prototype: check commits against the tip of known branches

Recipes that are not actually required for LBANN or DiHydrogen to
build. These should be concretized within the same environment or
installed via PIP using the same Python that installed LBANN.
Removing these will help eliminate build time failures that are
actually associated with Python tools, not LBANN.

.github/ISSUE_TEMPLATE/build_error.yml

@@ -16,19 +16,29 @@ body:
     attributes:
       label: Steps to reproduce the issue
       description: |
-        Fill in the exact spec you are trying to build and the relevant part of the error message
-      placeholder: |
+        Fill in the console output from the exact spec you are trying to build.
+      value: |
         ```console
-        $ spack install <spec>
+        $ spack spec -I <spec>
         ...
         ```
+  - type: textarea
+    id: error
+    attributes:
+      label: Error message
+      description: |
+        Please post the error message from spack inside the `<details>` tag below:
+      value: |
+        <details><summary>Error message</summary><pre>
+        ...
+        </pre></details>
     validations:
       required: true
   - type: textarea
     id: information
     attributes:
       label: Information on your system
-      description: Please include the output of `spack debug report`
+      description: Please include the output of `spack debug report`.
     validations:
       required: true
   - type: markdown

.github/workflows/bootstrap.yml

@@ -31,7 +31,7 @@ jobs:
               bzip2 curl file gcc-c++ gcc gcc-gfortran git gnupg2 gzip \
               make patch unzip which xz python3 python3-devel tree \
               cmake bison bison-devel libstdc++-static
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       - name: Setup repo and non-root user
         run: |
           git --version
@@ -61,7 +61,7 @@ jobs:
               bzip2 curl file g++ gcc gfortran git gnupg2 gzip \
               make patch unzip xz-utils python3 python3-dev tree \
               cmake bison
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       - name: Setup repo and non-root user
         run: |
           git --version
@@ -90,7 +90,7 @@ jobs:
           apt-get install -y \
               bzip2 curl file g++ gcc gfortran git gnupg2 gzip \
               make patch unzip xz-utils python3 python3-dev tree
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       - name: Setup repo and non-root user
         run: |
           git --version
@@ -118,7 +118,7 @@ jobs:
               bzip2 curl file gcc-c++ gcc gcc-fortran tar git gpg2 gzip \
               make patch unzip which xz python3 python3-devel tree \
               cmake bison
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       - name: Setup repo and non-root user
         run: |
           git --version
@@ -138,7 +138,7 @@ jobs:
       - name: Install dependencies
         run: |
           brew install cmake bison@2.7 tree
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       - name: Bootstrap clingo
         run: |
           source share/spack/setup-env.sh
@@ -157,8 +157,8 @@ jobs:
       - name: Install dependencies
         run: |
           brew install tree
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-      - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+      - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
         with:
           python-version: ${{ matrix.python-version }}
       - name: Bootstrap clingo
@@ -174,8 +174,8 @@ jobs:
       matrix:
         python-version: ['2.7', '3.5', '3.6', '3.7', '3.8', '3.9']
     steps:
-      - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-      - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+      - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
         with:
           python-version: ${{ matrix.python-version }}
       - name: Setup repo and non-root user
@@ -202,7 +202,7 @@ jobs:
           apt-get install -y \
               bzip2 curl file g++ gcc patchelf gfortran git gzip \
               make patch unzip xz-utils python3 python3-dev tree
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - name: Setup repo and non-root user
         run: |
           git --version
@@ -231,7 +231,7 @@ jobs:
               bzip2 curl file g++ gcc patchelf gfortran git gzip \
               make patch unzip xz-utils python3 python3-dev tree \
               gawk
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - name: Setup repo and non-root user
         run: |
           git --version
@@ -256,7 +256,7 @@ jobs:
           brew install tree
           # Remove GnuPG since we want to bootstrap it
           sudo rm -rf /usr/local/bin/gpg
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - name: Bootstrap GnuPG
         run: |
           source share/spack/setup-env.sh
@@ -272,7 +272,7 @@ jobs:
           brew install gawk tree
           # Remove GnuPG since we want to bootstrap it
           sudo rm -rf /usr/local/bin/gpg
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846
       - name: Bootstrap GnuPG
         run: |
           source share/spack/setup-env.sh

.github/workflows/build-containers.yml

@@ -37,7 +37,7 @@ jobs:
     name: Build ${{ matrix.dockerfile[0] }}
     steps:
       - name: Checkout
-        uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+        uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
 
       - name: Set Container Tag Normal (Nightly)
         run: |
@@ -67,7 +67,7 @@ jobs:
         uses: docker/setup-buildx-action@94ab11c41e45d028884a99163086648e898eed25 # @v1
 
       - name: Log in to GitHub Container Registry
-        uses: docker/login-action@42d299face0c5c43a0487c477f595ac9cf22f1a7 # @v1
+        uses: docker/login-action@dd4fa0671be5250ee6f50aedf4cb05514abda2c7 # @v1
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
@@ -75,13 +75,13 @@ jobs:
 
       - name: Log in to DockerHub
         if: ${{ github.event_name != 'pull_request' }}
-        uses: docker/login-action@42d299face0c5c43a0487c477f595ac9cf22f1a7 # @v1
+        uses: docker/login-action@dd4fa0671be5250ee6f50aedf4cb05514abda2c7 # @v1
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Build & Deploy ${{ matrix.dockerfile[1] }}
-        uses: docker/build-push-action@a66e35b9cbcf4ad0ea91ffcaf7bbad63ad9e0229 # @v2
+        uses: docker/build-push-action@7f9d37fa544684fb73bfe4835ed7214c255ce02b # @v2
         with:
           file: share/spack/docker/${{matrix.dockerfile[1]}}
           platforms: ${{ matrix.dockerfile[2] }}

.github/workflows/install_spack.sh

@@ -2,19 +2,7 @@
 . 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 find
 spack compiler info apple-clang
 spack debug report
+spack solve zlib

.github/workflows/macos_python.yml

@@ -24,23 +24,23 @@ jobs:
     name: gcc with clang
     runs-on: macos-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: spack install
       run: |
         . .github/workflows/install_spack.sh
         # 9.2.0 is the latest version on which we apply homebrew patch
-        spack install -v --fail-fast gcc@9.2.0 %apple-clang
+        spack install -v --fail-fast gcc@11.2.0 %apple-clang
 
   install_jupyter_clang:
     name: jupyter
     runs-on: macos-latest
     timeout-minutes: 700
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: spack install
@@ -52,8 +52,8 @@ jobs:
     name: scipy, mpl, pd
     runs-on: macos-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: spack install

.github/workflows/unit_tests.yaml

@@ -15,8 +15,8 @@ jobs:
   validate:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: Install Python Packages
@@ -31,10 +31,10 @@ jobs:
   style:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: Install Python packages
@@ -57,7 +57,7 @@ jobs:
       packages: ${{ steps.filter.outputs.packages }}
       with_coverage: ${{ steps.coverage.outputs.with_coverage }}
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       if: ${{ github.event_name == 'push' }}
       with:
         fetch-depth: 0
@@ -106,10 +106,10 @@ jobs:
         - python-version: 3.9
           concretizer: original
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install System packages
@@ -121,12 +121,16 @@ jobs:
               patchelf cmake bison libbison-dev kcov
     - name: Install Python packages
       run: |
-          pip install --upgrade pip six setuptools pytest codecov coverage[toml]
+          pip install --upgrade pip six setuptools pytest codecov "coverage[toml]<=6.2"
           # ensure style checks are not skipped in unit tests for python >= 3.6
           # note that true/false (i.e., 1/0) are opposite in conditions in python and bash
           if python -c 'import sys; sys.exit(not sys.version_info >= (3, 6))'; then
               pip install --upgrade flake8 isort>=4.3.5 mypy>=0.900 black
           fi
+    - name: Pin pathlib for Python 2.7
+      if: ${{ matrix.python-version == 2.7 }}
+      run: |
+          pip install -U pathlib2==2.3.6
     - name: Setup git configuration
       run: |
           # Need this for the git tests to succeed.
@@ -167,10 +171,10 @@ jobs:
     needs: [ validate, style, changes ]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: Install System packages
@@ -180,7 +184,7 @@ jobs:
           sudo apt-get install -y coreutils kcov csh zsh tcsh fish dash bash
     - name: Install Python packages
       run: |
-          pip install --upgrade pip six setuptools pytest codecov coverage[toml]
+          pip install --upgrade pip six setuptools pytest codecov coverage[toml]==6.2
     - name: Setup git configuration
       run: |
           # Need this for the git tests to succeed.
@@ -214,7 +218,7 @@ jobs:
           dnf install -y \
               bzip2 curl file gcc-c++ gcc gcc-gfortran git gnupg2 gzip \
               make patch tcl unzip which xz
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
     - name: Setup repo and non-root user
       run: |
           git --version
@@ -233,10 +237,10 @@ jobs:
     needs: [ validate, style, changes ]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: Install System packages
@@ -248,7 +252,7 @@ jobs:
               patchelf kcov
     - name: Install Python packages
       run: |
-          pip install --upgrade pip six setuptools pytest codecov coverage[toml] clingo
+          pip install --upgrade pip six setuptools pytest codecov coverage[toml]==6.2 clingo
     - name: Setup git configuration
       run: |
           # Need this for the git tests to succeed.
@@ -282,16 +286,16 @@ jobs:
       matrix:
         python-version: [3.8]
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install Python packages
       run: |
           pip install --upgrade pip six setuptools
-          pip install --upgrade pytest codecov coverage[toml]
+          pip install --upgrade pytest codecov coverage[toml]==6.2
     - name: Setup Homebrew packages
       run: |
         brew install dash fish gcc gnupg2 kcov
@@ -327,13 +331,13 @@ jobs:
     needs: [ validate, style, changes ]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@ec3a7ce113134d7a93b817d10a8272cb61118579 # @v2
-    - uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6 # @v2
+    - uses: actions/checkout@a12a3943b4bdde767164f792f33f40b04645d846 # @v2
+    - uses: actions/setup-python@0ebf233433c08fb9061af664d501c3f3ff0e9e20 # @v2
       with:
         python-version: 3.9
     - name: Install Python packages
       run: |
-        pip install --upgrade pip six setuptools pytest codecov coverage[toml]
+        pip install --upgrade pip six setuptools pytest codecov coverage[toml]==6.2
     - name: Package audits (with coverage)
       if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       run: |

COPYRIGHT

@@ -34,10 +34,18 @@ 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: altgraph
+PackageHomePage: https://altgraph.readthedocs.io/en/latest/index.html
+PackageLicenseDeclared: MIT
+
 PackageName: argparse
 PackageHomePage: https://pypi.python.org/pypi/argparse
 PackageLicenseDeclared: Python-2.0
 
+PackageName: astunparse
+PackageHomePage: https://github.com/simonpercivall/astunparse
+PackageLicenseDeclared: Python-2.0
+
 PackageName: attrs
 PackageHomePage: https://github.com/python-attrs/attrs
 PackageLicenseDeclared: MIT
@@ -62,6 +70,10 @@ PackageName: jsonschema
 PackageHomePage: https://pypi.python.org/pypi/jsonschema
 PackageLicenseDeclared: MIT
 
+PackageName: macholib
+PackageHomePage: https://macholib.readthedocs.io/en/latest/index.html
+PackageLicenseDeclared: MIT
+
 PackageName: markupsafe
 PackageHomePage: https://pypi.python.org/pypi/MarkupSafe
 PackageLicenseDeclared: BSD-3-Clause
@@ -93,11 +105,3 @@ PackageLicenseDeclared: Apache-2.0 OR MIT
 PackageName: six
 PackageHomePage: https://pypi.python.org/pypi/six
 PackageLicenseDeclared: MIT
-
-PackageName: macholib
-PackageHomePage: https://macholib.readthedocs.io/en/latest/index.html
-PackageLicenseDeclared: MIT
-
-PackageName: altgraph
-PackageHomePage: https://altgraph.readthedocs.io/en/latest/index.html
-PackageLicenseDeclared: MIT

LICENSE-MIT

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2013-2020 LLNS, LLC and other Spack Project Developers.
+Copyright (c) 2013-2022 LLNS, LLC and other Spack Project Developers.
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

SECURITY.md

@@ -10,6 +10,7 @@ For more on Spack's release structure, see
 | Version | Supported          |
 | ------- | ------------------ |
 | develop | :white_check_mark: |
+| 0.17.x  | :white_check_mark: |
 | 0.16.x  | :white_check_mark: |
 
 ## Reporting a Vulnerability

bin/spack

@@ -1,7 +1,7 @@
 #!/bin/sh
 # -*- python -*-
 #
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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)

bin/spack-python

@@ -1,6 +1,6 @@
 #!/bin/sh
 #
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/concretizer.yaml

@@ -0,0 +1,17 @@
+# -------------------------------------------------------------------------
+# This is the default spack configuration file.
+#
+# Settings here are versioned with Spack and are intended to provide
+# sensible defaults out of the box. Spack maintainers should edit this
+# file to keep it current.
+#
+# Users can override these settings by editing
+# `$SPACK_ROOT/etc/spack/concretizer.yaml`, `~/.spack/concretizer.yaml`,
+# or by adding a `concretizer:` section to an environment.
+# -------------------------------------------------------------------------
+concretizer:
+  # Whether to consider installed packages or packages from buildcaches when
+  # concretizing specs. If `true`, we'll try to use as many installs/binaries
+  # as possible, rather than building. If `false`, we'll always give you a fresh
+  # concretization.
+  reuse: false

etc/spack/defaults/config.yaml

@@ -155,14 +155,17 @@ config:
 
   # 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. Spack will
   #       try to bootstrap the logic solver, if not already available.
   #
+  #   'original': Spack's original greedy, fixed-point concretizer. This
+  #       algorithm can make decisions too early and will not backtrack
+  #       sufficiently for many specs. This will soon be deprecated in
+  #       favor of clingo.
+  #
+  # See `concretizer.yaml` for more settings you can fine-tune when
+  # using clingo.
   concretizer: clingo
 
 

etc/spack/defaults/modules.yaml

@@ -46,7 +46,13 @@ modules:
     enable:
       - tcl
 
+    tcl:
+      all:
+        autoload: none
+
     # Default configurations if lmod is enabled
     lmod:
+      all:
+        autoload: direct
       hierarchy:
         - mpi

etc/spack/defaults/packages.yaml

@@ -34,6 +34,7 @@ packages:
       java: [openjdk, jdk, ibm-java]
       jpeg: [libjpeg-turbo, libjpeg]
       lapack: [openblas, amdlibflame]
+      libllvm: [llvm, llvm-amdgpu]
       lua-lang: [lua, lua-luajit]
       mariadb-client: [mariadb-c-client, mariadb]
       mkl: [intel-mkl]

lib/spack/docs/analyze.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/basic_usage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -194,9 +194,9 @@ Reusing installed dependencies
 
 .. warning::
 
-   The ``--reuse`` option described here is experimental, and it will
-   likely be replaced with a different option and configuration settings
-   in the next Spack release.
+   The ``--reuse`` option described here will become the default installation
+   method in the next Spack version, and you will be able to get the current
+   behavior by using ``spack install --fresh``.
 
 By default, when you run ``spack install``, Spack tries to build a new
 version of the package you asked for, along with updated versions of
@@ -216,6 +216,9 @@ the ``mpich`` will be build with the installed versions, if possible.
 You can use the :ref:`spack spec -I <cmd-spack-spec>` command to see what
 will be reused and what will be built before you install.
 
+You can configure Spack to use the ``--reuse`` behavior by default in
+``concretizer.yaml``.
+
 .. _cmd-spack-uninstall:
 
 ^^^^^^^^^^^^^^^^^^^
@@ -1280,7 +1283,7 @@ Normally users don't have to bother specifying the architecture if they
 are installing software for their current host, as in that case the
 values will be detected automatically.  If you need fine-grained control
 over which packages use which targets (or over *all* packages' default
-target), see :ref:`concretization-preferences`.
+target), see :ref:`package-preferences`.
 
 .. admonition:: Cray machines
 

lib/spack/docs/binary_caches.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -209,11 +209,49 @@ Specific limitations include:
   then Spack will not add a new external entry (``spack config blame packages``
   can help locate all external entries).
 
-.. _concretization-preferences:
+.. _concretizer-options:
 
---------------------------
-Concretization Preferences
---------------------------
+----------------------
+Concretizer options
+----------------------
+
+``packages.yaml`` gives the concretizer preferences for specific packages,
+but you can also use ``concretizer.yaml`` to customize aspects of the
+algorithm it uses to select the dependencies you install:
+
+.. _code-block: yaml
+
+   concretizer:
+     # Whether to consider installed packages or packages from buildcaches when
+     # concretizing specs. If `true`, we'll try to use as many installs/binaries
+     # as possible, rather than building. If `false`, we'll always give you a fresh
+     # concretization.
+     reuse: false
+
+^^^^^^^^^^^^^^^^
+``reuse``
+^^^^^^^^^^^^^^^^
+
+This controls whether Spack will prefer to use installed packages (``true``), or
+whether it will do a "fresh" installation and prefer the latest settings from
+``package.py`` files and ``packages.yaml`` (``false``). .
+
+You can use ``spack install --reuse`` to enable reuse for a single installation,
+and you can use ``spack install --fresh`` to do a fresh install if ``reuse`` is
+enabled by default.
+
+.. note::
+
+   ``reuse: false`` is the current default, but ``reuse: true`` will be the default
+   in the next Spack release. You will still be able to use ``spack install --fresh``
+   to get the old behavior.
+
+
+.. _package-preferences:
+
+-------------------
+Package Preferences
+-------------------
 
 Spack can be configured to prefer certain compilers, package
 versions, dependencies, and variants during concretization.
@@ -269,6 +307,7 @@ concretization rules.  A provider lists a value that packages may
 ``depend_on`` (e.g, MPI) and a list of rules for fulfilling that
 dependency.
 
+
 .. _package_permissions:
 
 -------------------

lib/spack/docs/build_systems.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/autotoolspackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/custompackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/inteloneapipackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -649,7 +649,7 @@ follow `the next section <intel-install-libs_>`_ instead.
 
    * If you specified a custom variant (for example ``+vtune``) you may want to add this as your
      preferred variant in the packages configuration for the ``intel-parallel-studio`` package
-     as described in :ref:`concretization-preferences`. Otherwise you will have to specify
+     as described in :ref:`package-preferences`. Otherwise you will have to specify
      the variant everytime ``intel-parallel-studio`` is being used as ``mkl``, ``fftw`` or ``mpi``
      implementation to avoid pulling in a different variant.
 
@@ -811,13 +811,13 @@ by one of the following means:
      $ spack install libxc@3.0.0%intel
 
 
-* Alternatively, request Intel compilers implicitly by concretization preferences.
+* Alternatively, request Intel compilers implicitly by package preferences.
   Configure the order of compilers in the appropriate ``packages.yaml`` file,
   under either an ``all:`` or client-package-specific entry, in a
   ``compiler:`` list. Consult the Spack documentation for
   `Configuring Package Preferences <https://spack-tutorial.readthedocs.io/en/latest/tutorial_configuration.html#configuring-package-preferences>`_
   and
-  :ref:`Concretization Preferences <concretization-preferences>`.
+  :ref:`Package Preferences <package-preferences>`.
 
 Example: ``etc/spack/packages.yaml`` might simply contain:
 
@@ -867,7 +867,7 @@ virtual package, in order of decreasing preference.  To learn more about the
 ``providers:`` settings, see the Spack tutorial for
 `Configuring Package Preferences <https://spack-tutorial.readthedocs.io/en/latest/tutorial_configuration.html#configuring-package-preferences>`_
 and the section
-:ref:`Concretization Preferences <concretization-preferences>`.
+:ref:`Package Preferences <package-preferences>`.
 
 Example: The following fairly minimal example for ``packages.yaml`` shows how
 to exclusively use the standalone ``intel-mkl`` package for all the linear

lib/spack/docs/build_systems/makefilepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/mesonpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/multiplepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/pythonpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -9,216 +9,80 @@
 PythonPackage
 -------------
 
-Python packages and modules have their own special build system.
+Python packages and modules have their own special build system. This
+documentation covers everything you'll need to know in order to write
+a Spack build recipe for a Python library.
 
-^^^^^^
-Phases
-^^^^^^
+^^^^^^^^^^^
+Terminology
+^^^^^^^^^^^
 
-The ``PythonPackage`` base class provides the following phases that
-can be overridden:
+In the Python ecosystem, there are a number of terms that are
+important to understand.
 
-* ``build``
-* ``build_py``
-* ``build_ext``
-* ``build_clib``
-* ``build_scripts``
-* ``install``
-* ``install_lib``
-* ``install_headers``
-* ``install_scripts``
-* ``install_data``
+**PyPI**
+   The `Python Package Index <https://pypi.org/>`_, where most Python
+   libraries are hosted.
 
-These are all standard ``setup.py`` commands and can be found by running:
+**sdist**
+   Source distributions, distributed as tarballs (.tar.gz) and zip
+   files (.zip). Contain the source code of the package.
 
-.. code-block:: console
+**bdist**
+   Built distributions, distributed as wheels (.whl). Contain the
+   pre-built library.
 
-   $ python setup.py --help-commands
+**wheel**
+   A binary distribution format common in the Python ecosystem. This
+   file is actually just a zip file containing specific metadata and
+   code. See the
+   `documentation <https://packaging.python.org/en/latest/specifications/binary-distribution-format/>`_
+   for more details.
 
+**build frontend**
+   Command-line tools used to build and install wheels. Examples
+   include `pip <https://pip.pypa.io/>`_,
+   `build <https://pypa-build.readthedocs.io/>`_, and
+   `installer <https://installer.readthedocs.io/>`_.
 
-By default, only the ``build`` and ``install`` phases are run:
+**build backend**
+   Libraries used to define how to build a wheel. Examples
+   include `setuptools <https://setuptools.pypa.io/>`__,
+   `flit <https://flit.readthedocs.io/>`_, and
+   `poetry <https://python-poetry.org/>`_.
 
-#. ``build`` - build everything needed to install
-#. ``install`` - install everything from build directory
+^^^^^^^^^^^
+Downloading
+^^^^^^^^^^^
 
-If for whatever reason you need to run more phases, simply modify your
-``phases`` list like so:
-
-.. code-block:: python
-
-   phases = ['build_ext', 'install']
-
-
-Each phase provides a function ``<phase>`` that runs:
-
-.. code-block:: console
-
-   $ python -s setup.py --no-user-cfg <phase>
-
-
-Each phase also has a ``<phase_args>`` function that can pass arguments to
-this call. All of these functions are empty except for the ``install_args``
-function, which passes ``--prefix=/path/to/installation/prefix``. There is
-also some additional logic specific to setuptools and eggs.
-
-If you need to run a phase that is not a standard ``setup.py`` command,
-you'll need to define a function for it like so:
-
-.. code-block:: python
-
-   phases = ['configure', 'build', 'install']
-
-   def configure(self, spec, prefix):
-       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
-^^^^^^^^^^^^^^^
-
-Python packages can be identified by the presence of a ``setup.py`` file.
-This file is used by package managers like ``pip`` to determine a
-package's dependencies and the version of dependencies required, so if
-the ``setup.py`` file is not accurate, the package will not build properly.
-For this reason, the ``setup.py`` file should be fairly reliable. If the
-documentation and ``setup.py`` disagree on something, the ``setup.py``
-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``.
-
-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:
-
-^^^^
-PyPI
-^^^^
-
-The vast majority of Python packages are hosted on PyPI (The Python
-Package Index), which is :ref:`preferred over GitHub <pypi-vs-github>`
-for downloading packages. ``pip`` only supports packages hosted on PyPI, making
-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::
+The first step in packaging a Python library is to figure out where
+to download it from. The vast majority of Python packages are hosted
+on `PyPI <https://pypi.org/>`_, which is
+:ref:`preferred over GitHub <pypi-vs-github>` for downloading
+packages. Search for the package name on PyPI to find the project
+page. The project page is usually located 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
-^^^^^^^^^^^
-
-The top of the PyPI downloads page contains a description of the
-package. The first line is usually a short description, while there
-may be a several line "Project Description" that follows. Choose whichever
-is more useful. You can also get these descriptions on the command-line
-using:
-
-.. code-block:: console
-
-   $ python setup.py --description
-   $ python setup.py --long-description
-
-
-^^^^^^^^
-Homepage
-^^^^^^^^
-
-Package developers use ``setup.py`` to upload new versions to PyPI.
-The ``setup`` method often passes metadata like ``homepage`` to PyPI.
-This metadata is displayed on the left side of the download page.
-Search for the text "Homepage" under "Project links" to find it. You
-should use this page instead of the PyPI page if they differ. You can
-also get the homepage on the command-line by running:
-
-.. code-block:: console
-
-   $ python setup.py --url
-
-
-^^^
-URL
-^^^
-
-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``.
-
-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::
+On the project page, there is a "Download files" tab containing
+download URLs. Whenever possible, we prefer to build Spack packages
+from source. If PyPI only has wheels, check to see if the project is
+hosted on GitHub and see if GitHub has source distributions. The
+project page usually has a "Homepage" and/or "Source code" link for
+this. If the project is closed-source, it may only have wheels
+available. For example, ``py-azureml-sdk`` is closed-source and can
+be downloaded from::
 
    https://pypi.io/packages/py3/a/azureml_sdk/azureml_sdk-1.11.0-py3-none-any.whl
 
+Once you've found a URL to download the package from, run:
 
-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:
+.. code-block:: console
 
-.. code-block:: python
+   $ spack create <url>
 
-   version('1.11.0', sha256='d8c9d24ea90457214d798b0d922489863dad518adde3638e08ef62de28fb183a', expand=False)
+
+to create a new package template.
 
 .. _pypi-vs-github:
 
@@ -226,11 +90,13 @@ try to extract the wheel:
 PyPI vs. GitHub
 """""""""""""""
 
-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:
+Many packages are hosted on PyPI, but are developed on GitHub or
+another version control system hosting service. The source code can
+be downloaded from either location, but PyPI is preferred for the
+following reasons:
 
-#. PyPI contains the bare minimum number of files needed 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.
@@ -267,252 +133,124 @@ 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.
 
-Use the :ref:`pypi attribute <pypi>` to facilitate construction of PyPI package
-references.
+The only reason to use GitHub instead of PyPI is if PyPI only has
+wheels or if the PyPI sdist is missing a file needed to build the
+package. If this is the case, please add a comment above the ``url``
+explaining this.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^
-Build system dependencies
-^^^^^^^^^^^^^^^^^^^^^^^^^
+^^^^
+PyPI
+^^^^
 
-There are a few dependencies common to the ``PythonPackage`` build system.
-
-""""""
-Python
-""""""
-
-Obviously, every ``PythonPackage`` needs Python at build-time to run
-``python setup.py build && python setup.py install``. Python is also
-needed at run-time if you want to import the module. Due to backwards
-incompatible changes between Python 2 and 3, it is very important to
-specify which versions of Python are supported. If the documentation
-mentions that Python 3 is required, this can be specified as:
+Since PyPI is so commonly used to host Python libraries, 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
 
-   depends_on('python@3:', type=('build', 'run'))
+   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/'
 
 
-If Python 2 is required, this would look like:
+is equivalent to:
 
 .. code-block:: python
 
-   depends_on('python@:2', type=('build', 'run'))
+   pypi = 'setuptools/setuptools-49.2.0.zip'
 
 
-If Python 2.7 is the only version that works, you can use:
+If a package has a different homepage listed on PyPI, you can
+override it by setting your own ``homepage``.
+
+^^^^^^^^^^^
+Description
+^^^^^^^^^^^
+
+The top of the PyPI project page contains a short description of the
+package. The "Project description" tab may also contain a longer
+description of the package. Either of these can be used to populate
+the package docstring.
+
+^^^^^^^^^^^^^
+Build backend
+^^^^^^^^^^^^^
+
+Once you've determined the basic metadata for a package, the next
+step is to determine the build backend. ``PythonPackage`` uses
+`pip <https://pip.pypa.io/>`_ to install the package, but pip
+requires a backend to actually build the package.
+
+To determine the build backend, look for a ``pyproject.toml`` file.
+If there is no ``pyproject.toml`` file and only a ``setup.py`` or
+``setup.cfg`` file, you can assume that the project uses
+:ref:`setuptools`. If there is a ``pyproject.toml`` file, see if it
+contains a ``[build-system]`` section. For example:
+
+.. code-block:: toml
+
+   [build-system]
+   requires = [
+       "setuptools>=42",
+       "wheel",
+   ]
+   build-backend = "setuptools.build_meta"
+
+
+This section does two things: the ``requires`` key lists build
+dependencies of the project, and the ``build-backend`` key defines
+the build backend. All of these build dependencies should be added as
+dependencies to your package:
 
 .. code-block:: python
 
-   depends_on('python@2.7:2.8', type=('build', 'run'))
+   depends_on('py-setuptools@42:', type='build')
 
 
-The documentation may not always specify supported Python versions.
-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:
+Note that ``py-wheel`` is already listed as a build dependency in the
+``PythonPackage`` base class, so you don't need to add it unless you
+need to specify a specific version requirement or change the
+dependency type.
 
-.. code-block:: python
+See `PEP 517 <https://www.python.org/dev/peps/pep-0517/>`_ and
+`PEP 518 <https://www.python.org/dev/peps/pep-0518/>`_ for more
+information on the design of ``pyproject.toml``.
 
-   python_requires='>=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*'
+Depending on which build backend a project uses, there are various
+places that run-time dependencies can be listed.
 
+"""""""""
+distutils
+"""""""""
 
-You may also find a version check at the top of the ``setup.py``:
+Before the introduction of setuptools and other build backends,
+Python packages had to rely on the built-in distutils library.
+Distutils is missing many of the features that setuptools and other
+build backends offer, and users are encouraged to use setuptools
+instead. In fact, distutils was deprecated in Python 3.10 and will be
+removed in Python 3.12. Because of this, pip actually replaces all
+imports of distutils with setuptools. If a package uses distutils,
+you should instead add a build dependency on setuptools. Check for a
+``requirements.txt`` file that may list dependencies of the project.
 
-.. code-block:: python
-
-   if sys.version_info[:2] < (2, 7) or (3, 0) <= sys.version_info[:2] < (3, 4):
-       raise RuntimeError("Python version 2.7 or >= 3.4 required.")
-
-
-This can be converted to Spack's spec notation like so:
-
-.. code-block:: python
-
-   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', 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:
 
 """"""""""
 setuptools
 """"""""""
 
-Originally, the Python language had a single build system called
-distutils, which is built into Python. Distutils provided a common
-framework for package authors to describe their project and how it
-should be built. However, distutils was not without limitations.
-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 90% of
-the Python packages in Spack.
-
-Since setuptools isn't built-in to Python, you need to add it as a
-dependency. To determine whether or not a package uses setuptools,
-search the file for an import statement like:
-
-.. code-block:: python
-
-   import setuptools
-
-
-or:
-
-.. code-block:: python
-
-   from setuptools import setup
-
-
-Some packages are designed to work with both setuptools and distutils,
-so you may find something like:
-
-.. code-block:: python
-
-   try:
-       from setuptools import setup
-   except ImportError:
-       from distutils.core import setup
-
-
-This uses setuptools if available, and falls back to distutils if not.
-In this case, you would still want to add a setuptools dependency, as
-it offers us more control over the installation.
-
-Unless specified otherwise, setuptools is usually a build-only dependency.
-That is, it is needed to install the software, but is not needed at
-run-time. This can be specified as:
-
-.. code-block:: python
-
-   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
-""""""
-
-Compared to compiled languages, interpreted languages like Python can
-be quite a bit slower. To work around this, some Python developers
-rewrite computationally demanding sections of code in C, a process
-referred to as "cythonizing". In order to build these package, you
-need to add a build dependency on cython:
-
-.. code-block:: python
-
-   depends_on('py-cython', type='build')
-
-
-Look for references to "cython" in the ``setup.py`` to determine
-whether or not this is necessary. Cython may be optional, but
-even then you should list it as a required dependency. Spack is
-designed to compile software, and is meant for HPC facilities
-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
-^^^^^^^^^^^^^^^^^^^
-
-When you install a package with ``pip``, it reads the ``setup.py``
-file in order to determine the dependencies of the package.
-If the dependencies are not yet installed, ``pip`` 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, ``pip`` 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 Python extensions, which involves
-   symlinking the package installation prefix to the Python 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 ``pip`` and won't have to
-worry about it. Always check the ``setup.py`` to find the true
-dependencies.
-
-If the package relies on ``distutils``, it may not explicitly list its
-dependencies. Check for statements like:
-
-.. code-block:: python
-
-   try:
-       import numpy
-   except ImportError:
-       raise ImportError("numpy must be installed prior to installation")
-
-
-Obviously, this means that ``py-numpy`` is a dependency.
-
-If the package uses ``setuptools``, check for the following clues:
+If the ``pyproject.toml`` lists ``setuptools.build_meta`` as a
+``build-backend``, or if the package has a ``setup.py`` that imports
+``setuptools``, or if the package has a ``setup.cfg`` file, then it
+uses setuptools to build. Setuptools is a replacement for the
+distutils library, and has almost the exact same API. Dependencies
+can be listed in the ``setup.py`` or ``setup.cfg`` file. Look for the
+following arguments:
 
 * ``python_requires``
 
-  As mentioned above, this specifies which versions of Python are
-  required.
+  This specifies the version of Python that is required.
 
 * ``setup_requires``
 
@@ -524,43 +262,88 @@ If the package uses ``setuptools``, check for the following clues:
   These packages are required for building and installation. You can
   add them with ``type=('build', 'run')``.
 
-* ``extra_requires``
+* ``extras_require``
 
   These packages are optional dependencies that enable additional
   functionality. You should add a variant that optionally adds these
   dependencies. This variant should be False by default.
 
-* ``test_requires``
+* ``tests_require``
 
   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. 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
-of all of the package's dependencies. Don't be fooled. This file is
-used by tools like Travis to install the pre-requisites for the
-package... and a whole bunch of other things. It often contains
-dependencies only needed for unit tests, like:
+See https://setuptools.pypa.io/en/latest/userguide/dependency_management.html
+for more information on how setuptools handles dependency management.
+See `PEP 440 <https://www.python.org/dev/peps/pep-0440/#version-specifiers>`_
+for documentation on version specifiers in setuptools.
 
-* mock
-* nose
-* pytest
+""""
+flit
+""""
 
-It can also contain dependencies for building the documentation, like
-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.
+There are actually two possible ``build-backend`` for flit, ``flit``
+and ``flit_core``. If you see these in the ``pyproject.toml``, add a
+build dependency to your package. With flit, all dependencies are
+listed directly in the ``pyproject.toml`` file. Older versions of
+flit used to store this info in a ``flit.ini`` file, so check for
+this too.
 
-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.
+Either of these files may contain keys like:
 
-If you are write a recipe for a package that only distributes wheels,
-check the ``METADATA`` file for lines like::
+* ``requires-python``
 
+  This specifies the version of Python that is required
+
+* ``dependencies`` or ``requires``
+
+  These packages are required for building and installation. You can
+  add them with ``type=('build', 'run')``.
+
+* ``project.optional-dependencies`` or ``requires-extra``
+
+  This section includes keys with lists of optional dependencies
+  needed to enable those features. You should add a variant that
+  optionally adds these dependencies. This variant should be False
+  by default.
+
+See https://flit.readthedocs.io/en/latest/pyproject_toml.html for
+more information.
+
+""""""
+poetry
+""""""
+
+Like flit, poetry also has two possible ``build-backend``, ``poetry``
+and ``poetry_core``. If you see these in the ``pyproject.toml``, add
+a build dependency to your package. With poetry, all dependencies are
+listed directly in the ``pyproject.toml`` file. Dependencies are
+listed in a ``[tool.poetry.dependencies]`` section, and use a
+`custom syntax <https://python-poetry.org/docs/dependency-specification/#version-constraints>`_
+for specifying the version requirements. Note that ``~=`` works
+differently in poetry than in setuptools and flit for versions that
+start with a zero.
+
+""""""
+wheels
+""""""
+
+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. Check for lines like::
+
+   Requires-Python: >=3.5,<4
    Requires-Dist: azureml-core (~=1.11.0)
    Requires-Dist: azureml-dataset-runtime[fuse] (~=1.11.0)
    Requires-Dist: azureml-train (~=1.11.0)
@@ -572,62 +355,58 @@ check the ``METADATA`` file for lines like::
    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``.
-
-""""""""""
-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 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
-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 found in
-``prefix/bin``.
+``Requires-Python`` is equivalent to ``python_requires`` and
+``Requires-Dist`` is equivalent to ``install_requires``.
+``Provides-Extra`` is used to name optional features (variants) and
+a ``Requires-Dist`` with ``extra == 'foo'`` will list any
+dependencies needed for that feature.
 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Passing arguments to setup.py
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-The default build and install phases should be sufficient to install
-most packages. However, you may want to pass additional flags to
-either phase.
+The default install phase should be sufficient to install most
+packages. However, the installation instructions for a package may
+suggest passing certain flags to the ``setup.py`` call. The
+``PythonPackage`` class has two techniques for doing this.
 
-You can view the available options for a particular phase with:
+""""""""""""""
+Global options
+""""""""""""""
 
-.. code-block:: console
-
-   $ python setup.py <phase> --help
-
-
-Each phase provides a ``<phase_args>`` function that can be used to
-pass arguments to that phase. For example,
-`py-numpy <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/py-numpy/package.py>`_
-adds:
+These flags are added directly after ``setup.py`` when pip runs
+``python setup.py install``. For example, the ``py-pyyaml`` package
+has an optional dependency on ``libyaml`` that can be enabled like so:
 
 .. code-block:: python
 
-   def build_args(self, spec, prefix):
-       args = []
+   def global_options(self, spec, prefix):
+       options = []
+       if '+libyaml' in spec:
+           options.append('--with-libyaml')
+       else:
+           options.append('--without-libyaml')
+       return options
 
-       # From NumPy 1.10.0 on it's possible to do a parallel build.
-       if self.version >= Version('1.10.0'):
-           # But Parallel build in Python 3.5+ is broken.  See:
-           # https://github.com/spack/spack/issues/7927
-           # https://github.com/scipy/scipy/issues/7112
-           if spec['python'].version < Version('3.5'):
-               args = ['-j', str(make_jobs)]
 
-       return args
+"""""""""""""""
+Install options
+"""""""""""""""
+
+These flags are added directly after ``install`` when pip runs
+``python setup.py install``. For example, the ``py-pyyaml`` package
+allows you to specify the directories to search for ``libyaml``:
+
+.. code-block:: python
+
+   def install_options(self, spec, prefix):
+       options = []
+       if '+libyaml' in spec:
+           options.extend([
+               spec['libyaml'].libs.search_flags,
+               spec['libyaml'].headers.include_flags,
+           ])
+       return options
 
 
 ^^^^^^^
@@ -669,9 +448,9 @@ a "package" is a directory containing files like:
 
 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
+The ``PythonPackage`` base class automatically detects these package
+and 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
@@ -692,10 +471,8 @@ This can be expressed like so:
    @property
    def import_modules(self):
        modules = ['yaml']
-
        if '+libyaml' in self.spec:
            modules.append('yaml.cyaml')
-
        return modules
 
 
@@ -713,8 +490,8 @@ Unit tests
 """"""""""
 
 The package may have its own unit or regression tests. Spack can
-run these tests during the installation by adding phase-appropriate
-test methods.
+run these tests during the installation by adding test methods after
+installation.
 
 For example, ``py-numpy`` adds the following as a check to run
 after the ``install`` phase:
@@ -740,34 +517,14 @@ when testing is enabled during the installation (i.e., ``spack install
 Setup file in a sub-directory
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-In order to be compatible with package managers like ``pip``, the package
-is required to place its ``setup.py`` in the root of the tarball. However,
-not every Python package cares about ``pip`` or PyPI. If you are installing
-a package that is not hosted on PyPI, you may find that it places its
-``setup.py`` in a sub-directory. To handle this, add the directory containing
-``setup.py`` to the package like so:
+Many C/C++ libraries provide optional Python bindings in a
+subdirectory. To tell pip which directory to build from, you can
+override the ``build_directory`` attribute. For example, if a package
+provides Python bindings in a ``python`` directory, you can use:
 
 .. code-block:: python
 
-   build_directory = 'source'
-
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Alternate names for setup.py
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-As previously mentioned, packages need to call their setup script ``setup.py``
-in order to be compatible with package managers like ``pip``. However, some
-packages like
-`py-meep <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/py-meep/package.py>`_  and
-`py-adios <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/py-adios/package.py>`_
-come with multiple setup scripts, one for a serial build and another for a
-parallel build. You can override the default name to use like so:
-
-.. code-block:: python
-
-   def setup_file(self):
-       return 'setup-mpi.py' if '+mpi' in self.spec else 'setup.py'
+   build_directory = 'python'
 
 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -781,10 +538,14 @@ on Python are not necessarily ``PythonPackage``'s.
 Choosing a build system
 """""""""""""""""""""""
 
-First of all, you need to select a build system. ``spack create`` usually
-does this for you, but if for whatever reason you need to do this manually,
-choose ``PythonPackage`` if and only if the package contains a ``setup.py``
-file.
+First of all, you need to select a build system. ``spack create``
+usually does this for you, but if for whatever reason you need to do
+this manually, choose ``PythonPackage`` if and only if the package
+contains one of the following files:
+
+* ``pyproject.toml``
+* ``setup.py``
+* ``setup.cfg``
 
 """""""""""""""""""""""
 Choosing a package name
@@ -857,10 +618,9 @@ having to add that module to ``PYTHONPATH``.
 
 When deciding between ``extends`` and ``depends_on``, the best rule of
 thumb is to check the installation prefix. If Python libraries are
-installed to ``prefix/lib/python2.7/site-packages`` (where 2.7 is the
-MAJOR.MINOR version of Python you used to install the package), then
-you should use ``extends``. If Python libraries are installed elsewhere
-or the only files that get installed reside in ``prefix/bin``, then
+installed to ``<prefix>/lib/pythonX.Y/site-packages``, then you
+should use ``extends``. If Python libraries are installed elsewhere
+or the only files that get installed reside in ``<prefix>/bin``, then
 don't use ``extends``, as symlinking the package wouldn't be useful.
 
 ^^^^^^^^^^^^^^^^^^^^^
@@ -893,4 +653,17 @@ External documentation
 ^^^^^^^^^^^^^^^^^^^^^^
 
 For more information on Python packaging, see:
-https://packaging.python.org/
+
+* https://packaging.python.org/
+
+For more information on build and installation frontend tools, see:
+
+* pip: https://pip.pypa.io/
+* build: https://pypa-build.readthedocs.io/
+* installer: https://installer.readthedocs.io/
+
+For more information on build backend tools, see:
+
+* setuptools: https://setuptools.pypa.io/
+* flit: https://flit.readthedocs.io/
+* poetry: https://python-poetry.org/

lib/spack/docs/build_systems/qmakepackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/rocmpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/rpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/rubypackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/sconspackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/wafpackage.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/config_yaml.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/configuration.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -13,12 +13,16 @@ Spack has many configuration files.  Here is a quick list of them, in
 case you want to skip directly to specific docs:
 
 * :ref:`compilers.yaml <compiler-config>`
+* :ref:`concretizer.yaml <concretizer-options>`
 * :ref:`config.yaml <config-yaml>`
 * :ref:`mirrors.yaml <mirrors>`
 * :ref:`modules.yaml <modules>`
 * :ref:`packages.yaml <build-settings>`
 * :ref:`repos.yaml <repositories>`
 
+You can also add any of these as inline configuration in ``spack.yaml``
+in an :ref:`environment <environment-configuration>`.
+
 -----------
 YAML Format
 -----------

lib/spack/docs/containers.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/contribution_guide.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/developer_guide.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/environments.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/extensions.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -38,8 +38,7 @@ obtained by cloning the corresponding git repository:
 
 .. code-block:: console
 
-   $ pwd
-   /home/user
+   $ cd ~/
    $ mkdir tmp && cd tmp
    $ git clone https://github.com/alalazo/spack-scripting.git
    Cloning into 'spack-scripting'...
@@ -62,7 +61,7 @@ paths to ``config.yaml``. In the case of our example this means ensuring that:
 
    config:
      extensions:
-     - /home/user/tmp/spack-scripting
+     - ~/tmp/spack-scripting
 
 is part of your configuration file. Once this is setup any command that the extension provides
 will be available from the command line:

lib/spack/docs/features.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/getting_started.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -271,9 +271,10 @@ Compiler configuration
 ----------------------
 
 Spack has the ability to build packages with multiple compilers and
-compiler versions. Spack searches for compilers on your machine
-automatically the first time it is run. It does this by inspecting
-your ``PATH``.
+compiler versions. Compilers can be made available to Spack by
+specifying them manually in ``compilers.yaml``, or automatically by
+running ``spack compiler find``, but for convenience Spack will
+automatically detect compilers the first time it needs them.
 
 .. _cmd-spack-compilers:
 
@@ -281,7 +282,7 @@ your ``PATH``.
 ``spack compilers``
 ^^^^^^^^^^^^^^^^^^^
 
-You can see which compilers spack has found by running ``spack
+You can see which compilers are available to Spack by running ``spack
 compilers`` or ``spack compiler list``:
 
 .. code-block:: console
@@ -320,9 +321,10 @@ An alias for ``spack compiler find``.
 ``spack compiler find``
 ^^^^^^^^^^^^^^^^^^^^^^^
 
-If you do not see a compiler in this list, but you want to use it with
-Spack, you can simply run ``spack compiler find`` with the path to
-where the compiler is installed.  For example:
+Lists the compilers currently available to Spack. If you do not see
+a compiler in this list, but you want to use it with Spack, you can
+simply run ``spack compiler find`` with the path to where the
+compiler is installed.  For example:
 
 .. code-block:: console
 

lib/spack/docs/index.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/known_issues.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/mirrors.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -615,44 +615,39 @@ modifications to either ``CPATH`` or ``LIBRARY_PATH``.
 Autoload dependencies
 """""""""""""""""""""
 
-In some cases it can be useful to have module files that automatically load
-their dependencies.  This may be the case for Python extensions, if not
-activated using ``spack activate``:
+Often it is required for a module to have its (transient) dependencies loaded as well.
+One example where this is useful is when one package needs to use executables provided
+by its dependency; when the dependency is autoloaded, the executable will be in the
+PATH. Similarly for scripting languages such as Python, packages and their dependencies
+have to be loaded together.
+
+Autoloading is enabled by default for LMod, as it has great builtin support for through
+the ``depends_on`` function. For Environment Modules it is disabled by default.
+
+Autoloading can also be enabled conditionally:
 
 .. code-block:: yaml
 
-   modules:
-     default:
-       tcl:
-         ^python:
-           autoload: 'direct'
+    modules:
+      default:
+        tcl:
+          all:
+            autoload: none
+          ^python:
+            autoload: direct
 
 The configuration file above will produce module files that will
 load their direct dependencies if the package installed depends on ``python``.
 The allowed values for the ``autoload`` statement are either ``none``,
-``direct`` or ``all``.  The default is ``none``.
-
-.. tip::
-  Building external software
-     Setting ``autoload`` to ``direct`` for all packages can be useful
-     when building software outside of a Spack installation that depends on
-     artifacts in that installation.  E.g. (adjust ``lmod`` vs ``tcl``
-     as appropriate):
-
-  .. code-block:: yaml
-
-     modules:
-       default:
-         lmod:
-           all:
-             autoload: 'direct'
+``direct`` or ``all``.
 
 .. note::
   TCL prerequisites
      In the ``tcl`` section of the configuration file it is possible to use
      the ``prerequisites`` directive that accepts the same values as
      ``autoload``. It will produce module files that have a ``prereq``
-     statement instead of automatically loading other modules.
+     statement, which can be used to autoload dependencies in some versions
+     of Environment Modules.
 
 ------------------------
 Maintaining Module Files

lib/spack/docs/monitoring.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/package_list.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/packaging_guide.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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)
@@ -705,7 +705,8 @@ as follows:
 
 #. The following special strings are considered larger than any other
    numeric or non-numeric version component, and satisfy the following
-   order between themselves: ``develop > main > master > head > trunk``.
+   order between themselves:
+   ``develop > main > master > head > trunk > stable``.
 
 #. Numbers are ordered numerically, are less than special strings, and
    larger than other non-numeric components.
@@ -1441,6 +1442,32 @@ The ``when`` clause follows the same syntax and accepts the same
 values as the ``when`` argument of
 :py:func:`spack.directives.depends_on`
 
+^^^^^^^^^^^^^^^
+Sticky Variants
+^^^^^^^^^^^^^^^
+
+The variant directive can be marked as ``sticky`` by setting to ``True`` the
+corresponding argument:
+
+.. code-block:: python
+
+   variant('bar', default=False, sticky=True)
+
+A ``sticky`` variant differs from a regular one in that it is always set
+to either:
+
+#. An explicit value appearing in a spec literal or
+#. Its default value
+
+The concretizer thus is not free to pick an alternate value to work
+around conflicts, but will error out instead.
+Setting this property on a variant is useful in cases where the
+variant allows some dangerous or controversial options (e.g. using unsupported versions
+of a compiler for a library) and the packager wants to ensure that
+allowing these options is done on purpose by the user, rather than
+automatically by the solver.
+
+
 ^^^^^^^^^^^^^^^^^^^
 Overriding Variants
 ^^^^^^^^^^^^^^^^^^^
@@ -2443,6 +2470,24 @@ Now, the ``py-numpy`` package can be used as an argument to ``spack
 activate``.  When it is activated, all the files in its prefix will be
 symbolically linked into the prefix of the python package.
 
+A package can only extend one other package at a time.  To support packages
+that may extend one of a list of other packages, Spack supports multiple
+``extends`` directives as long as at most one of them is selected as
+a dependency during concretization.  For example, a lua package could extend
+either lua or luajit, but not both:
+
+.. code-block:: python
+
+   class LuaLpeg(Package):
+       ...
+       variant('use_lua', default=True)
+       extends('lua', when='+use_lua')
+       extends('lua-luajit', when='~use_lua')
+       ...
+
+Now, a user can install, and activate, the ``lua-lpeg`` package for either
+lua or luajit.
+
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Adding additional constraints
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -2832,7 +2877,7 @@ be concretized on their system.  For example, one user may prefer packages
 built with OpenMPI and the Intel compiler.  Another user may prefer
 packages be built with MVAPICH and GCC.
 
-See the :ref:`concretization-preferences` section for more details.
+See the :ref:`package-preferences` section for more details.
 
 
 .. _group_when_spec:

lib/spack/docs/pipelines.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/repositories.rst

@@ -1,4 +1,4 @@
-.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/spack.yaml

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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 2013-2021 Lawrence Livermore National Security, LLC and other
+.. Copyright 2013-2022 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/env/cc

@@ -1,7 +1,7 @@
 #!/bin/sh
 # shellcheck disable=SC2034  # evals in this script fool shellcheck
 #
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/external/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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:
 
+altgraph
+--------
+
+* Homepage: https://altgraph.readthedocs.io/en/latest/index.html
+* Usage: dependency of macholib
+* Version: 0.17.2
+
 archspec
 --------
 
@@ -24,6 +31,22 @@
   vendored copy ever needs to be updated again:
   https://github.com/spack/spack/pull/6786/commits/dfcef577b77249106ea4e4c69a6cd9e64fa6c418
 
+astunparse
+----------------
+
+* Homepage: https://github.com/simonpercivall/astunparse
+* Usage: Unparsing Python ASTs for package hashes in Spack
+* Version: 1.6.3 (plus modifications)
+* Note: This is in ``spack.util.unparse`` because it's very heavily
+  modified, and we want to track coverage for it.
+  Specifically, we have modified this library to generate consistent unparsed ASTs
+  regardless of the Python version. It is based on:
+    1. The original ``astunparse`` library;
+    2. Modifications for consistency;
+    3. Backports from the ``ast.unparse`` function in Python 3.9 and later
+  The unparsing is now mostly consistent with upstream ``ast.unparse``, so if
+  we ever require Python 3.9 or higher, we can drop this external package.
+
 attrs
 ----------------
 
@@ -68,6 +91,13 @@
 * Version: 3.2.0 (last version before 2.7 and 3.6 support was dropped)
 * Note: We don't include tests or benchmarks; just what Spack needs.
 
+macholib
+--------
+
+* Homepage: https://macholib.readthedocs.io/en/latest/index.html#
+* Usage: Manipulation of Mach-o binaries for relocating macOS buildcaches on Linux
+* Version: 1.15.2
+
 markupsafe
 ----------
 
@@ -124,18 +154,4 @@
 * Usage: Python 2 and 3 compatibility utilities.
 * Version: 1.16.0
 
-macholib
---------
-
-* Homepage: https://macholib.readthedocs.io/en/latest/index.html#
-* Usage: Manipulation of Mach-o binaries for relocating macOS buildcaches on Linux
-* Version: 1.12
-
-altgraph
---------
-
-* Homepage: https://altgraph.readthedocs.io/en/latest/index.html
-* Usage: dependency of macholib
-* Version: 0.16.1
-
 """

lib/spack/external/altgraph/Dot.py

@@ -1,4 +1,4 @@
-'''
+"""
 altgraph.Dot - Interface to the dot language
 ============================================
 
@@ -107,7 +107,7 @@
     - for more details on how to control the graph drawing process see the
       `graphviz reference
         <http://www.research.att.com/sw/tools/graphviz/refs.html>`_.
-'''
+"""
 import os
 import warnings
 
@@ -115,25 +115,34 @@
 
 
 class Dot(object):
-    '''
+    """
     A  class providing a **graphviz** (dot language) representation
     allowing a fine grained control over how the graph is being
     displayed.
 
     If the :command:`dot` and :command:`dotty` programs are not in the current
     system path their location needs to be specified in the contructor.
-    '''
+    """
 
     def __init__(
-            self, graph=None, nodes=None, edgefn=None, nodevisitor=None,
-            edgevisitor=None, name="G", dot='dot', dotty='dotty',
-            neato='neato', graphtype="digraph"):
-        '''
+        self,
+        graph=None,
+        nodes=None,
+        edgefn=None,
+        nodevisitor=None,
+        edgevisitor=None,
+        name="G",
+        dot="dot",
+        dotty="dotty",
+        neato="neato",
+        graphtype="digraph",
+    ):
+        """
         Initialization.
-        '''
+        """
         self.name, self.attr = name, {}
 
-        assert graphtype in ['graph', 'digraph']
+        assert graphtype in ["graph", "digraph"]
         self.type = graphtype
 
         self.temp_dot = "tmp_dot.dot"
@@ -148,8 +157,10 @@ def __init__(
         if graph is not None and nodes is None:
             nodes = graph
         if graph is not None and edgefn is None:
+
             def edgefn(node, graph=graph):
                 return graph.out_nbrs(node)
+
         if nodes is None:
             nodes = ()
 
@@ -177,20 +188,19 @@ def edgefn(node, graph=graph):
                         self.edge_style(head, tail, **edgestyle)
 
     def style(self, **attr):
-        '''
+        """
         Changes the overall style
-        '''
+        """
         self.attr = attr
 
-    def display(self, mode='dot'):
-        '''
+    def display(self, mode="dot"):
+        """
         Displays the current graph via dotty
-        '''
+        """
 
-        if mode == 'neato':
+        if mode == "neato":
             self.save_dot(self.temp_neo)
-            neato_cmd = "%s -o %s %s" % (
-                self.neato, self.temp_dot, self.temp_neo)
+            neato_cmd = "%s -o %s %s" % (self.neato, self.temp_dot, self.temp_neo)
             os.system(neato_cmd)
         else:
             self.save_dot(self.temp_dot)
@@ -199,24 +209,24 @@ def display(self, mode='dot'):
         os.system(plot_cmd)
 
     def node_style(self, node, **kwargs):
-        '''
+        """
         Modifies a node style to the dot representation.
-        '''
+        """
         if node not in self.edges:
             self.edges[node] = {}
         self.nodes[node] = kwargs
 
     def all_node_style(self, **kwargs):
-        '''
+        """
         Modifies all node styles
-        '''
+        """
         for node in self.nodes:
             self.node_style(node, **kwargs)
 
     def edge_style(self, head, tail, **kwargs):
-        '''
+        """
         Modifies an edge style to the dot representation.
-        '''
+        """
         if tail not in self.nodes:
             raise GraphError("invalid node %s" % (tail,))
 
@@ -229,10 +239,10 @@ def edge_style(self, head, tail, **kwargs):
 
     def iterdot(self):
         # write graph title
-        if self.type == 'digraph':
-            yield 'digraph %s {\n' % (self.name,)
-        elif self.type == 'graph':
-            yield 'graph %s {\n' % (self.name,)
+        if self.type == "digraph":
+            yield "digraph %s {\n" % (self.name,)
+        elif self.type == "graph":
+            yield "graph %s {\n" % (self.name,)
 
         else:
             raise GraphError("unsupported graphtype %s" % (self.type,))
@@ -240,11 +250,11 @@ def iterdot(self):
         # write overall graph attributes
         for attr_name, attr_value in sorted(self.attr.items()):
             yield '%s="%s";' % (attr_name, attr_value)
-        yield '\n'
+        yield "\n"
 
         # some reusable patterns
-        cpatt = '%s="%s",'      # to separate attributes
-        epatt = '];\n'          # to end attributes
+        cpatt = '%s="%s",'  # to separate attributes
+        epatt = "];\n"  # to end attributes
 
         # write node attributes
         for node_name, node_attr in sorted(self.nodes.items()):
@@ -256,25 +266,24 @@ def iterdot(self):
         # write edge attributes
         for head in sorted(self.edges):
             for tail in sorted(self.edges[head]):
-                if self.type == 'digraph':
+                if self.type == "digraph":
                     yield '\t"%s" -> "%s" [' % (head, tail)
                 else:
                     yield '\t"%s" -- "%s" [' % (head, tail)
-                for attr_name, attr_value in \
-                        sorted(self.edges[head][tail].items()):
+                for attr_name, attr_value in sorted(self.edges[head][tail].items()):
                     yield cpatt % (attr_name, attr_value)
                 yield epatt
 
         # finish file
-        yield '}\n'
+        yield "}\n"
 
     def __iter__(self):
         return self.iterdot()
 
     def save_dot(self, file_name=None):
-        '''
+        """
         Saves the current graph representation into a file
-        '''
+        """
 
         if not file_name:
             warnings.warn(DeprecationWarning, "always pass a file_name")
@@ -284,19 +293,18 @@ def save_dot(self, file_name=None):
             for chunk in self.iterdot():
                 fp.write(chunk)
 
-    def save_img(self, file_name=None, file_type="gif", mode='dot'):
-        '''
+    def save_img(self, file_name=None, file_type="gif", mode="dot"):
+        """
         Saves the dot file as an image file
-        '''
+        """
 
         if not file_name:
             warnings.warn(DeprecationWarning, "always pass a file_name")
             file_name = "out"
 
-        if mode == 'neato':
+        if mode == "neato":
             self.save_dot(self.temp_neo)
-            neato_cmd = "%s -o %s %s" % (
-                self.neato, self.temp_dot, self.temp_neo)
+            neato_cmd = "%s -o %s %s" % (self.neato, self.temp_dot, self.temp_neo)
             os.system(neato_cmd)
             plot_cmd = self.dot
         else:
@@ -305,5 +313,9 @@ def save_img(self, file_name=None, file_type="gif", mode='dot'):
 
         file_name = "%s.%s" % (file_name, file_type)
         create_cmd = "%s -T%s %s -o %s" % (
-            plot_cmd, file_type, self.temp_dot, file_name)
+            plot_cmd,
+            file_type,
+            self.temp_dot,
+            file_name,
+        )
         os.system(create_cmd)

lib/spack/external/altgraph/Graph.py

@@ -13,9 +13,10 @@
   #--Nathan Denny, May 27, 1999
 """
 
-from altgraph import GraphError
 from collections import deque
 
+from altgraph import GraphError
+
 
 class Graph(object):
     """
@@ -58,8 +59,10 @@ def __init__(self, edges=None):
                     raise GraphError("Cannot create edge from %s" % (item,))
 
     def __repr__(self):
-        return '<Graph: %d nodes, %d edges>' % (
-            self.number_of_nodes(), self.number_of_edges())
+        return "<Graph: %d nodes, %d edges>" % (
+            self.number_of_nodes(),
+            self.number_of_edges(),
+        )
 
     def add_node(self, node, node_data=None):
         """
@@ -111,7 +114,7 @@ def add_edge(self, head_id, tail_id, edge_data=1, create_nodes=True):
             self.nodes[tail_id][0].append(edge)
             self.nodes[head_id][1].append(edge)
         except KeyError:
-            raise GraphError('Invalid nodes %s -> %s' % (head_id, tail_id))
+            raise GraphError("Invalid nodes %s -> %s" % (head_id, tail_id))
 
         # store edge information
         self.edges[edge] = (head_id, tail_id, edge_data)
@@ -124,13 +127,12 @@ def hide_edge(self, edge):
         time.
         """
         try:
-            head_id, tail_id, edge_data = \
-                self.hidden_edges[edge] = self.edges[edge]
+            head_id, tail_id, edge_data = self.hidden_edges[edge] = self.edges[edge]
             self.nodes[tail_id][0].remove(edge)
             self.nodes[head_id][1].remove(edge)
             del self.edges[edge]
         except KeyError:
-            raise GraphError('Invalid edge %s' % edge)
+            raise GraphError("Invalid edge %s" % edge)
 
     def hide_node(self, node):
         """
@@ -144,7 +146,7 @@ def hide_node(self, node):
                 self.hide_edge(edge)
             del self.nodes[node]
         except KeyError:
-            raise GraphError('Invalid node %s' % node)
+            raise GraphError("Invalid node %s" % node)
 
     def restore_node(self, node):
         """
@@ -157,7 +159,7 @@ def restore_node(self, node):
                 self.restore_edge(edge)
             del self.hidden_nodes[node]
         except KeyError:
-            raise GraphError('Invalid node %s' % node)
+            raise GraphError("Invalid node %s" % node)
 
     def restore_edge(self, edge):
         """
@@ -170,7 +172,7 @@ def restore_edge(self, edge):
             self.edges[edge] = head_id, tail_id, data
             del self.hidden_edges[edge]
         except KeyError:
-            raise GraphError('Invalid edge %s' % edge)
+            raise GraphError("Invalid edge %s" % edge)
 
     def restore_all_edges(self):
         """
@@ -203,7 +205,7 @@ def edge_by_id(self, edge):
             head, tail, data = self.edges[edge]
         except KeyError:
             head, tail = None, None
-            raise GraphError('Invalid edge %s' % edge)
+            raise GraphError("Invalid edge %s" % edge)
 
         return (head, tail)
 
@@ -339,7 +341,7 @@ def out_edges(self, node):
         try:
             return list(self.nodes[node][1])
         except KeyError:
-            raise GraphError('Invalid node %s' % node)
+            raise GraphError("Invalid node %s" % node)
 
     def inc_edges(self, node):
         """
@@ -348,7 +350,7 @@ def inc_edges(self, node):
         try:
             return list(self.nodes[node][0])
         except KeyError:
-            raise GraphError('Invalid node %s' % node)
+            raise GraphError("Invalid node %s" % node)
 
     def all_edges(self, node):
         """
@@ -488,7 +490,7 @@ def iterdfs(self, start, end=None, forward=True):
         The forward parameter specifies whether it is a forward or backward
         traversal.
         """
-        visited, stack = set([start]), deque([start])
+        visited, stack = {start}, deque([start])
 
         if forward:
             get_edges = self.out_edges
@@ -515,7 +517,7 @@ def iterdata(self, start, end=None, forward=True, condition=None):
         condition callback is only called when node_data is not None.
         """
 
-        visited, stack = set([start]), deque([start])
+        visited, stack = {start}, deque([start])
 
         if forward:
             get_edges = self.out_edges
@@ -547,7 +549,7 @@ def _iterbfs(self, start, end=None, forward=True):
         traversal.  Returns a list of tuples where the first value is the hop
         value the second value is the node id.
         """
-        queue, visited = deque([(start, 0)]), set([start])
+        queue, visited = deque([(start, 0)]), {start}
 
         # the direction of the bfs depends on the edges that are sampled
         if forward:

lib/spack/external/altgraph/GraphAlgo.py

@@ -1,7 +1,7 @@
-'''
+"""
 altgraph.GraphAlgo - Graph algorithms
 =====================================
-'''
+"""
 from altgraph import GraphError
 
 
@@ -28,9 +28,9 @@ def dijkstra(graph, start, end=None):
     Adapted to altgraph by Istvan Albert, Pennsylvania State University -
     June, 9 2004
     """
-    D = {}    # dictionary of final distances
-    P = {}    # dictionary of predecessors
-    Q = _priorityDictionary()    # estimated distances of non-final vertices
+    D = {}  # dictionary of final distances
+    P = {}  # dictionary of predecessors
+    Q = _priorityDictionary()  # estimated distances of non-final vertices
     Q[start] = 0
 
     for v in Q:
@@ -44,7 +44,8 @@ def dijkstra(graph, start, end=None):
             if w in D:
                 if vwLength < D[w]:
                     raise GraphError(
-                        "Dijkstra: found better path to already-final vertex")
+                        "Dijkstra: found better path to already-final vertex"
+                    )
             elif w not in Q or vwLength < Q[w]:
                 Q[w] = vwLength
                 P[w] = v
@@ -76,7 +77,7 @@ def shortest_path(graph, start, end):
 # Utility classes and functions
 #
 class _priorityDictionary(dict):
-    '''
+    """
     Priority dictionary using binary heaps (internal use only)
 
     David Eppstein, UC Irvine, 8 Mar 2002
@@ -92,22 +93,22 @@ class _priorityDictionary(dict):
            order. Each item is not removed until the next item is requested,
            so D[x] will still return a useful value until the next iteration
            of the for-loop.  Each operation takes logarithmic amortized time.
-    '''
+    """
 
     def __init__(self):
-        '''
+        """
         Initialize priorityDictionary by creating binary heap of pairs
         (value,key).  Note that changing or removing a dict entry will not
         remove the old pair from the heap until it is found by smallest()
         or until the heap is rebuilt.
-        '''
+        """
         self.__heap = []
         dict.__init__(self)
 
     def smallest(self):
-        '''
+        """
         Find smallest item after removing deleted items from front of heap.
-        '''
+        """
         if len(self) == 0:
             raise IndexError("smallest of empty priorityDictionary")
         heap = self.__heap
@@ -115,9 +116,11 @@ def smallest(self):
             lastItem = heap.pop()
             insertionPoint = 0
             while 1:
-                smallChild = 2*insertionPoint+1
-                if smallChild+1 < len(heap) and \
-                        heap[smallChild] > heap[smallChild+1]:
+                smallChild = 2 * insertionPoint + 1
+                if (
+                    smallChild + 1 < len(heap)
+                    and heap[smallChild] > heap[smallChild + 1]
+                ):
                     smallChild += 1
                 if smallChild >= len(heap) or lastItem <= heap[smallChild]:
                     heap[insertionPoint] = lastItem
@@ -127,22 +130,24 @@ def smallest(self):
         return heap[0][1]
 
     def __iter__(self):
-        '''
+        """
         Create destructive sorted iterator of priorityDictionary.
-        '''
+        """
+
         def iterfn():
             while len(self) > 0:
                 x = self.smallest()
                 yield x
                 del self[x]
+
         return iterfn()
 
     def __setitem__(self, key, val):
-        '''
+        """
         Change value stored in dictionary and add corresponding pair to heap.
         Rebuilds the heap if the number of deleted items gets large, to avoid
         memory leakage.
-        '''
+        """
         dict.__setitem__(self, key, val)
         heap = self.__heap
         if len(heap) > 2 * len(self):
@@ -152,15 +157,15 @@ def __setitem__(self, key, val):
             newPair = (val, key)
             insertionPoint = len(heap)
             heap.append(None)
-            while insertionPoint > 0 and newPair < heap[(insertionPoint-1)//2]:
-                heap[insertionPoint] = heap[(insertionPoint-1)//2]
-                insertionPoint = (insertionPoint-1)//2
+            while insertionPoint > 0 and newPair < heap[(insertionPoint - 1) // 2]:
+                heap[insertionPoint] = heap[(insertionPoint - 1) // 2]
+                insertionPoint = (insertionPoint - 1) // 2
             heap[insertionPoint] = newPair
 
     def setdefault(self, key, val):
-        '''
+        """
         Reimplement setdefault to pass through our customized __setitem__.
-        '''
+        """
         if key not in self:
             self[key] = val
         return self[key]

lib/spack/external/altgraph/GraphStat.py

@@ -1,11 +1,11 @@
-'''
+"""
 altgraph.GraphStat - Functions providing various graph statistics
 =================================================================
-'''
+"""
 
 
-def degree_dist(graph, limits=(0, 0), bin_num=10, mode='out'):
-    '''
+def degree_dist(graph, limits=(0, 0), bin_num=10, mode="out"):
+    """
     Computes the degree distribution for a graph.
 
     Returns a list of tuples where the first element of the tuple is the
@@ -15,10 +15,10 @@ def degree_dist(graph, limits=(0, 0), bin_num=10, mode='out'):
     Example::
 
         ....
-    '''
+    """
 
     deg = []
-    if mode == 'inc':
+    if mode == "inc":
         get_deg = graph.inc_degree
     else:
         get_deg = graph.out_degree
@@ -34,38 +34,38 @@ def degree_dist(graph, limits=(0, 0), bin_num=10, mode='out'):
     return results
 
 
-_EPS = 1.0/(2.0**32)
+_EPS = 1.0 / (2.0 ** 32)
 
 
 def _binning(values, limits=(0, 0), bin_num=10):
-    '''
+    """
     Bins data that falls between certain limits, if the limits are (0, 0) the
     minimum and maximum values are used.
 
     Returns a list of tuples where the first element of the tuple is the
     center of the bin and the second element of the tuple are the counts.
-    '''
+    """
     if limits == (0, 0):
         min_val, max_val = min(values) - _EPS, max(values) + _EPS
     else:
         min_val, max_val = limits
 
     # get bin size
-    bin_size = (max_val - min_val)/float(bin_num)
+    bin_size = (max_val - min_val) / float(bin_num)
     bins = [0] * (bin_num)
 
     # will ignore these outliers for now
     for value in values:
         try:
             if (value - min_val) >= 0:
-                index = int((value - min_val)/float(bin_size))
+                index = int((value - min_val) / float(bin_size))
                 bins[index] += 1
         except IndexError:
             pass
 
     # make it ready for an x,y plot
     result = []
-    center = (bin_size/2) + min_val
+    center = (bin_size / 2) + min_val
     for i, y in enumerate(bins):
         x = center + bin_size * i
         result.append((x, y))

lib/spack/external/altgraph/GraphUtil.py

@@ -1,31 +1,29 @@
-'''
+"""
 altgraph.GraphUtil - Utility classes and functions
 ==================================================
-'''
+"""
 
 import random
 from collections import deque
-from altgraph import Graph
-from altgraph import GraphError
+
+from altgraph import Graph, GraphError
 
 
-def generate_random_graph(
-        node_num, edge_num, self_loops=False, multi_edges=False):
-    '''
+def generate_random_graph(node_num, edge_num, self_loops=False, multi_edges=False):
+    """
     Generates and returns a :py:class:`~altgraph.Graph.Graph` instance with
     *node_num* nodes randomly connected by *edge_num* edges.
-    '''
+    """
     g = Graph.Graph()
 
     if not multi_edges:
         if self_loops:
             max_edges = node_num * node_num
         else:
-            max_edges = node_num * (node_num-1)
+            max_edges = node_num * (node_num - 1)
 
         if edge_num > max_edges:
-            raise GraphError(
-                "inconsistent arguments to 'generate_random_graph'")
+            raise GraphError("inconsistent arguments to 'generate_random_graph'")
 
     nodes = range(node_num)
 
@@ -52,17 +50,16 @@ def generate_random_graph(
     return g
 
 
-def generate_scale_free_graph(
-        steps, growth_num, self_loops=False, multi_edges=False):
-    '''
+def generate_scale_free_graph(steps, growth_num, self_loops=False, multi_edges=False):
+    """
     Generates and returns a :py:class:`~altgraph.Graph.Graph` instance that
-    will have *steps* \* *growth_num* nodes and a scale free (powerlaw)
+    will have *steps* \\* *growth_num* nodes and a scale free (powerlaw)
     connectivity. Starting with a fully connected graph with *growth_num*
     nodes at every step *growth_num* nodes are added to the graph and are
     connected to existing nodes with a probability proportional to the degree
     of these existing nodes.
-    '''
-    # FIXME: The code doesn't seem to do what the documentation claims.
+    """
+    # The code doesn't seem to do what the documentation claims.
     graph = Graph.Graph()
 
     # initialize the graph
@@ -113,7 +110,7 @@ def filter_stack(graph, head, filters):
       in *removes*.
     """
 
-    visited, removes, orphans = set([head]), set(), set()
+    visited, removes, orphans = {head}, set(), set()
     stack = deque([(head, head)])
     get_data = graph.node_data
     get_edges = graph.out_edges
@@ -137,8 +134,6 @@ def filter_stack(graph, head, filters):
                 visited.add(tail)
                 stack.append((last_good, tail))
 
-    orphans = [
-        (lg, tl)
-        for (lg, tl) in orphans if tl not in removes]
+    orphans = [(lg, tl) for (lg, tl) in orphans if tl not in removes]
 
     return visited, removes, orphans

lib/spack/external/altgraph/ObjectGraph.py

@@ -27,7 +27,7 @@ def __init__(self, graph=None, debug=0):
         graph.add_node(self, None)
 
     def __repr__(self):
-        return '<%s>' % (type(self).__name__,)
+        return "<%s>" % (type(self).__name__,)
 
     def flatten(self, condition=None, start=None):
         """
@@ -58,6 +58,7 @@ def iter_edges(lst, n):
                 if ident not in seen:
                     yield self.findNode(ident)
                     seen.add(ident)
+
         return iter_edges(outraw, 3), iter_edges(incraw, 2)
 
     def edgeData(self, fromNode, toNode):
@@ -87,12 +88,12 @@ def filterStack(self, filters):
         visited, removes, orphans = filter_stack(self.graph, self, filters)
 
         for last_good, tail in orphans:
-            self.graph.add_edge(last_good, tail, edge_data='orphan')
+            self.graph.add_edge(last_good, tail, edge_data="orphan")
 
         for node in removes:
             self.graph.hide_node(node)
 
-        return len(visited)-1, len(removes), len(orphans)
+        return len(visited) - 1, len(removes), len(orphans)
 
     def removeNode(self, node):
         """
@@ -135,7 +136,7 @@ def getRawIdent(self, node):
         """
         if node is self:
             return node
-        ident = getattr(node, 'graphident', None)
+        ident = getattr(node, "graphident", None)
         return ident
 
     def __contains__(self, node):
@@ -192,8 +193,7 @@ def msg(self, level, s, *args):
         Print a debug message with the given level
         """
         if s and level <= self.debug:
-            print("%s%s %s" % (
-                "  " * self.indent, s, ' '.join(map(repr, args))))
+            print("%s%s %s" % ("  " * self.indent, s, " ".join(map(repr, args))))
 
     def msgin(self, level, s, *args):
         """

lib/spack/external/altgraph/__init__.py

@@ -1,4 +1,4 @@
-'''
+"""
 altgraph - a python graph library
 =================================
 
@@ -138,13 +138,11 @@
   @newfield contributor: Contributors:
   @contributor: U{Reka Albert <http://www.phys.psu.edu/~ralbert/>}
 
-'''
-# import pkg_resources
-# __version__ = pkg_resources.require('altgraph')[0].version
-# pkg_resources is not finding the altgraph import despite the fact that it is in sys.path
-# there is no .dist-info or .egg-info for pkg_resources to query the version from
-# so it must be set manually
-__version__ = '0.16.1'
+"""
+import pkg_resources
+
+__version__ = pkg_resources.require("altgraph")[0].version
+
 
 class GraphError(ValueError):
     pass

lib/spack/external/macholib/MachO.py

@@ -3,21 +3,43 @@
 """
 from __future__ import print_function
 
-import sys
-import struct
 import os
-
-from .mach_o import MH_FILETYPE_SHORTNAMES, LC_DYSYMTAB, LC_SYMTAB
-from .mach_o import load_command, S_ZEROFILL, section_64, section
-from .mach_o import LC_REGISTRY, LC_ID_DYLIB, LC_SEGMENT, fat_header
-from .mach_o import LC_SEGMENT_64, MH_CIGAM_64, MH_MAGIC_64, FAT_MAGIC
-from .mach_o import mach_header, fat_arch64, FAT_MAGIC_64, fat_arch
-from .mach_o import LC_REEXPORT_DYLIB, LC_PREBOUND_DYLIB, LC_LOAD_WEAK_DYLIB
-from .mach_o import LC_LOAD_UPWARD_DYLIB, LC_LOAD_DYLIB, mach_header_64
-from .mach_o import MH_CIGAM, MH_MAGIC
-from .ptypes import sizeof
+import struct
+import sys
 
 from macholib.util import fileview
+
+from .mach_o import (
+    FAT_MAGIC,
+    FAT_MAGIC_64,
+    LC_DYSYMTAB,
+    LC_ID_DYLIB,
+    LC_LOAD_DYLIB,
+    LC_LOAD_UPWARD_DYLIB,
+    LC_LOAD_WEAK_DYLIB,
+    LC_PREBOUND_DYLIB,
+    LC_REEXPORT_DYLIB,
+    LC_REGISTRY,
+    LC_SEGMENT,
+    LC_SEGMENT_64,
+    LC_SYMTAB,
+    MH_CIGAM,
+    MH_CIGAM_64,
+    MH_FILETYPE_SHORTNAMES,
+    MH_MAGIC,
+    MH_MAGIC_64,
+    S_ZEROFILL,
+    fat_arch,
+    fat_arch64,
+    fat_header,
+    load_command,
+    mach_header,
+    mach_header_64,
+    section,
+    section_64,
+)
+from .ptypes import sizeof
+
 try:
     from macholib.compat import bytes
 except ImportError:
@@ -31,23 +53,23 @@
 if sys.version_info[0] == 2:
     range = xrange  # noqa: F821
 
-__all__ = ['MachO']
+__all__ = ["MachO"]
 
-_RELOCATABLE = set((
+_RELOCATABLE = {
     # relocatable commands that should be used for dependency walking
     LC_LOAD_DYLIB,
     LC_LOAD_UPWARD_DYLIB,
     LC_LOAD_WEAK_DYLIB,
     LC_PREBOUND_DYLIB,
     LC_REEXPORT_DYLIB,
-))
+}
 
 _RELOCATABLE_NAMES = {
-    LC_LOAD_DYLIB: 'load_dylib',
-    LC_LOAD_UPWARD_DYLIB: 'load_upward_dylib',
-    LC_LOAD_WEAK_DYLIB: 'load_weak_dylib',
-    LC_PREBOUND_DYLIB: 'prebound_dylib',
-    LC_REEXPORT_DYLIB: 'reexport_dylib',
+    LC_LOAD_DYLIB: "load_dylib",
+    LC_LOAD_UPWARD_DYLIB: "load_upward_dylib",
+    LC_LOAD_WEAK_DYLIB: "load_weak_dylib",
+    LC_PREBOUND_DYLIB: "prebound_dylib",
+    LC_REEXPORT_DYLIB: "reexport_dylib",
 }
 
 
@@ -65,13 +87,14 @@ def lc_str_value(offset, cmd_info):
     cmd_load, cmd_cmd, cmd_data = cmd_info
 
     offset -= sizeof(cmd_load) + sizeof(cmd_cmd)
-    return cmd_data[offset:].strip(b'\x00')
+    return cmd_data[offset:].strip(b"\x00")
 
 
 class MachO(object):
     """
     Provides reading/writing the Mach-O header of a specific existing file
     """
+
     #   filename   - the original filename of this mach-o
     #   sizediff   - the current deviation from the initial mach-o size
     #   header     - the mach-o header
@@ -91,7 +114,7 @@ def __init__(self, filename):
         # initialized by load
         self.fat = None
         self.headers = []
-        with open(filename, 'rb') as fp:
+        with open(filename, "rb") as fp:
             self.load(fp)
 
     def __repr__(self):
@@ -99,7 +122,7 @@ def __repr__(self):
 
     def load(self, fh):
         assert fh.tell() == 0
-        header = struct.unpack('>I', fh.read(4))[0]
+        header = struct.unpack(">I", fh.read(4))[0]
         fh.seek(0)
         if header in (FAT_MAGIC, FAT_MAGIC_64):
             self.load_fat(fh)
@@ -112,11 +135,9 @@ def load(self, fh):
     def load_fat(self, fh):
         self.fat = fat_header.from_fileobj(fh)
         if self.fat.magic == FAT_MAGIC:
-            archs = [fat_arch.from_fileobj(fh)
-                     for i in range(self.fat.nfat_arch)]
+            archs = [fat_arch.from_fileobj(fh) for i in range(self.fat.nfat_arch)]
         elif self.fat.magic == FAT_MAGIC_64:
-            archs = [fat_arch64.from_fileobj(fh)
-                     for i in range(self.fat.nfat_arch)]
+            archs = [fat_arch64.from_fileobj(fh) for i in range(self.fat.nfat_arch)]
         else:
             raise ValueError("Unknown fat header magic: %r" % (self.fat.magic))
 
@@ -132,19 +153,18 @@ def rewriteLoadCommands(self, *args, **kw):
 
     def load_header(self, fh, offset, size):
         fh.seek(offset)
-        header = struct.unpack('>I', fh.read(4))[0]
+        header = struct.unpack(">I", fh.read(4))[0]
         fh.seek(offset)
         if header == MH_MAGIC:
-            magic, hdr, endian = MH_MAGIC, mach_header, '>'
+            magic, hdr, endian = MH_MAGIC, mach_header, ">"
         elif header == MH_CIGAM:
-            magic, hdr, endian = MH_CIGAM, mach_header, '<'
+            magic, hdr, endian = MH_CIGAM, mach_header, "<"
         elif header == MH_MAGIC_64:
-            magic, hdr, endian = MH_MAGIC_64, mach_header_64, '>'
+            magic, hdr, endian = MH_MAGIC_64, mach_header_64, ">"
         elif header == MH_CIGAM_64:
-            magic, hdr, endian = MH_CIGAM_64, mach_header_64, '<'
+            magic, hdr, endian = MH_CIGAM_64, mach_header_64, "<"
         else:
-            raise ValueError("Unknown Mach-O header: 0x%08x in %r" % (
-                header, fh))
+            raise ValueError("Unknown Mach-O header: 0x%08x in %r" % (header, fh))
         hdr = MachOHeader(self, fh, offset, size, magic, hdr, endian)
         self.headers.append(hdr)
 
@@ -157,6 +177,7 @@ class MachOHeader(object):
     """
     Provides reading/writing the Mach-O header of a specific existing file
     """
+
     #   filename   - the original filename of this mach-o
     #   sizediff   - the current deviation from the initial mach-o size
     #   header     - the mach-o header
@@ -189,15 +210,19 @@ def __init__(self, parent, fh, offset, size, magic, hdr, endian):
 
     def __repr__(self):
         return "<%s filename=%r offset=%d size=%d endian=%r>" % (
-            type(self).__name__, self.parent.filename, self.offset, self.size,
-            self.endian)
+            type(self).__name__,
+            self.parent.filename,
+            self.offset,
+            self.size,
+            self.endian,
+        )
 
     def load(self, fh):
         fh = fileview(fh, self.offset, self.size)
         fh.seek(0)
 
         self.sizediff = 0
-        kw = {'_endian_': self.endian}
+        kw = {"_endian_": self.endian}
         header = self.mach_header.from_fileobj(fh, **kw)
         self.header = header
         # if header.magic != self.MH_MAGIC:
@@ -236,8 +261,9 @@ def load(self, fh):
                     section_cls = section_64
 
                 expected_size = (
-                    sizeof(klass) + sizeof(load_command) +
-                    (sizeof(section_cls) * cmd_cmd.nsects)
+                    sizeof(klass)
+                    + sizeof(load_command)
+                    + (sizeof(section_cls) * cmd_cmd.nsects)
                 )
                 if cmd_load.cmdsize != expected_size:
                     raise ValueError("Segment size mismatch")
@@ -248,12 +274,12 @@ def load(self, fh):
                         low_offset = min(low_offset, cmd_cmd.fileoff)
                 else:
                     # this one has multiple segments
-                    for j in range(cmd_cmd.nsects):
+                    for _j in range(cmd_cmd.nsects):
                         # read the segment
                         seg = section_cls.from_fileobj(fh, **kw)
                         # if the segment has a size and is not zero filled
                         # then its beginning is the offset of this segment
-                        not_zerofill = ((seg.flags & S_ZEROFILL) != S_ZEROFILL)
+                        not_zerofill = (seg.flags & S_ZEROFILL) != S_ZEROFILL
                         if seg.offset > 0 and seg.size > 0 and not_zerofill:
                             low_offset = min(low_offset, seg.offset)
                         if not_zerofill:
@@ -266,7 +292,7 @@ def load(self, fh):
                 # data is a list of segments
                 cmd_data = segs
 
-            # XXX: Disabled for now because writing back doesn't work
+            # These are disabled for now because writing back doesn't work
             # elif cmd_load.cmd == LC_CODE_SIGNATURE:
             #    c = fh.tell()
             #    fh.seek(cmd_cmd.dataoff)
@@ -280,17 +306,17 @@ def load(self, fh):
 
             else:
                 # data is a raw str
-                data_size = (
-                    cmd_load.cmdsize - sizeof(klass) - sizeof(load_command)
-                )
+                data_size = cmd_load.cmdsize - sizeof(klass) - sizeof(load_command)
                 cmd_data = fh.read(data_size)
             cmd.append((cmd_load, cmd_cmd, cmd_data))
             read_bytes += cmd_load.cmdsize
 
         # make sure the header made sense
         if read_bytes != header.sizeofcmds:
-            raise ValueError("Read %d bytes, header reports %d bytes" % (
-                read_bytes, header.sizeofcmds))
+            raise ValueError(
+                "Read %d bytes, header reports %d bytes"
+                % (read_bytes, header.sizeofcmds)
+            )
         self.total_size = sizeof(self.mach_header) + read_bytes
         self.low_offset = low_offset
 
@@ -303,8 +329,9 @@ def walkRelocatables(self, shouldRelocateCommand=_shouldRelocateCommand):
             if shouldRelocateCommand(lc.cmd):
                 name = _RELOCATABLE_NAMES[lc.cmd]
                 ofs = cmd.name - sizeof(lc.__class__) - sizeof(cmd.__class__)
-                yield idx, name, data[ofs:data.find(b'\x00', ofs)].decode(
-                        sys.getfilesystemencoding())
+                yield idx, name, data[
+                    ofs : data.find(b"\x00", ofs)  # noqa: E203
+                ].decode(sys.getfilesystemencoding())
 
     def rewriteInstallNameCommand(self, loadcmd):
         """Rewrite the load command of this dylib"""
@@ -317,8 +344,9 @@ def changedHeaderSizeBy(self, bytes):
         self.sizediff += bytes
         if (self.total_size + self.sizediff) > self.low_offset:
             print(
-                "WARNING: Mach-O header in %r may be too large to relocate" % (
-                    self.parent.filename,))
+                "WARNING: Mach-O header in %r may be too large to relocate"
+                % (self.parent.filename,)
+            )
 
     def rewriteLoadCommands(self, changefunc):
         """
@@ -327,22 +355,22 @@ def rewriteLoadCommands(self, changefunc):
         data = changefunc(self.parent.filename)
         changed = False
         if data is not None:
-            if self.rewriteInstallNameCommand(
-                    data.encode(sys.getfilesystemencoding())):
+            if self.rewriteInstallNameCommand(data.encode(sys.getfilesystemencoding())):
                 changed = True
-        for idx, name, filename in self.walkRelocatables():
+        for idx, _name, filename in self.walkRelocatables():
             data = changefunc(filename)
             if data is not None:
-                if self.rewriteDataForCommand(idx, data.encode(
-                        sys.getfilesystemencoding())):
+                if self.rewriteDataForCommand(
+                    idx, data.encode(sys.getfilesystemencoding())
+                ):
                     changed = True
         return changed
 
     def rewriteDataForCommand(self, idx, data):
         lc, cmd, old_data = self.commands[idx]
         hdrsize = sizeof(lc.__class__) + sizeof(cmd.__class__)
-        align = struct.calcsize('Q')
-        data = data + (b'\x00' * (align - (len(data) % align)))
+        align = struct.calcsize("Q")
+        data = data + (b"\x00" * (align - (len(data) % align)))
         newsize = hdrsize + len(data)
         self.commands[idx] = (lc, cmd, data)
         self.changedHeaderSizeBy(newsize - lc.cmdsize)
@@ -352,10 +380,17 @@ def rewriteDataForCommand(self, idx, data):
     def synchronize_size(self):
         if (self.total_size + self.sizediff) > self.low_offset:
             raise ValueError(
-                ("New Mach-O header is too large to relocate in %r "
-                 "(new size=%r, max size=%r, delta=%r)") % (
-                    self.parent.filename, self.total_size + self.sizediff,
-                    self.low_offset, self.sizediff))
+                (
+                    "New Mach-O header is too large to relocate in %r "
+                    "(new size=%r, max size=%r, delta=%r)"
+                )
+                % (
+                    self.parent.filename,
+                    self.total_size + self.sizediff,
+                    self.low_offset,
+                    self.sizediff,
+                )
+            )
         self.header.sizeofcmds += self.sizediff
         self.total_size = sizeof(self.mach_header) + self.header.sizeofcmds
         self.sizediff = 0
@@ -396,16 +431,16 @@ def write(self, fileobj):
 
         # zero out the unused space, doubt this is strictly necessary
         # and is generally probably already the case
-        fileobj.write(b'\x00' * (self.low_offset - fileobj.tell()))
+        fileobj.write(b"\x00" * (self.low_offset - fileobj.tell()))
 
     def getSymbolTableCommand(self):
-        for lc, cmd, data in self.commands:
+        for lc, cmd, _data in self.commands:
             if lc.cmd == LC_SYMTAB:
                 return cmd
         return None
 
     def getDynamicSymbolTableCommand(self):
-        for lc, cmd, data in self.commands:
+        for lc, cmd, _data in self.commands:
             if lc.cmd == LC_DYSYMTAB:
                 return cmd
         return None
@@ -414,22 +449,23 @@ def get_filetype_shortname(self, filetype):
         if filetype in MH_FILETYPE_SHORTNAMES:
             return MH_FILETYPE_SHORTNAMES[filetype]
         else:
-            return 'unknown'
+            return "unknown"
 
 
 def main(fn):
     m = MachO(fn)
     seen = set()
     for header in m.headers:
-        for idx, name, other in header.walkRelocatables():
+        for _idx, name, other in header.walkRelocatables():
             if other not in seen:
                 seen.add(other)
-                print('\t' + name + ": " + other)
+                print("\t" + name + ": " + other)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     import sys
-    files = sys.argv[1:] or ['/bin/ls']
+
+    files = sys.argv[1:] or ["/bin/ls"]
     for fn in files:
         print(fn)
         main(fn)

lib/spack/external/macholib/MachOGraph.py

@@ -8,10 +8,10 @@
 from altgraph.ObjectGraph import ObjectGraph
 
 from macholib.dyld import dyld_find
-from macholib.MachO import MachO
 from macholib.itergraphreport import itergraphreport
+from macholib.MachO import MachO
 
-__all__ = ['MachOGraph']
+__all__ = ["MachOGraph"]
 
 try:
     unicode
@@ -25,13 +25,14 @@ def __init__(self, filename):
         self.headers = ()
 
     def __repr__(self):
-        return '<%s graphident=%r>' % (type(self).__name__, self.graphident)
+        return "<%s graphident=%r>" % (type(self).__name__, self.graphident)
 
 
 class MachOGraph(ObjectGraph):
     """
     Graph data structure of Mach-O dependencies
     """
+
     def __init__(self, debug=0, graph=None, env=None, executable_path=None):
         super(MachOGraph, self).__init__(debug=debug, graph=graph)
         self.env = env
@@ -41,16 +42,18 @@ def __init__(self, debug=0, graph=None, env=None, executable_path=None):
     def locate(self, filename, loader=None):
         if not isinstance(filename, (str, unicode)):
             raise TypeError("%r is not a string" % (filename,))
-        if filename.startswith('@loader_path/') and loader is not None:
+        if filename.startswith("@loader_path/") and loader is not None:
             fn = self.trans_table.get((loader.filename, filename))
             if fn is None:
                 loader_path = loader.loader_path
 
                 try:
                     fn = dyld_find(
-                        filename, env=self.env,
+                        filename,
+                        env=self.env,
                         executable_path=self.executable_path,
-                        loader_path=loader_path)
+                        loader_path=loader_path,
+                    )
                     self.trans_table[(loader.filename, filename)] = fn
                 except ValueError:
                     return None
@@ -60,8 +63,8 @@ def locate(self, filename, loader=None):
             if fn is None:
                 try:
                     fn = dyld_find(
-                            filename, env=self.env,
-                            executable_path=self.executable_path)
+                        filename, env=self.env, executable_path=self.executable_path
+                    )
                     self.trans_table[filename] = fn
                 except ValueError:
                     return None
@@ -83,11 +86,11 @@ def run_file(self, pathname, caller=None):
         m = self.findNode(pathname, loader=caller)
         if m is None:
             if not os.path.exists(pathname):
-                raise ValueError('%r does not exist' % (pathname,))
+                raise ValueError("%r does not exist" % (pathname,))
             m = self.createNode(MachO, pathname)
-            self.createReference(caller, m, edge_data='run_file')
+            self.createReference(caller, m, edge_data="run_file")
             self.scan_node(m)
-        self.msgout(2, '')
+        self.msgout(2, "")
         return m
 
     def load_file(self, name, caller=None):
@@ -103,20 +106,20 @@ def load_file(self, name, caller=None):
                 self.scan_node(m)
             else:
                 m = self.createNode(MissingMachO, name)
-        self.msgout(2, '')
+        self.msgout(2, "")
         return m
 
     def scan_node(self, node):
-        self.msgin(2, 'scan_node', node)
+        self.msgin(2, "scan_node", node)
         for header in node.headers:
-            for idx, name, filename in header.walkRelocatables():
+            for _idx, name, filename in header.walkRelocatables():
                 assert isinstance(name, (str, unicode))
                 assert isinstance(filename, (str, unicode))
                 m = self.load_file(filename, caller=node)
                 self.createReference(node, m, edge_data=name)
-        self.msgout(2, '', node)
+        self.msgout(2, "", node)
 
-    def itergraphreport(self, name='G'):
+    def itergraphreport(self, name="G"):
         nodes = map(self.graph.describe_node, self.graph.iterdfs(self))
         describe_edge = self.graph.describe_edge
         return itergraphreport(nodes, describe_edge, name=name)
@@ -134,5 +137,5 @@ def main(args):
     g.graphreport()
 
 
-if __name__ == '__main__':
-    main(sys.argv[1:] or ['/bin/ls'])
+if __name__ == "__main__":
+    main(sys.argv[1:] or ["/bin/ls"])

lib/spack/external/macholib/MachOStandalone.py

@@ -1,11 +1,17 @@
 import os
-
-from macholib.MachOGraph import MachOGraph, MissingMachO
-from macholib.util import iter_platform_files, in_system_path, mergecopy, \
-    mergetree, flipwritable, has_filename_filter
-from macholib.dyld import framework_info
 from collections import deque
 
+from macholib.dyld import framework_info
+from macholib.MachOGraph import MachOGraph, MissingMachO
+from macholib.util import (
+    flipwritable,
+    has_filename_filter,
+    in_system_path,
+    iter_platform_files,
+    mergecopy,
+    mergetree,
+)
+
 
 class ExcludedMachO(MissingMachO):
     pass
@@ -23,22 +29,20 @@ def createNode(self, cls, name):
 
     def locate(self, filename, loader=None):
         newname = super(FilteredMachOGraph, self).locate(filename, loader)
-        print("locate", filename, loader, "->", newname)
         if newname is None:
             return None
         return self.delegate.locate(newname, loader=loader)
 
 
 class MachOStandalone(object):
-    def __init__(
-            self, base, dest=None, graph=None, env=None,
-            executable_path=None):
-        self.base = os.path.join(os.path.abspath(base), '')
+    def __init__(self, base, dest=None, graph=None, env=None, executable_path=None):
+        self.base = os.path.join(os.path.abspath(base), "")
         if dest is None:
-            dest = os.path.join(self.base, 'Contents', 'Frameworks')
+            dest = os.path.join(self.base, "Contents", "Frameworks")
         self.dest = dest
         self.mm = FilteredMachOGraph(
-            self, graph=graph, env=env, executable_path=executable_path)
+            self, graph=graph, env=env, executable_path=executable_path
+        )
         self.changemap = {}
         self.excludes = []
         self.pending = deque()
@@ -80,8 +84,7 @@ def copy_dylib(self, filename):
         # when two libraries link to the same dylib but using different
         # symlinks.
         if os.path.islink(filename):
-            dest = os.path.join(
-                self.dest, os.path.basename(os.path.realpath(filename)))
+            dest = os.path.join(self.dest, os.path.basename(os.path.realpath(filename)))
         else:
             dest = os.path.join(self.dest, os.path.basename(filename))
 
@@ -96,9 +99,9 @@ def mergetree(self, src, dest):
         return mergetree(src, dest)
 
     def copy_framework(self, info):
-        dest = os.path.join(self.dest, info['shortname'] + '.framework')
-        destfn = os.path.join(self.dest, info['name'])
-        src = os.path.join(info['location'], info['shortname'] + '.framework')
+        dest = os.path.join(self.dest, info["shortname"] + ".framework")
+        destfn = os.path.join(self.dest, info["name"])
+        src = os.path.join(info["location"], info["shortname"] + ".framework")
         if not os.path.exists(dest):
             self.mergetree(src, dest)
             self.pending.append((destfn, iter_platform_files(dest)))
@@ -107,7 +110,7 @@ def copy_framework(self, info):
     def run(self, platfiles=None, contents=None):
         mm = self.mm
         if contents is None:
-            contents = '@executable_path/..'
+            contents = "@executable_path/.."
         if platfiles is None:
             platfiles = iter_platform_files(self.base)
 
@@ -121,18 +124,20 @@ def run(self, platfiles=None, contents=None):
                 mm.run_file(fn, caller=ref)
 
         changemap = {}
-        skipcontents = os.path.join(os.path.dirname(self.dest), '')
+        skipcontents = os.path.join(os.path.dirname(self.dest), "")
         machfiles = []
 
         for node in mm.flatten(has_filename_filter):
             machfiles.append(node)
             dest = os.path.join(
-                contents, os.path.normpath(node.filename[len(skipcontents):]))
+                contents,
+                os.path.normpath(node.filename[len(skipcontents) :]),  # noqa: E203
+            )
             changemap[node.filename] = dest
 
         def changefunc(path):
-            if path.startswith('@loader_path/'):
-                # XXX: This is a quick hack for py2app: In that
+            if path.startswith("@loader_path/"):
+                # This is a quick hack for py2app: In that
                 # usecase paths like this are found in the load
                 # commands of relocatable wheels. Those don't
                 # need rewriting.
@@ -140,9 +145,8 @@ def changefunc(path):
 
             res = mm.locate(path)
             rv = changemap.get(res)
-            if rv is None and path.startswith('@loader_path/'):
-                rv = changemap.get(mm.locate(mm.trans_table.get(
-                        (node.filename, path))))
+            if rv is None and path.startswith("@loader_path/"):
+                rv = changemap.get(mm.locate(mm.trans_table.get((node.filename, path))))
             return rv
 
         for node in machfiles:
@@ -150,14 +154,14 @@ def changefunc(path):
             if fn is None:
                 continue
             rewroteAny = False
-            for header in node.headers:
+            for _header in node.headers:
                 if node.rewriteLoadCommands(changefunc):
                     rewroteAny = True
             if rewroteAny:
                 old_mode = flipwritable(fn)
                 try:
-                    with open(fn, 'rb+') as f:
-                        for header in node.headers:
+                    with open(fn, "rb+") as f:
+                        for _header in node.headers:
                             f.seek(0)
                             node.write(f)
                         f.seek(0, 2)

lib/spack/external/macholib/SymbolTable.py

@@ -3,12 +3,20 @@
 """
 from __future__ import with_statement
 
-from macholib.mach_o import relocation_info, dylib_reference, dylib_module
-from macholib.mach_o import dylib_table_of_contents, nlist, nlist_64
-from macholib.mach_o import MH_CIGAM_64, MH_MAGIC_64
 import sys
 
-__all__ = ['SymbolTable']
+from macholib.mach_o import (
+    MH_CIGAM_64,
+    MH_MAGIC_64,
+    dylib_module,
+    dylib_reference,
+    dylib_table_of_contents,
+    nlist,
+    nlist_64,
+    relocation_info,
+)
+
+__all__ = ["SymbolTable"]
 
 if sys.version_info[0] == 2:
     range = xrange  # noqa: F821
@@ -21,7 +29,7 @@ def __init__(self, macho, header=None, openfile=None):
         if header is None:
             header = macho.headers[0]
         self.macho_header = header
-        with openfile(macho.filename, 'rb') as fh:
+        with openfile(macho.filename, "rb") as fh:
             self.symtab = header.getSymbolTableCommand()
             self.dysymtab = header.getDynamicSymbolTableCommand()
 
@@ -43,22 +51,32 @@ def readSymbolTable(self, fh):
         else:
             cls = nlist
 
-        for i in range(cmd.nsyms):
+        for _i in range(cmd.nsyms):
             cmd = cls.from_fileobj(fh, _endian_=self.macho_header.endian)
             if cmd.n_un == 0:
-                nlists.append((cmd, ''))
+                nlists.append((cmd, ""))
             else:
                 nlists.append(
-                    (cmd, strtab[cmd.n_un:strtab.find(b'\x00', cmd.n_un)]))
+                    (
+                        cmd,
+                        strtab[cmd.n_un : strtab.find(b"\x00", cmd.n_un)],  # noqa: E203
+                    )
+                )
         return nlists
 
     def readDynamicSymbolTable(self, fh):
         cmd = self.dysymtab
         nlists = self.nlists
 
-        self.localsyms = nlists[cmd.ilocalsym:cmd.ilocalsym+cmd.nlocalsym]
-        self.extdefsyms = nlists[cmd.iextdefsym:cmd.iextdefsym+cmd.nextdefsym]
-        self.undefsyms = nlists[cmd.iundefsym:cmd.iundefsym+cmd.nundefsym]
+        self.localsyms = nlists[
+            cmd.ilocalsym : cmd.ilocalsym + cmd.nlocalsym  # noqa: E203
+        ]
+        self.extdefsyms = nlists[
+            cmd.iextdefsym : cmd.iextdefsym + cmd.nextdefsym  # noqa: E203
+        ]
+        self.undefsyms = nlists[
+            cmd.iundefsym : cmd.iundefsym + cmd.nundefsym  # noqa: E203
+        ]
         if cmd.tocoff == 0:
             self.toc = None
         else:
@@ -75,7 +93,7 @@ def readmodtab(self, fh, off, n):
     def readsym(self, fh, off, n):
         fh.seek(self.macho_header.offset + off)
         refs = []
-        for i in range(n):
+        for _i in range(n):
             ref = dylib_reference.from_fileobj(fh)
             isym, flags = divmod(ref.isym_flags, 256)
             refs.append((self.nlists[isym], flags))

lib/spack/external/macholib/__init__.py

@@ -5,4 +5,4 @@
 
 And also Apple's documentation.
 """
-__version__ = '1.10'
+__version__ = "1.15.2"

lib/spack/external/macholib/__main__.py

@@ -1,26 +1,24 @@
-from __future__ import print_function, absolute_import
+from __future__ import absolute_import, print_function
+
 import os
 import sys
 
+from macholib import macho_dump, macho_standalone
 from macholib.util import is_platform_file
-from macholib import macho_dump
-from macholib import macho_standalone
 
 gCommand = None
 
 
 def check_file(fp, path, callback):
     if not os.path.exists(path):
-        print(
-            '%s: %s: No such file or directory' % (gCommand, path),
-            file=sys.stderr)
+        print("%s: %s: No such file or directory" % (gCommand, path), file=sys.stderr)
         return 1
 
     try:
         is_plat = is_platform_file(path)
 
     except IOError as msg:
-        print('%s: %s: %s' % (gCommand, path, msg), file=sys.stderr)
+        print("%s: %s: %s" % (gCommand, path, msg), file=sys.stderr)
         return 1
 
     else:
@@ -34,10 +32,9 @@ def walk_tree(callback, paths):
 
     for base in paths:
         if os.path.isdir(base):
-            for root, dirs, files in os.walk(base):
+            for root, _dirs, files in os.walk(base):
                 for fn in files:
-                    err |= check_file(
-                            sys.stdout, os.path.join(root, fn), callback)
+                    err |= check_file(sys.stdout, os.path.join(root, fn), callback)
         else:
             err |= check_file(sys.stdout, base, callback)
 
@@ -60,17 +57,17 @@ def main():
 
     gCommand = sys.argv[1]
 
-    if gCommand == 'dump':
+    if gCommand == "dump":
         walk_tree(macho_dump.print_file, sys.argv[2:])
 
-    elif gCommand == 'find':
+    elif gCommand == "find":
         walk_tree(lambda fp, path: print(path, file=fp), sys.argv[2:])
 
-    elif gCommand == 'standalone':
+    elif gCommand == "standalone":
         for dn in sys.argv[2:]:
             macho_standalone.standaloneApp(dn)
 
-    elif gCommand in ('help', '--help'):
+    elif gCommand in ("help", "--help"):
         print_usage(sys.stdout)
         sys.exit(0)
 

lib/spack/external/macholib/_cmdline.py

@@ -1,7 +1,8 @@
 """
 Internal helpers for basic commandline tools
 """
-from __future__ import print_function, absolute_import
+from __future__ import absolute_import, print_function
+
 import os
 import sys
 
@@ -10,15 +11,16 @@
 
 def check_file(fp, path, callback):
     if not os.path.exists(path):
-        print('%s: %s: No such file or directory' % (
-            sys.argv[0], path), file=sys.stderr)
+        print(
+            "%s: %s: No such file or directory" % (sys.argv[0], path), file=sys.stderr
+        )
         return 1
 
     try:
         is_plat = is_platform_file(path)
 
     except IOError as msg:
-        print('%s: %s: %s' % (sys.argv[0], path, msg), file=sys.stderr)
+        print("%s: %s: %s" % (sys.argv[0], path, msg), file=sys.stderr)
         return 1
 
     else:
@@ -38,10 +40,9 @@ def main(callback):
 
     for base in args:
         if os.path.isdir(base):
-            for root, dirs, files in os.walk(base):
+            for root, _dirs, files in os.walk(base):
                 for fn in files:
-                    err |= check_file(
-                        sys.stdout, os.path.join(root, fn), callback)
+                    err |= check_file(sys.stdout, os.path.join(root, fn), callback)
         else:
             err |= check_file(sys.stdout, base, callback)
 

lib/spack/external/macholib/dyld.py

@@ -2,18 +2,45 @@
 dyld emulation
 """
 
+import ctypes
+import os
+import platform
+import sys
 from itertools import chain
 
-import os
-import sys
-
-from macholib.framework import framework_info
 from macholib.dylib import dylib_info
+from macholib.framework import framework_info
 
-__all__ = [
-    'dyld_find', 'framework_find',
-    'framework_info', 'dylib_info',
-]
+__all__ = ["dyld_find", "framework_find", "framework_info", "dylib_info"]
+
+if sys.platform == "darwin" and [
+    int(x) for x in platform.mac_ver()[0].split(".")[:2]
+] >= [10, 16]:
+    try:
+        libc = ctypes.CDLL("libSystem.dylib")
+
+    except OSError:
+        _dyld_shared_cache_contains_path = None
+
+    else:
+        try:
+            _dyld_shared_cache_contains_path = libc._dyld_shared_cache_contains_path
+        except AttributeError:
+            _dyld_shared_cache_contains_path = None
+
+        else:
+            _dyld_shared_cache_contains_path.restype = ctypes.c_bool
+            _dyld_shared_cache_contains_path.argtypes = [ctypes.c_char_p]
+
+            if sys.version_info[0] != 2:
+                __dyld_shared_cache_contains_path = _dyld_shared_cache_contains_path
+
+                def _dyld_shared_cache_contains_path(path):
+                    return __dyld_shared_cache_contains_path(path.encode())
+
+
+else:
+    _dyld_shared_cache_contains_path = None
 
 # These are the defaults as per man dyld(1)
 #
@@ -31,13 +58,16 @@
     "/usr/lib",
 ]
 
-# XXX: Is this function still needed?
 if sys.version_info[0] == 2:
+
     def _ensure_utf8(s):
         if isinstance(s, unicode):  # noqa: F821
-            return s.encode('utf8')
+            return s.encode("utf8")
         return s
+
+
 else:
+
     def _ensure_utf8(s):
         if s is not None and not isinstance(s, str):
             raise ValueError(s)
@@ -48,31 +78,31 @@ def _dyld_env(env, var):
     if env is None:
         env = os.environ
     rval = env.get(var)
-    if rval is None or rval == '':
+    if rval is None or rval == "":
         return []
-    return rval.split(':')
+    return rval.split(":")
 
 
 def dyld_image_suffix(env=None):
     if env is None:
         env = os.environ
-    return env.get('DYLD_IMAGE_SUFFIX')
+    return env.get("DYLD_IMAGE_SUFFIX")
 
 
 def dyld_framework_path(env=None):
-    return _dyld_env(env, 'DYLD_FRAMEWORK_PATH')
+    return _dyld_env(env, "DYLD_FRAMEWORK_PATH")
 
 
 def dyld_library_path(env=None):
-    return _dyld_env(env, 'DYLD_LIBRARY_PATH')
+    return _dyld_env(env, "DYLD_LIBRARY_PATH")
 
 
 def dyld_fallback_framework_path(env=None):
-    return _dyld_env(env, 'DYLD_FALLBACK_FRAMEWORK_PATH')
+    return _dyld_env(env, "DYLD_FALLBACK_FRAMEWORK_PATH")
 
 
 def dyld_fallback_library_path(env=None):
-    return _dyld_env(env, 'DYLD_FALLBACK_LIBRARY_PATH')
+    return _dyld_env(env, "DYLD_FALLBACK_LIBRARY_PATH")
 
 
 def dyld_image_suffix_search(iterator, env=None):
@@ -83,8 +113,8 @@ def dyld_image_suffix_search(iterator, env=None):
 
     def _inject(iterator=iterator, suffix=suffix):
         for path in iterator:
-            if path.endswith('.dylib'):
-                yield path[:-len('.dylib')] + suffix + '.dylib'
+            if path.endswith(".dylib"):
+                yield path[: -len(".dylib")] + suffix + ".dylib"
             else:
                 yield path + suffix
             yield path
@@ -102,7 +132,7 @@ def dyld_override_search(name, env=None):
 
     if framework is not None:
         for path in dyld_framework_path(env):
-            yield os.path.join(path, framework['name'])
+            yield os.path.join(path, framework["name"])
 
     # If DYLD_LIBRARY_PATH is set then use the first file that exists
     # in the path.  If none use the original name.
@@ -114,16 +144,18 @@ def dyld_executable_path_search(name, executable_path=None):
     # If we haven't done any searching and found a library and the
     # dylib_name starts with "@executable_path/" then construct the
     # library name.
-    if name.startswith('@executable_path/') and executable_path is not None:
-        yield os.path.join(executable_path, name[len('@executable_path/'):])
+    if name.startswith("@executable_path/") and executable_path is not None:
+        yield os.path.join(
+            executable_path, name[len("@executable_path/") :]  # noqa: E203
+        )
 
 
 def dyld_loader_search(name, loader_path=None):
     # If we haven't done any searching and found a library and the
     # dylib_name starts with "@loader_path/" then construct the
     # library name.
-    if name.startswith('@loader_path/') and loader_path is not None:
-        yield os.path.join(loader_path, name[len('@loader_path/'):])
+    if name.startswith("@loader_path/") and loader_path is not None:
+        yield os.path.join(loader_path, name[len("@loader_path/") :])  # noqa: E203
 
 
 def dyld_default_search(name, env=None):
@@ -136,11 +168,11 @@ def dyld_default_search(name, env=None):
 
         if fallback_framework_path:
             for path in fallback_framework_path:
-                yield os.path.join(path, framework['name'])
+                yield os.path.join(path, framework["name"])
 
         else:
             for path in _DEFAULT_FRAMEWORK_FALLBACK:
-                yield os.path.join(path, framework['name'])
+                yield os.path.join(path, framework["name"])
 
     fallback_library_path = dyld_fallback_library_path(env)
     if fallback_library_path:
@@ -158,12 +190,20 @@ def dyld_find(name, executable_path=None, env=None, loader_path=None):
     """
     name = _ensure_utf8(name)
     executable_path = _ensure_utf8(executable_path)
-    for path in dyld_image_suffix_search(chain(
-                dyld_override_search(name, env),
-                dyld_executable_path_search(name, executable_path),
-                dyld_loader_search(name, loader_path),
-                dyld_default_search(name, env),
-            ), env):
+    for path in dyld_image_suffix_search(
+        chain(
+            dyld_override_search(name, env),
+            dyld_executable_path_search(name, executable_path),
+            dyld_loader_search(name, loader_path),
+            dyld_default_search(name, env),
+        ),
+        env,
+    ):
+        if (
+            _dyld_shared_cache_contains_path is not None
+            and _dyld_shared_cache_contains_path(path)
+        ):
+            return path
         if os.path.isfile(path):
             return path
     raise ValueError("dylib %s could not be found" % (name,))
@@ -182,9 +222,9 @@ def framework_find(fn, executable_path=None, env=None):
         return dyld_find(fn, executable_path=executable_path, env=env)
     except ValueError:
         pass
-    fmwk_index = fn.rfind('.framework')
+    fmwk_index = fn.rfind(".framework")
     if fmwk_index == -1:
         fmwk_index = len(fn)
-        fn += '.framework'
+        fn += ".framework"
     fn = os.path.join(fn, os.path.basename(fn[:fmwk_index]))
     return dyld_find(fn, executable_path=executable_path, env=env)

lib/spack/external/macholib/dylib.py

@@ -4,9 +4,10 @@
 
 import re
 
-__all__ = ['dylib_info']
+__all__ = ["dylib_info"]
 
-_DYLIB_RE = re.compile(r"""(?x)
+_DYLIB_RE = re.compile(
+    r"""(?x)
 (?P<location>^.*)(?:^|/)
 (?P<name>
     (?P<shortname>\w+?)
@@ -14,7 +15,8 @@
     (?:_(?P<suffix>[^._]+))?
     \.dylib$
 )
-""")
+"""
+)
 
 
 def dylib_info(filename):

lib/spack/external/macholib/framework.py

@@ -4,9 +4,10 @@
 
 import re
 
-__all__ = ['framework_info']
+__all__ = ["framework_info"]
 
-_STRICT_FRAMEWORK_RE = re.compile(r"""(?x)
+_STRICT_FRAMEWORK_RE = re.compile(
+    r"""(?x)
 (?P<location>^.*)(?:^|/)
 (?P<name>
     (?P<shortname>[-_A-Za-z0-9]+).framework/
@@ -14,7 +15,8 @@
     (?P=shortname)
     (?:_(?P<suffix>[^_]+))?
 )$
-""")
+"""
+)
 
 
 def framework_info(filename):

lib/spack/external/macholib/itergraphreport.py

@@ -1,7 +1,5 @@
 """
 Utilities for creating dot output from a MachOGraph
-
-XXX: need to rewrite this based on altgraph.Dot
 """
 
 from collections import deque
@@ -11,28 +9,28 @@
 except ImportError:
     imap = map
 
-__all__ = ['itergraphreport']
+__all__ = ["itergraphreport"]
 
 
-def itergraphreport(nodes, describe_edge, name='G'):
+def itergraphreport(nodes, describe_edge, name="G"):
     edges = deque()
     nodetoident = {}
 
     def nodevisitor(node, data, outgoing, incoming):
-        return {'label': str(node)}
+        return {"label": str(node)}
 
     def edgevisitor(edge, data, head, tail):
         return {}
 
-    yield 'digraph %s {\n' % (name,)
-    attr = dict(rankdir='LR', concentrate='true')
+    yield "digraph %s {\n" % (name,)
+    attr = {"rankdir": "LR", "concentrate": "true"}
     cpatt = '%s="%s"'
-    for item in attr.iteritems():
-        yield '\t%s;\n' % (cpatt % item,)
+    for item in attr.items():
+        yield "\t%s;\n" % (cpatt % item,)
 
     # find all packages (subgraphs)
-    for (node, data, outgoing, incoming) in nodes:
-        nodetoident[node] = getattr(data, 'identifier', node)
+    for (node, data, _outgoing, _incoming) in nodes:
+        nodetoident[node] = getattr(data, "identifier", node)
 
     # create sets for subgraph, write out descriptions
     for (node, data, outgoing, incoming) in nodes:
@@ -43,17 +41,19 @@ def edgevisitor(edge, data, head, tail):
         # describe node
         yield '\t"%s" [%s];\n' % (
             node,
-            ','.join([
-                (cpatt % item) for item in
-                nodevisitor(node, data, outgoing, incoming).iteritems()
-            ]),
+            ",".join(
+                [
+                    (cpatt % item)
+                    for item in nodevisitor(node, data, outgoing, incoming).items()
+                ]
+            ),
         )
 
     graph = []
 
     while edges:
         edge, data, head, tail = edges.popleft()
-        if data in ('run_file', 'load_dylib'):
+        if data in ("run_file", "load_dylib"):
             graph.append((edge, data, head, tail))
 
     def do_graph(edges, tabs):
@@ -64,10 +64,10 @@ def do_graph(edges, tabs):
             yield edgestr % (
                 head,
                 tail,
-                ','.join([(cpatt % item) for item in attribs.iteritems()]),
+                ",".join([(cpatt % item) for item in attribs.items()]),
             )
 
-    for s in do_graph(graph, '\t'):
+    for s in do_graph(graph, "\t"):
         yield s
 
-    yield '}\n'
+    yield "}\n"

lib/spack/external/macholib/macho_dump.py

@@ -5,15 +5,14 @@
 import sys
 
 from macholib._cmdline import main as _main
+from macholib.mach_o import CPU_TYPE_NAMES, MH_CIGAM_64, MH_MAGIC_64, get_cpu_subtype
 from macholib.MachO import MachO
-from macholib.mach_o import get_cpu_subtype, CPU_TYPE_NAMES
-from macholib.mach_o import MH_CIGAM_64, MH_MAGIC_64
 
 ARCH_MAP = {
-    ('<', '64-bit'): 'x86_64',
-    ('<', '32-bit'): 'i386',
-    ('>', '64-bit'): 'ppc64',
-    ('>', '32-bit'): 'ppc',
+    ("<", "64-bit"): "x86_64",
+    ("<", "32-bit"): "i386",
+    (">", "64-bit"): "ppc64",
+    (">", "32-bit"): "ppc",
 }
 
 
@@ -24,34 +23,34 @@ def print_file(fp, path):
         seen = set()
 
         if header.MH_MAGIC == MH_MAGIC_64 or header.MH_MAGIC == MH_CIGAM_64:
-            sz = '64-bit'
+            sz = "64-bit"
         else:
-            sz = '32-bit'
+            sz = "32-bit"
 
-        arch = CPU_TYPE_NAMES.get(
-                header.header.cputype, header.header.cputype)
+        arch = CPU_TYPE_NAMES.get(header.header.cputype, header.header.cputype)
 
-        subarch = get_cpu_subtype(
-                header.header.cputype, header.header.cpusubtype)
+        subarch = get_cpu_subtype(header.header.cputype, header.header.cpusubtype)
 
-        print('    [%s endian=%r size=%r arch=%r subarch=%r]' % (
-            header.__class__.__name__, header.endian, sz, arch, subarch),
-            file=fp)
-        for idx, name, other in header.walkRelocatables():
+        print(
+            "    [%s endian=%r size=%r arch=%r subarch=%r]"
+            % (header.__class__.__name__, header.endian, sz, arch, subarch),
+            file=fp,
+        )
+        for _idx, _name, other in header.walkRelocatables():
             if other not in seen:
                 seen.add(other)
-                print('\t' + other, file=fp)
-    print('', file=fp)
+                print("\t" + other, file=fp)
+    print("", file=fp)
 
 
 def main():
     print(
-        "WARNING: 'macho_dump' is deprecated, use 'python -mmacholib dump' "
-        "instead")
+        "WARNING: 'macho_dump' is deprecated, use 'python -mmacholib dump' " "instead"
+    )
     _main(print_file)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     try:
         sys.exit(main())
     except KeyboardInterrupt:

lib/spack/external/macholib/macho_find.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 from __future__ import print_function
+
 from macholib._cmdline import main as _main
 
 
@@ -9,12 +10,12 @@ def print_file(fp, path):
 
 def main():
     print(
-        "WARNING: 'macho_find' is deprecated, "
-        "use 'python -mmacholib dump' instead")
+        "WARNING: 'macho_find' is deprecated, " "use 'python -mmacholib dump' instead"
+    )
     _main(print_file)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     try:
         main()
     except KeyboardInterrupt:

lib/spack/external/macholib/macho_standalone.py

@@ -8,10 +8,8 @@
 
 
 def standaloneApp(path):
-    if not (os.path.isdir(path) and os.path.exists(
-            os.path.join(path, 'Contents'))):
-        print(
-            '%s: %s does not look like an app bundle' % (sys.argv[0], path))
+    if not (os.path.isdir(path) and os.path.exists(os.path.join(path, "Contents"))):
+        print("%s: %s does not look like an app bundle" % (sys.argv[0], path))
         sys.exit(1)
     files = MachOStandalone(path).run()
     strip_files(files)
@@ -20,12 +18,13 @@ def standaloneApp(path):
 def main():
     print(
         "WARNING: 'macho_standalone' is deprecated, use "
-        "'python -mmacholib standalone' instead")
+        "'python -mmacholib standalone' instead"
+    )
     if not sys.argv[1:]:
-        raise SystemExit('usage: %s [appbundle ...]' % (sys.argv[0],))
+        raise SystemExit("usage: %s [appbundle ...]" % (sys.argv[0],))
     for fn in sys.argv[1:]:
         standaloneApp(fn)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()

lib/spack/external/macholib/ptypes.py

@@ -4,12 +4,12 @@
 """
 import struct
 import sys
+from itertools import chain, starmap
 
 try:
-    from itertools import izip, imap
+    from itertools import imap, izip
 except ImportError:
     izip, imap = zip, map
-from itertools import chain, starmap
 
 __all__ = """
 sizeof
@@ -44,7 +44,7 @@ def sizeof(s):
     """
     Return the size of an object when packed
     """
-    if hasattr(s, '_size_'):
+    if hasattr(s, "_size_"):
         return s._size_
 
     elif isinstance(s, bytes):
@@ -58,14 +58,15 @@ class MetaPackable(type):
     Fixed size struct.unpack-able types use from_tuple as their designated
     initializer
     """
+
     def from_mmap(cls, mm, ptr, **kw):
-        return cls.from_str(mm[ptr:ptr+cls._size_], **kw)
+        return cls.from_str(mm[ptr : ptr + cls._size_], **kw)  # noqa: E203
 
     def from_fileobj(cls, f, **kw):
         return cls.from_str(f.read(cls._size_), **kw)
 
     def from_str(cls, s, **kw):
-        endian = kw.get('_endian_', cls._endian_)
+        endian = kw.get("_endian_", cls._endian_)
         return cls.from_tuple(struct.unpack(endian + cls._format_, s), **kw)
 
     def from_tuple(cls, tpl, **kw):
@@ -73,7 +74,7 @@ def from_tuple(cls, tpl, **kw):
 
 
 class BasePackable(object):
-    _endian_ = '>'
+    _endian_ = ">"
 
     def to_str(self):
         raise NotImplementedError
@@ -82,7 +83,7 @@ def to_fileobj(self, f):
         f.write(self.to_str())
 
     def to_mmap(self, mm, ptr):
-        mm[ptr:ptr+self._size_] = self.to_str()
+        mm[ptr : ptr + self._size_] = self.to_str()  # noqa: E203
 
 
 # This defines a class with a custom metaclass, we'd normally
@@ -92,9 +93,10 @@ def to_mmap(self, mm, ptr):
 def _make():
     def to_str(self):
         cls = type(self)
-        endian = getattr(self, '_endian_', cls._endian_)
+        endian = getattr(self, "_endian_", cls._endian_)
         return struct.pack(endian + cls._format_, self)
-    return MetaPackable("Packable", (BasePackable,), {'to_str': to_str})
+
+    return MetaPackable("Packable", (BasePackable,), {"to_str": to_str})
 
 
 Packable = _make()
@@ -109,8 +111,8 @@ def pypackable(name, pytype, format):
     size, items = _formatinfo(format)
 
     def __new__(cls, *args, **kwds):
-        if '_endian_' in kwds:
-            _endian_ = kwds.pop('_endian_')
+        if "_endian_" in kwds:
+            _endian_ = kwds.pop("_endian_")
         else:
             _endian_ = cls._endian_
 
@@ -118,12 +120,11 @@ def __new__(cls, *args, **kwds):
         result._endian_ = _endian_
         return result
 
-    return type(Packable)(name, (pytype, Packable), {
-        '_format_': format,
-        '_size_': size,
-        '_items_': items,
-        '__new__': __new__,
-    })
+    return type(Packable)(
+        name,
+        (pytype, Packable),
+        {"_format_": format, "_size_": size, "_items_": items, "__new__": __new__},
+    )
 
 
 def _formatinfo(format):
@@ -131,7 +132,7 @@ def _formatinfo(format):
     Calculate the size and number of items in a struct format.
     """
     size = struct.calcsize(format)
-    return size, len(struct.unpack(format, b'\x00' * size))
+    return size, len(struct.unpack(format, b"\x00" * size))
 
 
 class MetaStructure(MetaPackable):
@@ -142,17 +143,17 @@ class MetaStructure(MetaPackable):
     we can do a bunch of calculations up front and pack or
     unpack the whole thing in one struct call.
     """
+
     def __new__(cls, clsname, bases, dct):
-        fields = dct['_fields_']
+        fields = dct["_fields_"]
         names = []
         types = []
         structmarks = []
-        format = ''
+        format = ""
         items = 0
         size = 0
 
         def struct_property(name, typ):
-
             def _get(self):
                 return self._objects_[name]
 
@@ -169,16 +170,16 @@ def _set(self, obj):
             types.append(typ)
             format += typ._format_
             size += typ._size_
-            if (typ._items_ > 1):
+            if typ._items_ > 1:
                 structmarks.append((items, typ._items_, typ))
             items += typ._items_
 
-        dct['_structmarks_'] = structmarks
-        dct['_names_'] = names
-        dct['_types_'] = types
-        dct['_size_'] = size
-        dct['_items_'] = items
-        dct['_format_'] = format
+        dct["_structmarks_"] = structmarks
+        dct["_names_"] = names
+        dct["_types_"] = types
+        dct["_size_"] = size
+        dct["_items_"] = items
+        dct["_format_"] = format
         return super(MetaStructure, cls).__new__(cls, clsname, bases, dct)
 
     def from_tuple(cls, tpl, **kw):
@@ -196,7 +197,7 @@ def from_tuple(cls, tpl, **kw):
 # See metaclass discussion earlier in this file
 def _make():
     class_dict = {}
-    class_dict['_fields_'] = ()
+    class_dict["_fields_"] = ()
 
     def as_method(function):
         class_dict[function.__name__] = function
@@ -219,7 +220,7 @@ def __init__(self, *args, **kwargs):
     @as_method
     def _get_packables(self):
         for obj in imap(self._objects_.__getitem__, self._names_):
-            if hasattr(obj, '_get_packables'):
+            if hasattr(obj, "_get_packables"):
                 for obj in obj._get_packables():
                     yield obj
 
@@ -228,18 +229,19 @@ def _get_packables(self):
 
     @as_method
     def to_str(self):
-        return struct.pack(
-            self._endian_ + self._format_, *self._get_packables())
+        return struct.pack(self._endian_ + self._format_, *self._get_packables())
 
     @as_method
     def __cmp__(self, other):
         if type(other) is not type(self):
             raise TypeError(
-                'Cannot compare objects of type %r to objects of type %r' % (
-                    type(other), type(self)))
+                "Cannot compare objects of type %r to objects of type %r"
+                % (type(other), type(self))
+            )
         if sys.version_info[0] == 2:
             _cmp = cmp  # noqa: F821
         else:
+
             def _cmp(a, b):
                 if a < b:
                     return -1
@@ -251,7 +253,8 @@ def _cmp(a, b):
                     raise TypeError()
 
         for cmpval in starmap(
-                _cmp, izip(self._get_packables(), other._get_packables())):
+            _cmp, izip(self._get_packables(), other._get_packables())
+        ):
             if cmpval != 0:
                 return cmpval
         return 0
@@ -289,12 +292,12 @@ def __ge__(self, other):
     @as_method
     def __repr__(self):
         result = []
-        result.append('<')
+        result.append("<")
         result.append(type(self).__name__)
         for nm in self._names_:
-            result.append(' %s=%r' % (nm, getattr(self, nm)))
-        result.append('>')
-        return ''.join(result)
+            result.append(" %s=%r" % (nm, getattr(self, nm)))
+        result.append(">")
+        return "".join(result)
 
     return MetaStructure("Structure", (BasePackable,), class_dict)
 
@@ -308,17 +311,17 @@ def __repr__(self):
     long = int
 
 # export common packables with predictable names
-p_char = pypackable('p_char', bytes, 'c')
-p_int8 = pypackable('p_int8', int, 'b')
-p_uint8 = pypackable('p_uint8', int, 'B')
-p_int16 = pypackable('p_int16', int, 'h')
-p_uint16 = pypackable('p_uint16', int, 'H')
-p_int32 = pypackable('p_int32', int, 'i')
-p_uint32 = pypackable('p_uint32', long, 'I')
-p_int64 = pypackable('p_int64', long, 'q')
-p_uint64 = pypackable('p_uint64', long, 'Q')
-p_float = pypackable('p_float', float, 'f')
-p_double = pypackable('p_double', float, 'd')
+p_char = pypackable("p_char", bytes, "c")
+p_int8 = pypackable("p_int8", int, "b")
+p_uint8 = pypackable("p_uint8", int, "B")
+p_int16 = pypackable("p_int16", int, "h")
+p_uint16 = pypackable("p_uint16", int, "H")
+p_int32 = pypackable("p_int32", int, "i")
+p_uint32 = pypackable("p_uint32", long, "I")
+p_int64 = pypackable("p_int64", long, "q")
+p_uint64 = pypackable("p_uint64", long, "Q")
+p_float = pypackable("p_float", float, "f")
+p_double = pypackable("p_double", float, "d")
 
 # Deprecated names, need trick to emit deprecation warning.
 p_byte = p_int8

lib/spack/external/macholib/util.py

@@ -1,18 +1,18 @@
 import os
-import sys
+import shutil
 import stat
 import struct
-import shutil
+import sys
 
 from macholib import mach_o
 
 MAGIC = [
-    struct.pack('!L', getattr(mach_o, 'MH_' + _))
-    for _ in ['MAGIC', 'CIGAM', 'MAGIC_64', 'CIGAM_64']
+    struct.pack("!L", getattr(mach_o, "MH_" + _))
+    for _ in ["MAGIC", "CIGAM", "MAGIC_64", "CIGAM_64"]
 ]
-FAT_MAGIC_BYTES = struct.pack('!L', mach_o.FAT_MAGIC)
+FAT_MAGIC_BYTES = struct.pack("!L", mach_o.FAT_MAGIC)
 MAGIC_LEN = 4
-STRIPCMD = ['/usr/bin/strip', '-x', '-S', '-']
+STRIPCMD = ["/usr/bin/strip", "-x", "-S", "-"]
 
 try:
     unicode
@@ -20,7 +20,7 @@
     unicode = str
 
 
-def fsencoding(s, encoding=sys.getfilesystemencoding()):
+def fsencoding(s, encoding=sys.getfilesystemencoding()):  # noqa: M511,B008
     """
     Ensure the given argument is in filesystem encoding (not unicode)
     """
@@ -66,16 +66,17 @@ def __init__(self, fileobj, start, size):
         self._end = start + size
 
     def __repr__(self):
-        return '<fileview [%d, %d] %r>' % (
-            self._start, self._end, self._fileobj)
+        return "<fileview [%d, %d] %r>" % (self._start, self._end, self._fileobj)
 
     def tell(self):
         return self._fileobj.tell() - self._start
 
     def _checkwindow(self, seekto, op):
         if not (self._start <= seekto <= self._end):
-            raise IOError("%s to offset %d is outside window [%d, %d]" % (
-                op, seekto, self._start, self._end))
+            raise IOError(
+                "%s to offset %d is outside window [%d, %d]"
+                % (op, seekto, self._start, self._end)
+            )
 
     def seek(self, offset, whence=0):
         seekto = offset
@@ -87,21 +88,22 @@ def seek(self, offset, whence=0):
             seekto += self._end
         else:
             raise IOError("Invalid whence argument to seek: %r" % (whence,))
-        self._checkwindow(seekto, 'seek')
+        self._checkwindow(seekto, "seek")
         self._fileobj.seek(seekto)
 
     def write(self, bytes):
         here = self._fileobj.tell()
-        self._checkwindow(here, 'write')
-        self._checkwindow(here + len(bytes), 'write')
+        self._checkwindow(here, "write")
+        self._checkwindow(here + len(bytes), "write")
         self._fileobj.write(bytes)
 
     def read(self, size=sys.maxsize):
         if size < 0:
             raise ValueError(
-                "Invalid size %s while reading from %s", size, self._fileobj)
+                "Invalid size %s while reading from %s", size, self._fileobj
+            )
         here = self._fileobj.tell()
-        self._checkwindow(here, 'read')
+        self._checkwindow(here, "read")
         bytes = min(size, self._end - here)
         return self._fileobj.read(bytes)
 
@@ -110,8 +112,7 @@ def mergecopy(src, dest):
     """
     copy2, but only if the destination isn't up to date
     """
-    if os.path.exists(dest) and \
-            os.stat(dest).st_mtime >= os.stat(src).st_mtime:
+    if os.path.exists(dest) and os.stat(dest).st_mtime >= os.stat(src).st_mtime:
         return
 
     copy2(src, dest)
@@ -138,13 +139,16 @@ def mergetree(src, dst, condition=None, copyfn=mergecopy, srcbase=None):
             continue
         try:
             if os.path.islink(srcname):
-                # XXX: This is naive at best, should check srcbase(?)
                 realsrc = os.readlink(srcname)
                 os.symlink(realsrc, dstname)
             elif os.path.isdir(srcname):
                 mergetree(
-                    srcname, dstname,
-                    condition=condition, copyfn=copyfn, srcbase=srcbase)
+                    srcname,
+                    dstname,
+                    condition=condition,
+                    copyfn=copyfn,
+                    srcbase=srcbase,
+                )
             else:
                 copyfn(srcname, dstname)
         except (IOError, os.error) as why:
@@ -158,10 +162,10 @@ def sdk_normalize(filename):
     Normalize a path to strip out the SDK portion, normally so that it
     can be decided whether it is in a system path or not.
     """
-    if filename.startswith('/Developer/SDKs/'):
-        pathcomp = filename.split('/')
+    if filename.startswith("/Developer/SDKs/"):
+        pathcomp = filename.split("/")
         del pathcomp[1:4]
-        filename = '/'.join(pathcomp)
+        filename = "/".join(pathcomp)
     return filename
 
 
@@ -173,9 +177,9 @@ def in_system_path(filename):
     Return True if the file is in a system path
     """
     fn = sdk_normalize(os.path.realpath(filename))
-    if fn.startswith('/usr/local/'):
+    if fn.startswith("/usr/local/"):
         return False
-    elif fn.startswith('/System/') or fn.startswith('/usr/'):
+    elif fn.startswith("/System/") or fn.startswith("/usr/"):
         if fn in NOT_SYSTEM_FILES:
             return False
         return True
@@ -187,7 +191,7 @@ def has_filename_filter(module):
     """
     Return False if the module does not have a filename attribute
     """
-    return getattr(module, 'filename', None) is not None
+    return getattr(module, "filename", None) is not None
 
 
 def get_magic():
@@ -204,16 +208,16 @@ def is_platform_file(path):
     if not os.path.exists(path) or os.path.islink(path):
         return False
     # If the header is fat, we need to read into the first arch
-    with open(path, 'rb') as fileobj:
+    with open(path, "rb") as fileobj:
         bytes = fileobj.read(MAGIC_LEN)
         if bytes == FAT_MAGIC_BYTES:
             # Read in the fat header
             fileobj.seek(0)
-            header = mach_o.fat_header.from_fileobj(fileobj, _endian_='>')
+            header = mach_o.fat_header.from_fileobj(fileobj, _endian_=">")
             if header.nfat_arch < 1:
                 return False
             # Read in the first fat arch header
-            arch = mach_o.fat_arch.from_fileobj(fileobj, _endian_='>')
+            arch = mach_o.fat_arch.from_fileobj(fileobj, _endian_=">")
             fileobj.seek(arch.offset)
             # Read magic off the first header
             bytes = fileobj.read(MAGIC_LEN)
@@ -227,7 +231,7 @@ def iter_platform_files(dst):
     """
     Walk a directory and yield each full path that is a Mach-O file
     """
-    for root, dirs, files in os.walk(dst):
+    for root, _dirs, files in os.walk(dst):
         for fn in files:
             fn = os.path.join(root, fn)
             if is_platform_file(fn):
@@ -242,7 +246,7 @@ def strip_files(files, argv_max=(256 * 1024)):
     while tostrip:
         cmd = list(STRIPCMD)
         flips = []
-        pathlen = sum([len(s) + 1 for s in cmd])
+        pathlen = sum(len(s) + 1 for s in cmd)
         while pathlen < argv_max:
             if not tostrip:
                 break

lib/spack/external/py2/typing.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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)
@@ -6,79 +6,98 @@
 This is a fake set of symbols to allow spack to import typing in python
 versions where we do not support type checking (<3)
 """
-Annotated = None
-Any = None
-Callable = None
-ForwardRef = None
-Generic = None
-Literal = None
-Optional = None
-Tuple = None
-TypeVar = None
-Union = None
-AbstractSet = None
-ByteString = None
-Container = None
-Hashable = None
-ItemsView = None
-Iterable = None
-Iterator = None
-KeysView = None
-Mapping = None
-MappingView = None
-MutableMapping = None
-MutableSequence = None
-MutableSet = None
-Sequence = None
-Sized = None
-ValuesView = None
-Awaitable = None
-AsyncIterator = None
-AsyncIterable = None
-Coroutine = None
-Collection = None
-AsyncGenerator = None
-AsyncContextManager = None
-Reversible = None
-SupportsAbs = None
-SupportsBytes = None
-SupportsComplex = None
-SupportsFloat = None
-SupportsInt = None
-SupportsRound = None
-ChainMap = None
-Dict = None
-List = None
-OrderedDict = None
-Set = None
-FrozenSet = None
-NamedTuple = None
-Generator = None
-AnyStr = None
-cast = None
+from collections import defaultdict
+
+# (1) Unparameterized types.
+Annotated = object
+Any = object
+AnyStr = object
+ByteString = object
+Counter = object
+Final = object
+Hashable = object
+NoReturn = object
+Sized = object
+SupportsAbs = object
+SupportsBytes = object
+SupportsComplex = object
+SupportsFloat = object
+SupportsIndex = object
+SupportsInt = object
+SupportsRound = object
+
+# (2) Parameterized types.
+AbstractSet = defaultdict(lambda: object)
+AsyncContextManager = defaultdict(lambda: object)
+AsyncGenerator = defaultdict(lambda: object)
+AsyncIterable = defaultdict(lambda: object)
+AsyncIterator = defaultdict(lambda: object)
+Awaitable = defaultdict(lambda: object)
+Callable = defaultdict(lambda: object)
+ChainMap = defaultdict(lambda: object)
+ClassVar = defaultdict(lambda: object)
+Collection = defaultdict(lambda: object)
+Container = defaultdict(lambda: object)
+ContextManager = defaultdict(lambda: object)
+Coroutine = defaultdict(lambda: object)
+DefaultDict = defaultdict(lambda: object)
+Deque = defaultdict(lambda: object)
+Dict = defaultdict(lambda: object)
+ForwardRef = defaultdict(lambda: object)
+FrozenSet = defaultdict(lambda: object)
+Generator = defaultdict(lambda: object)
+Generic = defaultdict(lambda: object)
+ItemsView = defaultdict(lambda: object)
+Iterable = defaultdict(lambda: object)
+Iterator = defaultdict(lambda: object)
+KeysView = defaultdict(lambda: object)
+List = defaultdict(lambda: object)
+Literal = defaultdict(lambda: object)
+Mapping = defaultdict(lambda: object)
+MappingView = defaultdict(lambda: object)
+MutableMapping = defaultdict(lambda: object)
+MutableSequence = defaultdict(lambda: object)
+MutableSet = defaultdict(lambda: object)
+NamedTuple = defaultdict(lambda: object)
+Optional = defaultdict(lambda: object)
+OrderedDict = defaultdict(lambda: object)
+Reversible = defaultdict(lambda: object)
+Sequence = defaultdict(lambda: object)
+Set = defaultdict(lambda: object)
+Tuple = defaultdict(lambda: object)
+Type = defaultdict(lambda: object)
+TypedDict = defaultdict(lambda: object)
+Union = defaultdict(lambda: object)
+ValuesView = defaultdict(lambda: object)
+
+# (3) Type variable declarations.
+TypeVar = lambda *args, **kwargs: None
+
+# (4) Functions.
+cast = lambda _type, x: x
 get_args = None
 get_origin = None
 get_type_hints = None
 no_type_check = None
 no_type_check_decorator = None
-NoReturn = None
 
-# these are the typing extension symbols
-ClassVar = None
-Final = None
-Protocol = None
-Type = None
-TypedDict = None
-ContextManager = None
-Counter = None
-Deque = None
-DefaultDict = None
-SupportsIndex = None
-final = None
-IntVar = None
-Literal = None
-NewType = None
-overload = None
-runtime_checkable = None
-Text = None
-TYPE_CHECKING = None
+## typing_extensions
+# We get a ModuleNotFoundError when attempting to import anything from typing_extensions
+# if we separate this into a separate typing_extensions.py file for some reason.
+
+# (1) Unparameterized types.
+IntVar = object
+Literal = object
+NewType = object
+Text = object
+
+# (2) Parameterized types.
+Protocol = defaultdict(lambda: object)
+
+# (3) Macro for avoiding evaluation except during type checking.
+TYPE_CHECKING = False
+
+# (4) Decorators.
+final = lambda x: x
+overload = lambda x: x
+runtime_checkable = lambda x: x

lib/spack/llnl/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/llnl/util/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/llnl/util/argparsewriter.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/llnl/util/compat.py

@@ -0,0 +1,39 @@
+# Copyright 2013-2022 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)
+# isort: off
+
+import sys
+
+if sys.version_info < (3,):
+    from itertools import ifilter as filter
+    from itertools import imap as map
+    from itertools import izip as zip
+    from itertools import izip_longest as zip_longest  # novm
+    from urllib import urlencode as urlencode
+    from urllib import urlopen as urlopen
+else:
+    filter = filter
+    map = map
+    zip = zip
+    from itertools import zip_longest as zip_longest  # novm # noqa: F401
+    from urllib.parse import urlencode as urlencode   # novm # noqa: F401
+    from urllib.request import urlopen as urlopen     # novm # noqa: F401
+
+if sys.version_info >= (3, 3):
+    from collections.abc import Hashable as Hashable                # novm
+    from collections.abc import Iterable as Iterable                # novm
+    from collections.abc import Mapping as Mapping                  # novm
+    from collections.abc import MutableMapping as MutableMapping    # novm
+    from collections.abc import MutableSequence as MutableSequence  # novm
+    from collections.abc import MutableSet as MutableSet            # novm
+    from collections.abc import Sequence as Sequence                # novm
+else:
+    from collections import Hashable as Hashable                # noqa: F401
+    from collections import Iterable as Iterable                # noqa: F401
+    from collections import Mapping as Mapping                  # noqa: F401
+    from collections import MutableMapping as MutableMapping    # noqa: F401
+    from collections import MutableSequence as MutableSequence  # noqa: F401
+    from collections import MutableSet as MutableSet            # noqa: F401
+    from collections import Sequence as Sequence                # noqa: F401

lib/spack/llnl/util/filesystem.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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)
@@ -21,15 +21,11 @@
 import six
 
 from llnl.util import tty
+from llnl.util.compat import Sequence
 from llnl.util.lang import dedupe, memoized
 
 from spack.util.executable import Executable
 
-if sys.version_info >= (3, 3):
-    from collections.abc import Sequence  # novm
-else:
-    from collections import Sequence
-
 __all__ = [
     'FileFilter',
     'FileList',
@@ -1642,12 +1638,18 @@ def find_libraries(libraries, root, shared=True, recursive=False):
         raise TypeError(message)
 
     # Construct the right suffix for the library
-    if shared is True:
-        suffix = 'dylib' if sys.platform == 'darwin' else 'so'
+    if shared:
+        # Used on both Linux and macOS
+        suffixes = ['so']
+        if sys.platform == 'darwin':
+            # Only used on macOS
+            suffixes.append('dylib')
     else:
-        suffix = 'a'
+        suffixes = ['a']
+
     # List of libraries we are searching with suffixes
-    libraries = ['{0}.{1}'.format(lib, suffix) for lib in libraries]
+    libraries = ['{0}.{1}'.format(lib, suffix) for lib in libraries
+                 for suffix in suffixes]
 
     if not recursive:
         # If not recursive, look for the libraries directly in root

lib/spack/llnl/util/lang.py

@@ -1,10 +1,11 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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)
 
 from __future__ import division
 
+import contextlib
 import functools
 import inspect
 import os
@@ -12,19 +13,10 @@
 import sys
 from datetime import datetime, timedelta
 
+import six
 from six import string_types
 
-if sys.version_info < (3, 0):
-    from itertools import izip_longest  # novm
-    zip_longest = izip_longest
-else:
-    from itertools import zip_longest  # novm
-
-if sys.version_info >= (3, 3):
-    from collections.abc import Hashable, MutableMapping  # novm
-else:
-    from collections import Hashable, MutableMapping
-
+from llnl.util.compat import MutableMapping, zip_longest
 
 # Ignore emacs backups when listing modules
 ignore_modules = [r'^\.#', '~$']
@@ -174,6 +166,19 @@ def union_dicts(*dicts):
     return result
 
 
+# Used as a sentinel that disambiguates tuples passed in *args from coincidentally
+# matching tuples formed from kwargs item pairs.
+_kwargs_separator = (object(),)
+
+
+def stable_args(*args, **kwargs):
+    """A key factory that performs a stable sort of the parameters."""
+    key = args
+    if kwargs:
+        key += _kwargs_separator + tuple(sorted(kwargs.items()))
+    return key
+
+
 def memoized(func):
     """Decorator that caches the results of a function, storing them in
     an attribute of that function.
@@ -181,15 +186,23 @@ def memoized(func):
     func.cache = {}
 
     @functools.wraps(func)
-    def _memoized_function(*args):
-        if not isinstance(args, Hashable):
-            # Not hashable, so just call the function.
-            return func(*args)
+    def _memoized_function(*args, **kwargs):
+        key = stable_args(*args, **kwargs)
 
-        if args not in func.cache:
-            func.cache[args] = func(*args)
-
-        return func.cache[args]
+        try:
+            return func.cache[key]
+        except KeyError:
+            ret = func(*args, **kwargs)
+            func.cache[key] = ret
+            return ret
+        except TypeError as e:
+            # TypeError is raised when indexing into a dict if the key is unhashable.
+            raise six.raise_from(
+                UnhashableArguments(
+                    "args + kwargs '{}' was not hashable for function '{}'"
+                    .format(key, func.__name__),
+                ),
+                e)
 
     return _memoized_function
 
@@ -931,3 +944,15 @@ def elide_list(line_list, max_num=10):
         return line_list[:max_num - 1] + ['...'] + line_list[-1:]
     else:
         return line_list
+
+
+@contextlib.contextmanager
+def nullcontext(*args, **kwargs):
+    """Empty context manager.
+    TODO: replace with contextlib.nullcontext() if we ever require python 3.7.
+    """
+    yield
+
+
+class UnhashableArguments(TypeError):
+    """Raise when an @memoized function receives unhashable arg or kwarg values."""

lib/spack/llnl/util/link_tree.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/llnl/util/lock.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/llnl/util/multiproc.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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/llnl/util/tty/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Copyright 2013-2022 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)