note: it is planned that a future version of CMake will enable this by default
-   set(CMAKE_MACOSX_RPATH 1)
-
-   # Always use full RPATH
-   # http://www.cmake.org/Wiki/CMake_RPATH_handling
-   # http://www.kitware.com/blog/home/post/510
-
-   # use, i.e. don't skip the full RPATH for the build tree
-   SET(CMAKE_SKIP_BUILD_RPATH  FALSE)
-
-   # when building, don't use the install RPATH already
-   # (but later on when installing)
-   SET(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE)
-
-   # add the automatically determined parts of the RPATH
-   # which point to directories outside the build tree to the install RPATH
-   SET(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
-
-   # the RPATH to be used when installing, but only if it's not a system directory
-   LIST(FIND CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES "${CMAKE_INSTALL_PREFIX}/lib" isSystemDir)
-   IF("${isSystemDir}" STREQUAL "-1")
-      SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
-   ENDIF("${isSystemDir}" STREQUAL "-1")
-
-
-2. Spack provides a CMake variable called
-   ``SPACK_TRANSITIVE_INCLUDE_PATH``, which contains the ``include/``
-   directory for all of your project's transitive dependencies.  It
-   can be useful if your project ``#include``s files from package B,
-   which ``#include`` files from package C, but your project only
-   lists project B as a dependency.  This works in traditional
-   single-tree build environments, in which B and C's include files
-   live in the same place.  In order to make it work with Spack as
-   well, you must add the following to ``CMakeLists.txt``.  It will
-   have no effect when building without Spack:
-
-   .. code-block:: cmake
-
-      # Include all the transitive dependencies determined by Spack.
-      # If we're not running with Spack, this does nothing...
-      include_directories($ENV{SPACK_TRANSITIVE_INCLUDE_PATH})
-
-   .. note::
-
-      Note that this feature is controversial and could break with
-      future versions of GNU ld.  The best practice is to make sure
-      anything you ``#include`` is listed as a dependency in your
-      CMakeLists.txt (and Spack package).
-
-.. _write-the-spack-package:
-
-^^^^^^^^^^^^^^^^^^^^^^^
-Write the Spack Package
-^^^^^^^^^^^^^^^^^^^^^^^
-
-The Spack package also needs to be written, in tandem with setting up
-the build (for example, CMake).  The most important part of this task
-is declaring dependencies.  Here is an example of the Spack package
-for the ``mylib`` package (ellipses for brevity):
-
-.. code-block:: python
-
-   class Mylib(CMakePackage):
-       """Misc. reusable utilities used by Myapp."""
-
-       homepage = "https://github.com/citibeth/mylib"
-       url = "https://github.com/citibeth/mylib/tarball/123"
-
-       version('0.1.2', '3a6acd70085e25f81b63a7e96c504ef9')
-       version('develop', git='https://github.com/citibeth/mylib.git',
-           branch='develop')
-
-       variant('everytrace', default=False,
-               description='Report errors through Everytrace')
-       ...
-
-       extends('python')
-
-       depends_on('eigen')
-       depends_on('everytrace', when='+everytrace')
-       depends_on('proj', when='+proj')
-       ...
-       depends_on('cmake', type='build')
-       depends_on('doxygen', type='build')
-
-       def cmake_args(self):
-           spec = self.spec
-           return [
-               '-DUSE_EVERYTRACE=%s' % ('YES' if '+everytrace' in spec else 'NO'),
-               '-DUSE_PROJ4=%s' % ('YES' if '+proj' in spec else 'NO'),
-               ...
-               '-DUSE_UDUNITS2=%s' % ('YES' if '+udunits2' in spec else 'NO'),
-               '-DUSE_GTEST=%s' % ('YES' if '+googletest' in spec else 'NO')]
-
-This is a standard Spack package that can be used to install
-``mylib`` in a production environment.  The list of dependencies in
-the Spack package will generally be a repeat of the list of CMake
-dependencies.  This package also has some features that allow it to be
-used for development:
-
-1. It subclasses ``CMakePackage`` instead of ``Package``.  This
-   eliminates the need to write an ``install()`` method, which is
-   defined in the superclass.  Instead, one just needs to write the
-   ``configure_args()`` method.  That method should return the
-   arguments needed for the ``cmake`` command (beyond the standard
-   CMake arguments, which Spack will include already).  These
-   arguments are typically used to turn features on/off in the build.
-
-2. It specifies a non-checksummed version ``develop``.  Running
-   ``spack install mylib@develop`` the ``@develop`` version will
-   install the latest version off the develop branch.  This method of
-   download is useful for the developer of a project while it is in
-   active development; however, it should only be used by developers
-   who control and trust the repository in question!
-
-3. The ``url``, ``url_for_version()`` and ``homepage`` attributes are
-   not used in development.  Don't worry if you don't have any, or if
-   they are behind a firewall.
-
-^^^^^^^^^^^^^^^^
-Build with Spack
-^^^^^^^^^^^^^^^^
-
-Now that you have a Spack package, you can use Spack to find its
-dependencies automatically.  For example:
-
-.. code-block:: console
-
-   $ cd mylib
-   $ spack setup mylib@local
-
-The result will be a file ``spconfig.py`` in the top-level
-``mylib/`` directory.  It is a short script that calls CMake with the
-dependencies and options determined by Spack --- similar to what
-happens in ``spack install``, but now written out in script form.
-From a developer's point of view, you can think of ``spconfig.py`` as
-a stand-in for the ``cmake`` command.
-
-.. note::
-
-   You can invent any "version" you like for the ``spack setup``
-   command.
-
-.. note::
-
-   Although ``spack setup`` does not build your package, it does
-   create and install a module file, and mark in the database that
-   your package has been installed.  This can lead to errors, of
-   course, if you don't subsequently install your package.
-   Also... you will need to ``spack uninstall`` before you run
-   ``spack setup`` again.
-
-
-You can now build your project as usual with CMake:
-
-.. code-block:: console
-
-   $ mkdir build; cd build
-   $ ../spconfig.py ..   # Instead of cmake ..
-   $ make
-   $ make install
-
-Once your ``make install`` command is complete, your package will be
-installed, just as if you'd run ``spack install``.  Except you can now
-edit, re-build and re-install as often as needed, without checking
-into Git or downloading tarballs.
-
-.. note::
-
-   The build you get this way will be *almost* the same as the build
-   from ``spack install``.  The only difference is, you will not be
-   using Spack's compiler wrappers.  This difference has not caused
-   problems in our experience, as long as your project sets
-   RPATHs as shown above.  You DO use RPATHs, right?
-
-^^^^^^^^^^^^^^^^^^^^
-Build Other Software
-^^^^^^^^^^^^^^^^^^^^
-
-Now that you've built ``mylib`` with Spack, you might want to build
-another package that depends on it --- for example, ``myapp``.  This
-is accomplished easily enough:
-
-.. code-block:: console
-
-   $ spack install myapp ^mylib@local
-
-Note that auto-built software has now been installed *on top of*
-manually-built software, without breaking Spack's "web."  This
-property is useful if you need to debug a package deep in the
-dependency hierarchy of your application.  It is a *big* advantage of
-using ``spack setup`` to build your package's environment.
-
-If you feel your software is stable, you might wish to install it with
-``spack install`` and skip the source directory.  You can just use,
-for example:
-
-.. code-block:: console
-
-   $ spack install mylib@develop
-
-.. _release-your-software:
-
-^^^^^^^^^^^^^^^^^^^^^
-Release Your Software
-^^^^^^^^^^^^^^^^^^^^^
-
-You are now ready to release your software as a tarball with a
-numbered version, and a Spack package that can build it.  If you're
-hosted on GitHub, this process will be a bit easier.
-
-#. Put tag(s) on the version(s) in your GitHub repo you want to be
-   release versions.  For example, a tag ``v0.1.0`` for version 0.1.0.
-
-#. Set the ``url`` in your ``package.py`` to download a tarball for
-   the appropriate version.  GitHub will give you a tarball for any
-   commit in the repo, if you tickle it the right way.  For example:
-
-   .. code-block:: python
-
-      url = 'https://github.com/citibeth/mylib/tarball/v0.1.2'
-
-#. Use Spack to determine your version's hash, and cut'n'paste it into
-   your ``package.py``:
-
-   .. code-block:: console
-
-      $ spack checksum mylib 0.1.2
-      ==> Found 1 versions of mylib
-        0.1.2     https://github.com/citibeth/mylib/tarball/v0.1.2
-
-      How many would you like to checksum? (default is 5, q to abort)
-      ==> Downloading...
-      ==> Trying to fetch from https://github.com/citibeth/mylib/tarball/v0.1.2
-      ######################################################################## 100.0%
-      ==> Checksummed new versions of mylib:
-            version('0.1.2', '3a6acd70085e25f81b63a7e96c504ef9')
-
-#. You should now be able to install released version 0.1.2 of your package with:
-
-   .. code-block:: console
-
-      $ spack install mylib@0.1.2
-
-#. There is no need to remove the `develop` version from your package.
-   Spack concretization will always prefer numbered version to
-   non-numeric versions.  Users will only get it if they ask for it.
-
-^^^^^^^^^^^^^^^^^^^^^^^^
-Distribute Your Software
-^^^^^^^^^^^^^^^^^^^^^^^^
-
-Once you've released your software, other people will want to build
-it; and you will need to tell them how.  In the past, that has meant a
-few paragraphs of prose explaining which dependencies to install.  But
-now you use Spack, and those instructions are written in executable
-Python code.  But your software has many dependencies, and you know
-Spack is the best way to install it:
-
-#. First, you will want to fork Spack's ``develop`` branch.  Your aim
-   is to provide a stable version of Spack that you KNOW will install
-   your software.  If you make changes to Spack in the process, you
-   will want to submit pull requests to Spack core.
-
-#. Add your software's ``package.py`` to that fork.  You should submit
-   a pull request for this as well, unless you don't want the public
-   to know about your software.
-
-#. Prepare instructions that read approximately as follows:
-
-   #. Download Spack from your forked repo.
-
-   #. Install Spack; see :ref:`getting_started`.
-
-   #. Set up an appropriate ``packages.yaml`` file.  You should tell
-      your users to include in this file whatever versions/variants
-      are needed to make your software work correctly (assuming those
-      are not already in your ``packages.yaml``).
-
-   #. Run ``spack install mylib``.
-
-   #. Run this script to generate the ``module load`` commands or
-      filesystem view needed to use this software.
-
-#. Be aware that your users might encounter unexpected bootstrapping
-   issues on their machines, especially if they are running on older
-   systems.  The :ref:`getting_started` section should cover this, but
-   there could always be issues.
-
-^^^^^^^^^^^^^^^^^^^
-Other Build Systems
-^^^^^^^^^^^^^^^^^^^
-
-``spack setup`` currently only supports CMake-based builds, in
-packages that subclass ``CMakePackage``.  The intent is that this
-mechanism should support a wider range of build systems; for example,
-GNU Autotools.  Someone well-versed in Autotools is needed to develop
-this patch and test it out.
-
-Python Distutils is another popular build system that should get
-``spack setup`` support.  For non-compiled languages like Python,
-``spack diy`` may be used.  Even better is to put the source directory
-directly in the user's ``PYTHONPATH``.  Then, edits in source files
-are immediately available to run without any install process at all!
-
-^^^^^^^^^^
-Conclusion
-^^^^^^^^^^
-
-The ``spack setup`` development workflow provides better automation,
-flexibility and safety than workflows relying on environment modules
-or filesystem views.  However, it has some drawbacks:
-
-#. It currently works only with projects that use the CMake build
-   system.  Support for other build systems is not hard to build, but
-   will require a small amount of effort for each build system to be
-   supported.  It might not work well with some IDEs.
-
-#. It only works with packages that sub-class ``StagedPackage``.
-   Currently, most Spack packages do not.  Converting them is not
-   hard; but must be done on a package-by-package basis.
-
-#. It requires that users are comfortable with Spack, as they
-   integrate Spack explicitly in their workflow.  Not all users are
-   willing to do this.
-
 -------------------------------------
 Using Spack to Replace Homebrew/Conda
 -------------------------------------
@@ -1405,11 +1011,12 @@ The main points that are implemented below:
      - export CXXFLAGS="-std=c++11"
 
    install:
-     - if ! which spack >/dev/null; then
+     - |
+       if ! which spack >/dev/null; then
          mkdir -p $SPACK_ROOT &&
          git clone --depth 50 https://github.com/spack/spack.git $SPACK_ROOT &&
-         echo -e "config:""\n  build_jobs:"" 2" > $SPACK_ROOT/etc/spack/config.yaml **
-         echo -e "packages:""\n  all:""\n    target:"" ['x86_64']"
+         printf "config:\n  build_jobs: 2\n" > $SPACK_ROOT/etc/spack/config.yaml &&
+         printf "packages:\n  all:\n    target: ['x86_64']\n" \
                  > $SPACK_ROOT/etc/spack/packages.yaml;
        fi
      - travis_wait spack install cmake@3.7.2~openssl~ncurses
@@ -1427,170 +1034,6 @@ The main points that are implemented below:
      - make -j 2
      - make test
 
-.. _workflow_create_docker_image:
-
------------------------------------
-Using Spack to Create Docker Images
------------------------------------
-
-Spack can be the ideal tool to set up images for Docker (and Singularity).
-
-An example ``Dockerfile`` is given below, downloading the latest spack
-version.
-
-The following functionality is prepared:
-
-#. Base image: the example starts from a minimal ubuntu.
-
-#. Pre-install the spack dependencies.
-   Package installs are followed by a clean-up of the system package index,
-   to avoid outdated information and it saves space.
-
-#. Install spack in ``/usr/local``.
-   Add ``setup-env.sh`` to profile scripts, so commands in *login* shells
-   can use the whole spack functionality, including modules.
-
-#. Install an example package (``tar``).
-   As with system package managers above, ``spack install`` commands should be
-   concatenated with a ``&& spack clean -a`` in order to keep image sizes small.
-
-#. Add a startup hook to an *interactive login shell* so spack modules will be
-   usable.
-
-In order to build and run the image, execute:
-
-.. code-block:: bash
-
-   docker build -t spack .
-   docker run -it spack
-
-.. code-block:: docker
-
-   FROM       ubuntu:16.04
-   MAINTAINER Your Name <someone@example.com>
-
-   # general environment for docker
-   ENV        DEBIAN_FRONTEND=noninteractive \
-              SPACK_ROOT=/usr/local
-
-   # install minimal spack dependencies
-   RUN        apt-get update \
-              && apt-get install -y --no-install-recommends \
-                 autoconf \
-                 build-essential \
-                 ca-certificates \
-                 coreutils \
-                 curl \
-                 environment-modules \
-                 git \
-                 python \
-                 unzip \
-                 vim \
-              && rm -rf /var/lib/apt/lists/*
-
-   # load spack environment on login
-   RUN        echo "source $SPACK_ROOT/share/spack/setup-env.sh" \
-              > /etc/profile.d/spack.sh
-
-   # spack settings
-   # note: if you wish to change default settings, add files alongside
-   #       the Dockerfile with your desired settings. Then uncomment this line
-   #COPY       packages.yaml modules.yaml $SPACK_ROOT/etc/spack/
-
-   # install spack
-   RUN        curl -s -L https://api.github.com/repos/spack/spack/tarball \
-              | tar xzC $SPACK_ROOT --strip 1
-   # note: at this point one could also run ``spack bootstrap`` to avoid
-   #       parts of the long apt-get install list above
-
-   # install software
-   RUN        spack install tar \
-              && spack clean -a
-
-   # need the executables from a package already during image build?
-   #RUN        /bin/bash -l -c ' \
-   #                spack load tar \
-   #                && which tar'
-
-   # image run hook: the -l will make sure /etc/profile environments are loaded
-   CMD        /bin/bash -l
-
-^^^^^^^^^^^^^^
-Best Practices
-^^^^^^^^^^^^^^
-
-"""
-MPI
-"""
-Due to the dependency on Fortran for OpenMPI, which is the spack default
-implementation, consider adding ``gfortran`` to the ``apt-get install`` list.
-
-Recent versions of OpenMPI will require you to pass ``--allow-run-as-root``
-to your ``mpirun`` calls if started as root user inside Docker.
-
-For execution on HPC clusters, it can be helpful to import the docker
-image into Singularity in order to start a program with an *external*
-MPI. Otherwise, also add ``openssh-server`` to the ``apt-get install`` list.
-
-""""
-CUDA
-""""
-Starting from CUDA 9.0, Nvidia provides minimal CUDA images based on
-Ubuntu.
-Please see `their instructions <https://hub.docker.com/r/nvidia/cuda/>`_.
-Avoid double-installing CUDA by adding, e.g.
-
-.. code-block:: yaml
-
-   packages:
-     cuda:
-       paths:
-         cuda@9.0.176%gcc@5.4.0 arch=linux-ubuntu16-x86_64: /usr/local/cuda
-       buildable: False
-
-to your ``packages.yaml``.
-Then ``COPY`` in that file into the image as in the example above.
-
-Users will either need ``nvidia-docker`` or e.g. Singularity to *execute*
-device kernels.
-
-"""""""""""
-Singularity
-"""""""""""
-Importing and running the image created above into
-`Singularity <http://singularity.lbl.gov/>`_ works like a charm.
-Just use the `docker bootstraping mechanism <http://singularity.lbl.gov/quickstart#bootstrap-recipes>`_:
-
-.. code-block:: none
-
-   Bootstrap: docker
-   From: registry/user/image:tag
-
-   %runscript
-   exec /bin/bash -l
-
-""""""""""""""""""""""
-Docker for Development
-""""""""""""""""""""""
-
-For examples of how we use docker in development, see
-:ref:`docker_for_developers`.
-
-"""""""""""""""""""""""""
-Docker on Windows and OSX
-"""""""""""""""""""""""""
-
-On Mac OS and Windows, docker runs on a hypervisor that is not allocated much
-memory by default, and some spack packages may fail to build due to lack of
-memory. To work around this issue, consider configuring your docker installation
-to use more of your host memory. In some cases, you can also ease the memory
-pressure on parallel builds by limiting the parallelism in your config.yaml.
-
-.. code-block:: yaml
-
-   config:
-     build_jobs: 2
-
 ------------------
 Upstream Bug Fixes
 ------------------

lib/spack/env/aocc/clang

@@ -0,0 +1 @@
+../cc

lib/spack/env/aocc/clang++

@@ -0,0 +1 @@
+../cpp

lib/spack/env/aocc/flang

@@ -0,0 +1 @@
+../fc

lib/spack/env/cc

@@ -1,6 +1,6 @@
 #!/bin/bash
 #
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -22,7 +22,7 @@
 
 # This is an array of environment variables that need to be set before
 # the script runs. They are set by routines in spack.build_environment
-# as part of spack.package.Package.do_install().
+# as part of the package installation process.
 parameters=(
     SPACK_ENV_PATH
     SPACK_DEBUG_LOG_DIR
@@ -107,25 +107,25 @@ case "$command" in
     cpp)
         mode=cpp
         ;;
-    cc|c89|c99|gcc|clang|armclang|icc|pgcc|xlc|xlc_r|fcc)
+    cc|c89|c99|gcc|clang|armclang|icc|icx|pgcc|nvc|xlc|xlc_r|fcc)
         command="$SPACK_CC"
         language="C"
         comp="CC"
         lang_flags=C
         ;;
-    c++|CC|g++|clang++|armclang++|icpc|pgc++|xlc++|xlc++_r|FCC)
+    c++|CC|g++|clang++|armclang++|icpc|icpx|pgc++|nvc++|xlc++|xlc++_r|FCC)
         command="$SPACK_CXX"
         language="C++"
         comp="CXX"
         lang_flags=CXX
         ;;
-    ftn|f90|fc|f95|gfortran|flang|armflang|ifort|pgfortran|xlf90|xlf90_r|nagfor|frt)
+    ftn|f90|fc|f95|gfortran|flang|armflang|ifort|ifx|pgfortran|nvfortran|xlf90|xlf90_r|nagfor|frt)
         command="$SPACK_FC"
         language="Fortran 90"
         comp="FC"
         lang_flags=F
         ;;
-    f77|xlf|xlf_r|pgf77|frt)
+    f77|xlf|xlf_r|pgf77)
         command="$SPACK_F77"
         language="Fortran 77"
         comp="F77"
@@ -320,9 +320,13 @@ while [ -n "$1" ]; do
             if [ -z "$arg" ]; then shift; arg="$1"; fi
             if [[ "$arg" = -rpath=* ]]; then
                 rp="${arg#-rpath=}"
+            elif [[ "$arg" = --rpath=* ]]; then
+                rp="${arg#--rpath=}"
             elif [[ "$arg" = -rpath,* ]]; then
                 rp="${arg#-rpath,}"
-            elif [[ "$arg" = -rpath ]]; then
+            elif [[ "$arg" = --rpath,* ]]; then
+                rp="${arg#--rpath,}"
+            elif [[ "$arg" =~ ^-?-rpath$ ]]; then
                 shift; arg="$1"
                 if [[ "$arg" != -Wl,* ]]; then
                     die "-Wl,-rpath was not followed by -Wl,*"
@@ -339,7 +343,9 @@ while [ -n "$1" ]; do
             if [ -z "$arg" ]; then shift; arg="$1"; fi
             if [[ "$arg" = -rpath=* ]]; then
                 rp="${arg#-rpath=}"
-            elif [[ "$arg" = -rpath ]]; then
+            elif [[ "$arg" = --rpath=* ]]; then
+                rp="${arg#--rpath=}"
+            elif [[ "$arg" = -rpath  ]] || [[ "$arg" = --rpath ]]; then
                 shift; arg="$1"
                 if [[ "$arg" != -Xlinker,* ]]; then
                     die "-Xlinker,-rpath was not followed by -Xlinker,*"
@@ -434,7 +440,7 @@ then
         ld)
             flags=("${flags[@]}" -headerpad_max_install_names) ;;
         ccld)
-            flags=("${flags[@]}" -Wl,-headerpad_max_install_names) ;;
+            flags=("${flags[@]}" "-Wl,-headerpad_max_install_names") ;;
     esac
 fi
 
@@ -491,19 +497,19 @@ args+=("${flags[@]}")
 # Insert include directories just prior to any system include directories
 
 for dir in "${includes[@]}";         do args+=("-I$dir"); done
-for dir in "${isystem_includes[@]}";         do args+=("-isystem$dir"); done
+for dir in "${isystem_includes[@]}";         do args+=("-isystem" "$dir"); done
 
 IFS=':' read -ra spack_include_dirs <<< "$SPACK_INCLUDE_DIRS"
 if [[ $mode == cpp || $mode == cc || $mode == as || $mode == ccld ]]; then
     if [[ "$isystem_was_used" == "true" ]] ; then
-	for dir in "${spack_include_dirs[@]}";  do args+=("-isystem$dir"); done
+	for dir in "${spack_include_dirs[@]}";  do args+=("-isystem" "$dir"); done
     else
 	for dir in "${spack_include_dirs[@]}";  do args+=("-I$dir"); done
     fi
 fi
 
 for dir in "${system_includes[@]}";  do args+=("-I$dir"); done
-for dir in "${isystem_system_includes[@]}";  do args+=("-isystem$dir"); done
+for dir in "${isystem_system_includes[@]}";  do args+=("-isystem" "$dir"); done
 
 # Library search paths
 for dir in "${libdirs[@]}";          do args+=("-L$dir"); done
@@ -512,12 +518,12 @@ for dir in "${system_libdirs[@]}";   do args+=("-L$dir"); done
 # RPATHs arguments
 case "$mode" in
     ccld)
-        if [ ! -z "$dtags_to_add" ] ; then args+=("$linker_arg$dtags_to_add") ; fi
+        if [ -n "$dtags_to_add" ] ; then args+=("$linker_arg$dtags_to_add") ; fi
         for dir in "${rpaths[@]}";        do args+=("$rpath$dir"); done
         for dir in "${system_rpaths[@]}"; do args+=("$rpath$dir"); done
         ;;
     ld)
-        if [ ! -z "$dtags_to_add" ] ; then args+=("$dtags_to_add") ; fi
+        if [ -n "$dtags_to_add" ] ; then args+=("$dtags_to_add") ; fi
         for dir in "${rpaths[@]}";        do args+=("-rpath" "$dir"); done
         for dir in "${system_rpaths[@]}"; do args+=("-rpath" "$dir"); done
         ;;

lib/spack/env/nvhpc/nvc

@@ -0,0 +1 @@
+../cc

lib/spack/env/nvhpc/nvc++

@@ -0,0 +1 @@
+../cc

lib/spack/env/nvhpc/nvfortran

@@ -0,0 +1 @@
+../cc

lib/spack/env/oneapi/icpx

@@ -0,0 +1 @@
+../cc

lib/spack/env/oneapi/icx

@@ -0,0 +1 @@
+../cc

lib/spack/env/oneapi/ifx

@@ -0,0 +1 @@
+../cc

lib/spack/external/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
 # Spack Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
@@ -6,6 +6,13 @@
 """This module contains the following external, potentially separately
 licensed, packages that are included in Spack:
 
+archspec
+--------
+
+* Homepage: https://pypi.python.org/pypi/archspec
+* Usage: Labeling, comparison and detection of microarchitectures
+* Version: 0.1.2 (commit 068b0ebd641211971acf10f39aa876703a34bae4)
+
 argparse
 --------
 

lib/spack/external/_pytest/assertion/util.py

@@ -5,9 +5,12 @@
 import _pytest._code
 import py
 try:
-    from collections import Sequence
+    from collections.abc import Sequence
 except ImportError:
-    Sequence = list
+    try:
+        from collections import Sequence
+    except ImportError:
+        Sequence = list
 
 
 u = py.builtin._totext

lib/spack/external/_pytest/main.py

@@ -10,9 +10,12 @@
 import _pytest._code
 import py
 try:
-    from collections import MutableMapping as MappingMixin
+    from collections.abc import MutableMapping as MappingMixin
 except ImportError:
-    from UserDict import DictMixin as MappingMixin
+    try:
+        from collections import MutableMapping as MappingMixin
+    except ImportError:
+        from UserDict import DictMixin as MappingMixin
 
 from _pytest.config import directory_arg, UsageError, hookimpl
 from _pytest.outcomes import exit

lib/spack/external/_pytest/python_api.py

@@ -398,7 +398,10 @@ def approx(expected, rel=None, abs=None, nan_ok=False):
        __ https://docs.python.org/3/reference/datamodel.html#object.__ge__
     """
 
-    from collections import Mapping, Sequence
+    if sys.version_info >= (3, 3):
+        from collections.abc import Mapping, Sequence
+    else:
+        from collections import Mapping, Sequence
     from _pytest.compat import STRING_TYPES as String
 
     # Delegate the comparison to a class that knows how to deal with the type

lib/spack/external/archspec/COPYRIGHT

@@ -0,0 +1,22 @@
+Intellectual Property Notice
+------------------------------
+
+Archspec is licensed under the Apache License, Version 2.0 (LICENSE-APACHE
+or http://www.apache.org/licenses/LICENSE-2.0) or the MIT license,
+(LICENSE-MIT or http://opensource.org/licenses/MIT), at your option.
+
+Copyrights and patents in the Archspec project are retained by contributors.
+No copyright assignment is required to contribute to Archspec.
+
+
+SPDX usage
+------------
+
+Individual files contain SPDX tags instead of the full license text.
+This enables machine processing of license information based on the SPDX
+License Identifiers that are available here: https://spdx.org/licenses/
+
+Files that are dual-licensed as Apache-2.0 OR MIT contain the following
+text in the license header:
+
+    SPDX-License-Identifier: (Apache-2.0 OR MIT)

lib/spack/external/archspec/LICENSE-APACHE

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
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lib/spack/external/archspec/LICENSE-MIT

@@ -0,0 +1,20 @@
+Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+Archspec Project Developers. See the top-level COPYRIGHT file for details.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

lib/spack/external/archspec/README.md

@@ -0,0 +1,68 @@
+[![](https://github.com/archspec/archspec/workflows/Unit%20tests/badge.svg)](https://github.com/archspec/archspec/actions)
+[![codecov](https://codecov.io/gh/archspec/archspec/branch/master/graph/badge.svg)](https://codecov.io/gh/archspec/archspec)
+[![Documentation Status](https://readthedocs.org/projects/archspec/badge/?version=latest)](https://archspec.readthedocs.io/en/latest/?badge=latest)
+
+
+# Archspec (Python bindings)
+
+Archspec aims at providing a standard set of human-understandable labels for
+various aspects of a system architecture  like CPU, network fabrics, etc. and
+APIs to detect, query and compare them.
+
+This project grew out of [Spack](https://spack.io/) and is currently under
+active development. At present it supports APIs to detect and model
+compatibility relationships among different CPU microarchitectures.
+
+## Getting started with development
+
+The `archspec` Python package needs [poetry](https://python-poetry.org/) to
+be installed from VCS sources. The preferred method to install it is via
+its custom installer outside of any virtual environment:
+```console
+$ curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/get-poetry.py | python
+```
+You can refer to [Poetry's documentation](https://python-poetry.org/docs/#installation)
+for further details or for other methods to install this tool. You'll also need `tox`
+to run unit test:
+```console
+$ pip install --user tox
+```
+Finally you'll need to clone the repository:
+```console
+$ git clone --recursive https://github.com/archspec/archspec.git
+```
+
+### Running unit tests
+Once you have your environment ready you can run `archspec` unit tests
+using ``tox`` from the root of the repository:
+```console
+$ tox
+  [ ... ]
+  py27: commands succeeded
+  py35: commands succeeded
+  py36: commands succeeded
+  py37: commands succeeded
+  py38: commands succeeded
+  pylint: commands succeeded
+  flake8: commands succeeded
+  black: commands succeeded
+  congratulations :)
+```
+
+## License
+
+Archspec is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0). Users may choose either license, at their
+option.
+
+All new contributions must be made under both the MIT and Apache-2.0
+licenses.
+
+See [LICENSE-MIT](https://github.com/archspec/archspec/blob/master/LICENSE-MIT),
+[LICENSE-APACHE](https://github.com/archspec/archspec/blob/master/LICENSE-APACHE),
+[COPYRIGHT](https://github.com/archspec/archspec/blob/master/COPYRIGHT), and
+[NOTICE](https://github.com/archspec/archspec/blob/master/NOTICE) for details.
+
+SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+LLNL-CODE-811653

lib/spack/external/archspec/__init__.py

@@ -0,0 +1,2 @@
+"""Init file to avoid namespace packages"""
+__version__ = "0.1.2"

lib/spack/external/archspec/cli.py

@@ -0,0 +1,24 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""
+archspec command line interface
+"""
+
+import click
+
+import archspec
+import archspec.cpu
+
+
+@click.group(name="archspec")
+@click.version_option(version=archspec.__version__)
+def main():
+    """archspec command line interface"""
+
+
+@main.command()
+def cpu():
+    """archspec command line interface for CPU"""
+    click.echo(archspec.cpu.host())

lib/spack/external/archspec/cpu/__init__.py

@@ -0,0 +1,20 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""The "cpu" package permits to query and compare different
+CPU microarchitectures.
+"""
+from .microarchitecture import Microarchitecture, UnsupportedMicroarchitecture
+from .microarchitecture import TARGETS, generic_microarchitecture
+from .microarchitecture import version_components
+from .detect import host
+
+__all__ = [
+    "Microarchitecture",
+    "UnsupportedMicroarchitecture",
+    "TARGETS",
+    "generic_microarchitecture",
+    "host",
+    "version_components",
+]

lib/spack/external/archspec/cpu/alias.py

@@ -0,0 +1,88 @@
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""Aliases for microarchitecture features."""
+# pylint: disable=useless-object-inheritance
+from .schema import TARGETS_JSON, LazyDictionary
+
+_FEATURE_ALIAS_PREDICATE = {}
+
+
+class FeatureAliasTest(object):
+    """A test that must be passed for a feature alias to succeed.
+
+    Args:
+        rules (dict): dictionary of rules to be met. Each key must be a
+            valid alias predicate
+    """
+
+    # pylint: disable=too-few-public-methods
+    def __init__(self, rules):
+        self.rules = rules
+        self.predicates = []
+        for name, args in rules.items():
+            self.predicates.append(_FEATURE_ALIAS_PREDICATE[name](args))
+
+    def __call__(self, microarchitecture):
+        return all(feature_test(microarchitecture) for feature_test in self.predicates)
+
+
+def _feature_aliases():
+    """Returns the dictionary of all defined feature aliases."""
+    json_data = TARGETS_JSON["feature_aliases"]
+    aliases = {}
+    for alias, rules in json_data.items():
+        aliases[alias] = FeatureAliasTest(rules)
+    return aliases
+
+
+FEATURE_ALIASES = LazyDictionary(_feature_aliases)
+
+
+def alias_predicate(func):
+    """Decorator to register a predicate that can be used to evaluate
+    feature aliases.
+    """
+    name = func.__name__
+
+    # Check we didn't register anything else with the same name
+    if name in _FEATURE_ALIAS_PREDICATE:
+        msg = 'the alias predicate "{0}" already exists'.format(name)
+        raise KeyError(msg)
+
+    _FEATURE_ALIAS_PREDICATE[name] = func
+
+    return func
+
+
+@alias_predicate
+def reason(_):
+    """This predicate returns always True and it's there to allow writing
+    a documentation string in the JSON file to explain why an alias is needed.
+    """
+    return lambda x: True
+
+
+@alias_predicate
+def any_of(list_of_features):
+    """Returns a predicate that is True if any of the feature in the
+    list is in the microarchitecture being tested, False otherwise.
+    """
+
+    def _impl(microarchitecture):
+        return any(x in microarchitecture for x in list_of_features)
+
+    return _impl
+
+
+@alias_predicate
+def families(list_of_families):
+    """Returns a predicate that is True if the architecture family of
+    the microarchitecture being tested is in the list, False otherwise.
+    """
+
+    def _impl(microarchitecture):
+        return str(microarchitecture.family) in list_of_families
+
+    return _impl

lib/spack/external/archspec/cpu/detect.py

@@ -1,7 +1,8 @@
-# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
-# Spack Project Developers. See the top-level COPYRIGHT file for details.
+# Copyright 2019-2020 Lawrence Livermore National Security, LLC and other
+# Archspec Project Developers. See the top-level COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
+"""Detection of CPU microarchitectures"""
 import collections
 import functools
 import os
@@ -12,16 +13,16 @@
 
 import six
 
-from .microarchitecture import generic_microarchitecture, targets
-from .schema import targets_json
+from .microarchitecture import generic_microarchitecture, TARGETS
+from .schema import TARGETS_JSON
 
 #: Mapping from operating systems to chain of commands
 #: to obtain a dictionary of raw info on the current cpu
-info_factory = collections.defaultdict(list)
+INFO_FACTORY = collections.defaultdict(list)
 
 #: Mapping from micro-architecture families (x86_64, ppc64le, etc.) to
 #: functions checking the compatibility of the host with a given target
-compatibility_checks = {}
+COMPATIBILITY_CHECKS = {}
 
 
 def info_dict(operating_system):
@@ -32,8 +33,9 @@ def info_dict(operating_system):
         operating_system (str or tuple): operating system for which the marked
             function is a viable factory of raw info dictionaries.
     """
+
     def decorator(factory):
-        info_factory[operating_system].append(factory)
+        INFO_FACTORY[operating_system].append(factory)
 
         @functools.wraps(factory)
         def _impl():
@@ -41,10 +43,10 @@ def _impl():
 
             # Check that info contains a few mandatory fields
             msg = 'field "{0}" is missing from raw info dictionary'
-            assert 'vendor_id' in info, msg.format('vendor_id')
-            assert 'flags' in info, msg.format('flags')
-            assert 'model' in info, msg.format('model')
-            assert 'model_name' in info, msg.format('model_name')
+            assert "vendor_id" in info, msg.format("vendor_id")
+            assert "flags" in info, msg.format("flags")
+            assert "model" in info, msg.format("model")
+            assert "model_name" in info, msg.format("model_name")
 
             return info
 
@@ -53,15 +55,15 @@ def _impl():
     return decorator
 
 
-@info_dict(operating_system='Linux')
+@info_dict(operating_system="Linux")
 def proc_cpuinfo():
     """Returns a raw info dictionary by parsing the first entry of
     ``/proc/cpuinfo``
     """
     info = {}
-    with open('/proc/cpuinfo') as file:
+    with open("/proc/cpuinfo") as file:
         for line in file:
-            key, separator, value = line.partition(':')
+            key, separator, value = line.partition(":")
 
             # If there's no separator and info was already populated
             # according to what's written here:
@@ -70,44 +72,43 @@ def proc_cpuinfo():
             #
             # we are on a blank line separating two cpus. Exit early as
             # we want to read just the first entry in /proc/cpuinfo
-            if separator != ':' and info:
+            if separator != ":" and info:
                 break
 
             info[key.strip()] = value.strip()
     return info
 
 
-def check_output(args, env):
-    output = subprocess.Popen(
-        args, stdout=subprocess.PIPE, env=env
-    ).communicate()[0]
-    return six.text_type(output.decode('utf-8'))
+def _check_output(args, env):
+    output = subprocess.Popen(args, stdout=subprocess.PIPE, env=env).communicate()[0]
+    return six.text_type(output.decode("utf-8"))
 
 
-@info_dict(operating_system='Darwin')
+@info_dict(operating_system="Darwin")
 def sysctl_info_dict():
     """Returns a raw info dictionary parsing the output of sysctl."""
     # Make sure that /sbin and /usr/sbin are in PATH as sysctl is
     # usually found there
     child_environment = dict(os.environ.items())
-    search_paths = child_environment.get('PATH', '').split(os.pathsep)
-    for additional_path in ('/sbin', '/usr/sbin'):
+    search_paths = child_environment.get("PATH", "").split(os.pathsep)
+    for additional_path in ("/sbin", "/usr/sbin"):
         if additional_path not in search_paths:
             search_paths.append(additional_path)
-    child_environment['PATH'] = os.pathsep.join(search_paths)
+    child_environment["PATH"] = os.pathsep.join(search_paths)
 
     def sysctl(*args):
-        return check_output(
-            ['sysctl'] + list(args), env=child_environment
-        ).strip()
+        return _check_output(["sysctl"] + list(args), env=child_environment).strip()
 
-    flags = (sysctl('-n', 'machdep.cpu.features').lower() + ' '
-             + sysctl('-n', 'machdep.cpu.leaf7_features').lower())
+    flags = (
+        sysctl("-n", "machdep.cpu.features").lower()
+        + " "
+        + sysctl("-n", "machdep.cpu.leaf7_features").lower()
+    )
     info = {
-        'vendor_id': sysctl('-n', 'machdep.cpu.vendor'),
-        'flags': flags,
-        'model': sysctl('-n', 'machdep.cpu.model'),
-        'model name': sysctl('-n', 'machdep.cpu.brand_string')
+        "vendor_id": sysctl("-n", "machdep.cpu.vendor"),
+        "flags": flags,
+        "model": sysctl("-n", "machdep.cpu.model"),
+        "model name": sysctl("-n", "machdep.cpu.brand_string"),
     }
     return info
 
@@ -117,16 +118,16 @@ def adjust_raw_flags(info):
     slightly different representations.
     """
     # Flags detected on Darwin turned to their linux counterpart
-    flags = info.get('flags', [])
-    d2l = targets_json['conversions']['darwin_flags']
+    flags = info.get("flags", [])
+    d2l = TARGETS_JSON["conversions"]["darwin_flags"]
     for darwin_flag, linux_flag in d2l.items():
         if darwin_flag in flags:
-            info['flags'] += ' ' + linux_flag
+            info["flags"] += " " + linux_flag
 
 
 def adjust_raw_vendor(info):
     """Adjust the vendor field to make it human readable"""
-    if 'CPU implementer' not in info:
+    if "CPU implementer" not in info:
         return
 
     # Mapping numeric codes to vendor (ARM). This list is a merge from
@@ -136,10 +137,10 @@ def adjust_raw_vendor(info):
     # https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile
     # https://github.com/gcc-mirror/gcc/blob/master/gcc/config/aarch64/aarch64-cores.def
     # https://patchwork.kernel.org/patch/10524949/
-    arm_vendors = targets_json['conversions']['arm_vendors']
-    arm_code = info['CPU implementer']
+    arm_vendors = TARGETS_JSON["conversions"]["arm_vendors"]
+    arm_code = info["CPU implementer"]
     if arm_code in arm_vendors:
-        info['CPU implementer'] = arm_vendors[arm_code]
+        info["CPU implementer"] = arm_vendors[arm_code]
 
 
 def raw_info_dictionary():
@@ -148,12 +149,13 @@ def raw_info_dictionary():
     This function calls all the viable factories one after the other until
     there's one that is able to produce the requested information.
     """
+    # pylint: disable=broad-except
     info = {}
-    for factory in info_factory[platform.system()]:
+    for factory in INFO_FACTORY[platform.system()]:
         try:
             info = factory()
-        except Exception as e:
-            warnings.warn(str(e))
+        except Exception as exc:
+            warnings.warn(str(exc))
 
         if info:
             adjust_raw_flags(info)
@@ -173,9 +175,10 @@ def compatible_microarchitectures(info):
     architecture_family = platform.machine()
     # If a tester is not registered, be conservative and assume no known
     # target is compatible with the host
-    tester = compatibility_checks.get(architecture_family, lambda x, y: False)
-    return [x for x in targets.values() if tester(info, x)] or \
-           [generic_microarchitecture(architecture_family)]
+    tester = COMPATIBILITY_CHECKS.get(architecture_family, lambda x, y: False)
+    return [x for x in TARGETS.values() if tester(info, x)] or [
+        generic_microarchitecture(architecture_family)
+    ]
 
 
 def host():
@@ -188,7 +191,9 @@ def host():
 
     # Reverse sort of the depth for the inheritance tree among only targets we
     # can use. This gets the newest target we satisfy.
-    return sorted(candidates, key=lambda t: len(t.ancestors), reverse=True)[0]
+    return sorted(
+        candidates, key=lambda t: (len(t.ancestors), len(t.features)), reverse=True
+    )[0]
 
 
 def compatibility_check(architecture_family):
@@ -207,50 +212,59 @@ def compatibility_check(architecture_family):
         architecture_family = (architecture_family,)
 
     def decorator(func):
+        # pylint: disable=fixme
         # TODO: on removal of Python 2.6 support this can be re-written as
         # TODO: an update +  a dict comprehension
         for arch_family in architecture_family:
-            compatibility_checks[arch_family] = func
+            COMPATIBILITY_CHECKS[arch_family] = func
 
         return func
 
     return decorator
 
 
-@compatibility_check(architecture_family=('ppc64le', 'ppc64'))
+@compatibility_check(architecture_family=("ppc64le", "ppc64"))
 def compatibility_check_for_power(info, target):
+    """Compatibility check for PPC64 and PPC64LE architectures."""
     basename = platform.machine()
-    generation_match = re.search(r'POWER(\d+)', info.get('cpu', ''))
+    generation_match = re.search(r"POWER(\d+)", info.get("cpu", ""))
     generation = int(generation_match.group(1))
 
     # We can use a target if it descends from our machine type and our
     # generation (9 for POWER9, etc) is at least its generation.
-    arch_root = targets[basename]
-    return (target == arch_root or arch_root in target.ancestors) \
-        and target.generation <= generation
+    arch_root = TARGETS[basename]
+    return (
+        target == arch_root or arch_root in target.ancestors
+    ) and target.generation <= generation
 
 
-@compatibility_check(architecture_family='x86_64')
+@compatibility_check(architecture_family="x86_64")
 def compatibility_check_for_x86_64(info, target):
-    basename = 'x86_64'
-    vendor = info.get('vendor_id', 'generic')
-    features = set(info.get('flags', '').split())
+    """Compatibility check for x86_64 architectures."""
+    basename = "x86_64"
+    vendor = info.get("vendor_id", "generic")
+    features = set(info.get("flags", "").split())
 
     # We can use a target if it descends from our machine type, is from our
     # vendor, and we have all of its features
-    arch_root = targets[basename]
-    return (target == arch_root or arch_root in target.ancestors) \
-        and (target.vendor == vendor or target.vendor == 'generic') \
+    arch_root = TARGETS[basename]
+    return (
+        (target == arch_root or arch_root in target.ancestors)
+        and (target.vendor == vendor or target.vendor == "generic")
         and target.features.issubset(features)
+    )
 
 
-@compatibility_check(architecture_family='aarch64')
+@compatibility_check(architecture_family="aarch64")
 def compatibility_check_for_aarch64(info, target):
-    basename = 'aarch64'
-    features = set(info.get('Features', '').split())
-    vendor = info.get('CPU implementer', 'generic')
+    """Compatibility check for AARCH64 architectures."""
+    basename = "aarch64"
+    features = set(info.get("Features", "").split())
+    vendor = info.get("CPU implementer", "generic")
 
-    arch_root = targets[basename]
-    return (target == arch_root or arch_root in target.ancestors) \
-        and (target.vendor == vendor or target.vendor == 'generic') \
+    arch_root = TARGETS[basename]
+    return (
+        (target == arch_root or arch_root in target.ancestors)
+        and (target.vendor == vendor or target.vendor == "generic")
         and target.features.issubset(features)
+    )