simmodsuite: depends on rpc

Sun RPC support was optional starting with glibc version 2.26 and was removed in version 2.32. On newer operating systems (e.g., RHEL8) libtirpc is required to satisfy the xdr symbols.

.flake8

@@ -1,25 +1,43 @@
 # -*- conf -*-
-# flake8 settings for Spack.
+# flake8 settings for Spack core files.
 #
 # These exceptions are for Spack core files. We're slightly more lenient
 # with packages.  See .flake8_packages for that.
 #
-# This is the only flake8 rule Spack violates somewhat flagrantly
+# E1: Indentation
+# - E129: visually indented line with same indent as next logical line
+#
+# E2: Whitespace
+# - E221: multiple spaces before operator
+# - E241: multiple spaces after ','
+# - E272: multiple spaces before keyword
+#
+# E7: Statement
 # - E731: do not assign a lambda expression, use a def
 #
-# This is the only flake8 exception needed when using Black.
-# - E203: white space around slice operators can be required, ignore : warn
+# W5: Line break warning
+# - W503: line break before binary operator
+# - W504: line break after binary operator
 #
-# We still allow these in packages (Would like to get rid of them or rely on mypy
-# in the future)
-# - F403: from/import * used; unable to detect undefined names
+# These are required to get the package.py files to test clean:
+# - F999: syntax error in doctest
+#
+# N8: PEP8-naming
+# - N801: class names should use CapWords convention
+# - N813: camelcase imported as lowercase
+# - N814: camelcase imported as constant
+#
+# F4: pyflakes import checks, these are now checked by mypy more precisely
+# - F403: from module import *
 # - F405: undefined name or from *
-# - F821: undefined name (needed with from/import *)
+#
+# Black ignores, these are incompatible with black style and do not follow PEP-8
+# - E203: white space around slice operators can be required, ignore : warn
+# - W503: see above, already ignored for line-breaks
 #
 [flake8]
-#ignore = E129,,W503,W504,F999,N801,N813,N814,F403,F405,E203
-extend-ignore = E731,E203
-max-line-length = 99
+ignore = E129,E221,E241,E272,E731,W503,W504,F999,N801,N813,N814,F403,F405
+max-line-length = 88
 
 # F4: Import
 # - F405: `name` may be undefined, or undefined from star imports: `module`
@@ -28,8 +46,7 @@ max-line-length = 99
 # - F821: undefined name `name`
 #
 per-file-ignores =
-  var/spack/repos/*/package.py:F403,F405,F821
-  *-ci-package.py:F403,F405,F821
+  var/spack/repos/*/package.py:F405,F821
 
 # exclude things we usually do not want linting for.
 # These still get linted when passed explicitly, as when spack flake8 passes

.git-blame-ignore-revs

@@ -1,3 +0,0 @@
-# .git-blame-ignore-revs
-# Formatted entire codebase with black
-f52f6e99dbf1131886a80112b8c79dfc414afb7c

.github/ISSUE_TEMPLATE/test_error.yml

@@ -1,62 +0,0 @@
-name: "\U0001F4A5 Tests error"
-description: Some package in Spack had stand-alone tests that didn't pass
-title: "Testing issue: "
-labels: [test-error]
-body:
-  - type: textarea
-    id: reproduce
-    attributes:
-      label: Steps to reproduce the failure(s) or link(s) to test output(s)
-      description: |
-        Fill in the test output from the exact spec that is having stand-alone test failures. Links to test outputs (e.g., CDash) can also be provided.
-      value: |
-        ```console
-        $ 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 or the test runner
-      description: Please include the output of `spack debug report` for your system.
-    validations:
-      required: true
-  - type: markdown
-    attributes:
-      value: |
-        If you have any relevant configuration detail (custom `packages.yaml` or `modules.yaml`, etc.) you can add that here as well.
-  - type: textarea
-    id: additional_information
-    attributes:
-      label: Additional information
-      description: |
-        Please upload test logs or any additional information about the problem.
-  - type: markdown
-    attributes:
-      value: |
-        Some packages have maintainers who have volunteered to debug build failures. Run `spack maintainers <name-of-the-package>` and **@mention** them here if they exist.
-  - type: checkboxes
-    id: checks
-    attributes:
-      label: General information
-      options:
-        - label: I have reported the version of Spack/Python/Platform/Runner
-          required: true
-        - label: I have run `spack maintainers <name-of-the-package>` and **@mentioned** any maintainers
-          required: true
-        - label: I have uploaded any available logs
-          required: true
-        - label: I have searched the issues of this repo and believe this is not a duplicate
-          required: true

.github/workflows/audit.yaml

@@ -1,44 +0,0 @@
-name: audit
-
-on:
-  workflow_call:
-    inputs:
-      with_coverage:
-        required: true
-        type: string
-      python_version:
-        required: true
-        type: string
-
-concurrency:
-  group: audit-${{inputs.python_version}}-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
-  cancel-in-progress: true
-
-jobs:
-  # Run audits on all the packages in the built-in repository
-  package-audits:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
-      with:
-        python-version: ${{inputs.python_version}}
-    - name: Install Python packages
-      run: |
-        pip install --upgrade pip six setuptools pytest codecov coverage[toml]
-    - name: Package audits (with coverage)
-      if: ${{ inputs.with_coverage == 'true' }}
-      run: |
-          . share/spack/setup-env.sh
-          coverage run $(which spack) audit packages
-          coverage combine
-          coverage xml
-    - name: Package audits (without coverage)
-      if: ${{ inputs.with_coverage == 'false' }}
-      run: |
-          . share/spack/setup-env.sh
-          $(which spack) audit packages
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70 # @v2.1.0
-      if: ${{ inputs.with_coverage == 'true' }}
-      with:
-        flags: unittests,linux,audits

.github/workflows/bootstrap-test.sh

@@ -1,7 +0,0 @@
-#!/bin/bash
-set -ex
-source share/spack/setup-env.sh
-$PYTHON bin/spack bootstrap disable spack-install
-$PYTHON bin/spack -d solve zlib
-tree $BOOTSTRAP/store
-exit 0

.github/workflows/bootstrap.yml

@@ -3,19 +3,33 @@ name: Bootstrapping
 on:
   # This Workflow can be triggered manually
   workflow_dispatch:
-  workflow_call:
+  pull_request:
+    branches:
+      - develop
+      - releases/**
+    paths-ignore:
+      # Don't run if we only modified packages in the
+      # built-in repository or documentation
+      - 'var/spack/repos/builtin/**'
+      - '!var/spack/repos/builtin/packages/clingo-bootstrap/**'
+      - '!var/spack/repos/builtin/packages/clingo/**'
+      - '!var/spack/repos/builtin/packages/python/**'
+      - '!var/spack/repos/builtin/packages/re2c/**'
+      - 'lib/spack/docs/**'
   schedule:
     # nightly at 2:16 AM
     - cron: '16 2 * * *'
 
 concurrency:
-  group: bootstrap-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
   cancel-in-progress: true
 
 jobs:
+
   fedora-clingo-sources:
     runs-on: ubuntu-latest
     container: "fedora:latest"
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         run: |
@@ -24,9 +38,7 @@ jobs:
               make patch unzip which xz python3 python3-devel tree \
               cmake bison bison-devel libstdc++-static
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
-        with:
-          fetch-depth: 0
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Setup non-root user
         run: |
           # See [1] below
@@ -37,13 +49,13 @@ jobs:
         shell: runuser -u spack-test -- bash {0}
         run: |
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap clingo
         shell: runuser -u spack-test -- bash {0}
         run: |
           source share/spack/setup-env.sh
-          spack bootstrap disable github-actions-v0.4
-          spack bootstrap disable github-actions-v0.3
+          spack bootstrap untrust github-actions-v0.2
           spack external find cmake bison
           spack -d solve zlib
           tree ~/.spack/bootstrap/store/
@@ -51,6 +63,7 @@ jobs:
   ubuntu-clingo-sources:
     runs-on: ubuntu-latest
     container: "ubuntu:latest"
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         env:
@@ -62,9 +75,7 @@ jobs:
               make patch unzip xz-utils python3 python3-dev tree \
               cmake bison
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
-        with:
-          fetch-depth: 0
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Setup non-root user
         run: |
           # See [1] below
@@ -75,13 +86,13 @@ jobs:
         shell: runuser -u spack-test -- bash {0}
         run: |
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap clingo
         shell: runuser -u spack-test -- bash {0}
         run: |
           source share/spack/setup-env.sh
-          spack bootstrap disable github-actions-v0.4
-          spack bootstrap disable github-actions-v0.3
+          spack bootstrap untrust github-actions-v0.2
           spack external find cmake bison
           spack -d solve zlib
           tree ~/.spack/bootstrap/store/
@@ -89,6 +100,7 @@ jobs:
   ubuntu-clingo-binaries-and-patchelf:
     runs-on: ubuntu-latest
     container: "ubuntu:latest"
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         env:
@@ -99,9 +111,7 @@ jobs:
               bzip2 curl file g++ gcc gfortran git gnupg2 gzip \
               make patch unzip xz-utils python3 python3-dev tree
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
-        with:
-          fetch-depth: 0
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Setup non-root user
         run: |
           # See [1] below
@@ -112,6 +122,7 @@ jobs:
         shell: runuser -u spack-test -- bash {0}
         run: |
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap clingo
         shell: runuser -u spack-test -- bash {0}
@@ -123,6 +134,7 @@ jobs:
   opensuse-clingo-sources:
     runs-on: ubuntu-latest
     container: "opensuse/leap:latest"
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         run: |
@@ -133,38 +145,36 @@ jobs:
               make patch unzip which xz python3 python3-devel tree \
               cmake bison
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
-        with:
-          fetch-depth: 0
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Setup repo
         run: |
           # See [1] below
           git config --global --add safe.directory /__w/spack/spack
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap clingo
         run: |
           source share/spack/setup-env.sh
-          spack bootstrap disable github-actions-v0.4
-          spack bootstrap disable github-actions-v0.3
+          spack bootstrap untrust github-actions-v0.2
           spack external find cmake bison
           spack -d solve zlib
           tree ~/.spack/bootstrap/store/
 
   macos-clingo-sources:
     runs-on: macos-latest
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         run: |
           brew install cmake bison@2.7 tree
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Bootstrap clingo
         run: |
           source share/spack/setup-env.sh
           export PATH=/usr/local/opt/bison@2.7/bin:$PATH
-          spack bootstrap disable github-actions-v0.4
-          spack bootstrap disable github-actions-v0.3
+          spack bootstrap untrust github-actions-v0.2
           spack external find --not-buildable cmake bison
           spack -d solve zlib
           tree ~/.spack/bootstrap/store/
@@ -173,70 +183,53 @@ jobs:
     runs-on: ${{ matrix.macos-version }}
     strategy:
       matrix:
-        macos-version: ['macos-11', 'macos-12']
+        python-version: ['3.5', '3.6', '3.7', '3.8', '3.9', '3.10']
+        macos-version: ['macos-10.15', 'macos-11', 'macos-12']
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         run: |
           brew install tree
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
+      - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
+        with:
+          python-version: ${{ matrix.python-version }}
       - name: Bootstrap clingo
         run: |
-          set -ex
-          for ver in '3.6' '3.7' '3.8' '3.9' '3.10' ; do
-            not_found=1
-            ver_dir="$(find $RUNNER_TOOL_CACHE/Python -wholename "*/${ver}.*/*/bin" | grep . || true)"
-            echo "Testing $ver_dir"
-            if [[ -d "$ver_dir" ]] ; then
-              if $ver_dir/python --version ; then
-                export PYTHON="$ver_dir/python"
-                not_found=0
-                old_path="$PATH"
-                export PATH="$ver_dir:$PATH"
-                ./bin/spack-tmpconfig -b ./.github/workflows/bootstrap-test.sh
-                export PATH="$old_path"
-              fi
-            fi
-            # NOTE: test all pythons that exist, not all do on 12
-          done
+          source share/spack/setup-env.sh
+          spack bootstrap untrust spack-install
+          spack -d solve zlib
+          tree ~/.spack/bootstrap/store/
 
   ubuntu-clingo-binaries:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ['2.7', '3.5', '3.6', '3.7', '3.8', '3.9', '3.10']
+    if: github.repository == 'spack/spack'
     steps:
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
+      - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
         with:
-          fetch-depth: 0
+          python-version: ${{ matrix.python-version }}
       - name: Setup repo
         run: |
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap clingo
         run: |
-          set -ex
-          for ver in '3.6' '3.7' '3.8' '3.9' '3.10' ; do
-            not_found=1
-            ver_dir="$(find $RUNNER_TOOL_CACHE/Python -wholename "*/${ver}.*/*/bin" | grep . || true)"
-            echo "Testing $ver_dir"
-            if [[ -d "$ver_dir" ]] ; then
-              if $ver_dir/python --version ; then
-                export PYTHON="$ver_dir/python"
-                not_found=0
-                old_path="$PATH"
-                export PATH="$ver_dir:$PATH"
-                ./bin/spack-tmpconfig -b ./.github/workflows/bootstrap-test.sh
-                export PATH="$old_path"
-              fi
-            fi
-            if (($not_found)) ; then
-              echo Required python version $ver not found in runner!
-              exit 1
-            fi
-          done
+          source share/spack/setup-env.sh
+          spack bootstrap untrust spack-install
+          spack -d solve zlib
+          tree ~/.spack/bootstrap/store/
 
   ubuntu-gnupg-binaries:
     runs-on: ubuntu-latest
     container: "ubuntu:latest"
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         env:
@@ -247,9 +240,7 @@ jobs:
               bzip2 curl file g++ gcc patchelf gfortran git gzip \
               make patch unzip xz-utils python3 python3-dev tree
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
-        with:
-          fetch-depth: 0
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Setup non-root user
         run: |
           # See [1] below
@@ -260,18 +251,20 @@ jobs:
         shell: runuser -u spack-test -- bash {0}
         run: |
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap GnuPG
         shell: runuser -u spack-test -- bash {0}
         run: |
           source share/spack/setup-env.sh
-          spack bootstrap disable spack-install
+          spack bootstrap untrust spack-install
           spack -d gpg list
           tree ~/.spack/bootstrap/store/
 
   ubuntu-gnupg-sources:
     runs-on: ubuntu-latest
     container: "ubuntu:latest"
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         env:
@@ -283,9 +276,7 @@ jobs:
               make patch unzip xz-utils python3 python3-dev tree \
               gawk
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
-        with:
-          fetch-depth: 0
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Setup non-root user
         run: |
           # See [1] below
@@ -296,19 +287,20 @@ jobs:
         shell: runuser -u spack-test -- bash {0}
         run: |
           git --version
+          git fetch --unshallow
           . .github/workflows/setup_git.sh
       - name: Bootstrap GnuPG
         shell: runuser -u spack-test -- bash {0}
         run: |
           source share/spack/setup-env.sh
           spack solve zlib
-          spack bootstrap disable github-actions-v0.4
-          spack bootstrap disable github-actions-v0.3
+          spack bootstrap untrust github-actions-v0.2
           spack -d gpg list
           tree ~/.spack/bootstrap/store/
 
   macos-gnupg-binaries:
     runs-on: macos-latest
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         run: |
@@ -316,16 +308,17 @@ jobs:
           # Remove GnuPG since we want to bootstrap it
           sudo rm -rf /usr/local/bin/gpg
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Bootstrap GnuPG
         run: |
           source share/spack/setup-env.sh
-          spack bootstrap disable spack-install
+          spack bootstrap untrust spack-install
           spack -d gpg list
           tree ~/.spack/bootstrap/store/
 
   macos-gnupg-sources:
     runs-on: macos-latest
+    if: github.repository == 'spack/spack'
     steps:
       - name: Install dependencies
         run: |
@@ -333,13 +326,12 @@ jobs:
           # Remove GnuPG since we want to bootstrap it
           sudo rm -rf /usr/local/bin/gpg
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       - name: Bootstrap GnuPG
         run: |
           source share/spack/setup-env.sh
           spack solve zlib
-          spack bootstrap disable github-actions-v0.4
-          spack bootstrap disable github-actions-v0.3
+          spack bootstrap untrust github-actions-v0.2
           spack -d gpg list
           tree ~/.spack/bootstrap/store/
 

.github/workflows/build-containers.yml

@@ -13,14 +13,14 @@ on:
     paths:
       - '.github/workflows/build-containers.yml'
       - 'share/spack/docker/*'
-      - 'share/spack/templates/container/*'
+      - 'share/templates/container/*'
       - 'lib/spack/spack/container/*'
   # Let's also build & tag Spack containers on releases.
   release:
     types: [published]
 
 concurrency:
-  group: build_containers-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
   cancel-in-progress: true
 
 jobs:
@@ -50,7 +50,7 @@ jobs:
     if: github.repository == 'spack/spack'
     steps:
       - name: Checkout
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
 
       - name: Set Container Tag Normal (Nightly)
         run: |
@@ -80,19 +80,19 @@ jobs:
           fi
 
       - name: Upload Dockerfile
-        uses: actions/upload-artifact@83fd05a356d7e2593de66fc9913b3002723633cb
+        uses: actions/upload-artifact@3cea5372237819ed00197afe530f5a7ea3e805c8
         with:
           name: dockerfiles
           path: dockerfiles
 
       - name: Set up QEMU
-        uses: docker/setup-qemu-action@e81a89b1732b9c48d79cd809d8d81d79c4647a18 # @v1
+        uses: docker/setup-qemu-action@8b122486cedac8393e77aa9734c3528886e4a1a8 # @v1
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@8c0edbc76e98fa90f69d9a2c020dcb50019dc325 # @v1
+        uses: docker/setup-buildx-action@dc7b9719a96d48369863986a06765841d7ea23f6 # @v1
 
       - name: Log in to GitHub Container Registry
-        uses: docker/login-action@f4ef78c080cd8ba55a85445d5b36e214a81df20a # @v1
+        uses: docker/login-action@49ed152c8eca782a232dede0303416e8f356c37b # @v1
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
@@ -100,13 +100,13 @@ jobs:
 
       - name: Log in to DockerHub
         if: github.event_name != 'pull_request'
-        uses: docker/login-action@f4ef78c080cd8ba55a85445d5b36e214a81df20a # @v1
+        uses: docker/login-action@49ed152c8eca782a232dede0303416e8f356c37b # @v1
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Build & Deploy ${{ matrix.dockerfile[0] }}
-        uses: docker/build-push-action@c56af957549030174b10d6867f20e78cfd7debc5 # @v2
+        uses: docker/build-push-action@e551b19e49efd4e98792db7592c17c09b89db8d8 # @v2
         with:
           context: dockerfiles/${{ matrix.dockerfile[0] }}
           platforms: ${{ matrix.dockerfile[1] }}

.github/workflows/ci.yaml

@@ -1,86 +0,0 @@
-name: ci
-
-on:
-  push:
-    branches:
-      - develop
-      - releases/**
-  pull_request:
-    branches:
-      - develop
-      - releases/**
-
-concurrency:
-  group: ci-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
-  cancel-in-progress: true
-
-jobs:
-  prechecks:
-    needs: [ changes ]
-    uses: ./.github/workflows/valid-style.yml
-    with:
-      with_coverage: ${{ needs.changes.outputs.core }}
-  all-prechecks:
-    needs: [ prechecks ]
-    runs-on: ubuntu-latest
-    steps:
-    - name: Success
-      run: "true"
-  # Check which files have been updated by the PR
-  changes:
-    runs-on: ubuntu-latest
-      # Set job outputs to values from filter step
-    outputs:
-      bootstrap: ${{ steps.filter.outputs.bootstrap }}
-      core: ${{ steps.filter.outputs.core }}
-      packages: ${{ steps.filter.outputs.packages }}
-    steps:
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
-        if: ${{ github.event_name == 'push' }}
-        with:
-          fetch-depth: 0
-            # For pull requests it's not necessary to checkout the code
-      - uses: dorny/paths-filter@4512585405083f25c027a35db413c2b3b9006d50
-        id: filter
-        with:
-          # See https://github.com/dorny/paths-filter/issues/56 for the syntax used below
-          # Don't run if we only modified packages in the
-          # built-in repository or documentation
-          filters: |
-            bootstrap:
-            - 'var/spack/repos/builtin/packages/clingo-bootstrap/**'
-            - 'var/spack/repos/builtin/packages/clingo/**'
-            - 'var/spack/repos/builtin/packages/python/**'
-            - 'var/spack/repos/builtin/packages/re2c/**'
-            - 'lib/spack/**'
-            - 'share/spack/**'
-            - '.github/workflows/bootstrap.yml'
-            - '.github/workflows/ci.yaml'
-            core:
-            - './!(var/**)/**'
-            packages:
-            - 'var/**'
-      # Some links for easier reference:
-      #
-      # "github" context: https://docs.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions#github-context
-      # job outputs: https://docs.github.com/en/actions/reference/workflow-syntax-for-github-actions#jobsjob_idoutputs
-      # setting environment variables from earlier steps: https://docs.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-environment-variable
-      #
-  bootstrap:
-    if: ${{ github.repository == 'spack/spack' && needs.changes.outputs.bootstrap == 'true' }}
-    needs: [ prechecks, changes ]
-    uses: ./.github/workflows/bootstrap.yml
-  unit-tests:
-    if: ${{ github.repository == 'spack/spack' && needs.changes.outputs.core == 'true' }}
-    needs: [ prechecks, changes ]
-    uses: ./.github/workflows/unit_tests.yaml
-  windows:
-    if: ${{ github.repository == 'spack/spack' && needs.changes.outputs.core == 'true' }}
-    needs: [ prechecks ]
-    uses: ./.github/workflows/windows_python.yml
-  all:
-    needs: [ windows, unit-tests, bootstrap ]
-    runs-on: ubuntu-latest
-    steps:
-    - name: Success
-      run: "true"

.github/workflows/macos_python.yml

@@ -0,0 +1,71 @@
+# These are nightly package tests for macOS
+# focus areas:
+# - initial user experience
+# - scientific python stack
+name: macOS builds nightly
+
+on:
+  schedule:
+    # nightly at 1 AM
+    - cron: '0 1 * * *'
+  pull_request:
+    branches:
+    - develop
+    paths:
+      # Run if we modify this yaml file
+      - '.github/workflows/macos_python.yml'
+      # TODO: run if we touch any of the recipes involved in this
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
+  cancel-in-progress: true
+
+# GitHub Action Limits
+# https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
+
+jobs:
+  install_gcc:
+    name: gcc with clang
+    if: github.repository == 'spack/spack'
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @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@11.2.0 %apple-clang
+
+  install_jupyter_clang:
+    name: jupyter
+    if: github.repository == 'spack/spack'
+    runs-on: macos-latest
+    timeout-minutes: 700
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
+      with:
+        python-version: 3.9
+    - name: spack install
+      run: |
+        . .github/workflows/install_spack.sh
+        spack install -v --fail-fast py-jupyterlab %apple-clang
+
+  install_scipy_clang:
+    name: scipy, mpl, pd
+    if: github.repository == 'spack/spack'
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
+      with:
+        python-version: 3.9
+    - name: spack install
+      run: |
+        . .github/workflows/install_spack.sh
+        spack install -v --fail-fast py-scipy %apple-clang
+        spack install -v --fail-fast py-matplotlib %apple-clang
+        spack install -v --fail-fast py-pandas %apple-clang

.github/workflows/setup_git.ps1

@@ -6,10 +6,6 @@ git config --global user.email "spack@example.com"
 git config --global user.name "Test User"
 git config --global core.longpaths true
 
-# See https://github.com/git/git/security/advisories/GHSA-3wp6-j8xr-qw85 (CVE-2022-39253)
-# This is needed to let some fixture in our unit-test suite run
-git config --global protocol.file.allow always
-
 if ($(git branch --show-current) -ne "develop")
 {
     git branch develop origin/develop

.github/workflows/setup_git.sh

@@ -2,10 +2,6 @@
 git config --global user.email "spack@example.com"
 git config --global user.name "Test User"
 
-# See https://github.com/git/git/security/advisories/GHSA-3wp6-j8xr-qw85 (CVE-2022-39253)
-# This is needed to let some fixture in our unit-test suite run
-git config --global protocol.file.allow always
-
 # create a local pr base branch
 if [[ -n $GITHUB_BASE_REF ]]; then
     git fetch origin "${GITHUB_BASE_REF}:${GITHUB_BASE_REF}"

.github/workflows/unit_tests.yaml

@@ -1,56 +1,120 @@
-name: unit tests
+name: linux tests
 
 on:
-  workflow_dispatch:
-  workflow_call:
+  push:
+    branches:
+      - develop
+      - releases/**
+  pull_request:
+    branches:
+      - develop
+      - releases/**
 
 concurrency:
-  group: unit_tests-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
   cancel-in-progress: true
 
 jobs:
-  # Run unit tests with different configurations on linux
-  ubuntu:
-    runs-on: ${{ matrix.os }}
-    strategy:
-      matrix:
-        os: [ubuntu-latest]
-        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11']
-        concretizer: ['clingo']
-        on_develop:
-        - ${{ github.ref == 'refs/heads/develop' }}
-        include:
-        - python-version: '3.11'
-          os: ubuntu-latest
-          concretizer: original
-          on_develop: ${{ github.ref == 'refs/heads/develop' }}
-        - python-version: '3.6'
-          os: ubuntu-20.04
-          concretizer: clingo
-          on_develop: ${{ github.ref == 'refs/heads/develop' }}
-        exclude:
-        - python-version: '3.7'
-          os: ubuntu-latest
-          concretizer: 'clingo'
-          on_develop: false
-        - python-version: '3.8'
-          os: ubuntu-latest
-          concretizer: 'clingo'
-          on_develop: false
-        - python-version: '3.9'
-          os: ubuntu-latest
-          concretizer: 'clingo'
-          on_develop: false
-        - python-version: '3.10'
-          os: ubuntu-latest
-          concretizer: 'clingo'
-          on_develop: false
-
+  # Validate that the code can be run on all the Python versions
+  # supported by Spack
+  validate:
+    runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
+      with:
+        python-version: '3.10'
+    - name: Install Python Packages
+      run: |
+        pip install --upgrade pip
+        pip install --upgrade vermin
+    - name: vermin (Spack's Core)
+      run: vermin --backport argparse --violations --backport typing -t=2.7- -t=3.5- -vvv lib/spack/spack/ lib/spack/llnl/ bin/
+    - name: vermin (Repositories)
+      run: vermin --backport argparse --violations --backport typing -t=2.7- -t=3.5- -vvv var/spack/repos
+  # Run style checks on the files that have been changed
+  style:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
+      with:
+        python-version: '3.10'
+    - name: Install Python packages
+      run: |
+        pip install --upgrade pip six setuptools types-six
+    - name: Setup git configuration
+      run: |
+        # Need this for the git tests to succeed.
+        git --version
+        . .github/workflows/setup_git.sh
+    - name: Run style tests
+      run: |
+          share/spack/qa/run-style-tests
+  # Check which files have been updated by the PR
+  changes:
+    runs-on: ubuntu-latest
+    # Set job outputs to values from filter step
+    outputs:
+      core: ${{ steps.filter.outputs.core }}
+      packages: ${{ steps.filter.outputs.packages }}
+      with_coverage: ${{ steps.coverage.outputs.with_coverage }}
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+      if: ${{ github.event_name == 'push' }}
+      with:
+        fetch-depth: 0
+    # For pull requests it's not necessary to checkout the code
+    - uses: dorny/paths-filter@b2feaf19c27470162a626bd6fa8438ae5b263721
+      id: filter
+      with:
+        # See https://github.com/dorny/paths-filter/issues/56 for the syntax used below
+        filters: |
+          core:
+          - './!(var/**)/**'
+          packages:
+          - 'var/**'
+    # Some links for easier reference:
+    #
+    # "github" context: https://docs.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions#github-context
+    # job outputs: https://docs.github.com/en/actions/reference/workflow-syntax-for-github-actions#jobsjob_idoutputs
+    # setting environment variables from earlier steps: https://docs.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-environment-variable
+    #
+    - id: coverage
+      # Run the subsequent jobs with coverage if core has been modified,
+      # regardless of whether this is a pull request or a push to a branch
+      run: |
+        echo Core changes: ${{ steps.filter.outputs.core }}
+        echo Event name: ${{ github.event_name }}
+        if [ "${{ steps.filter.outputs.core }}" == "true" ]
+        then
+          echo "::set-output name=with_coverage::true"
+        else
+          echo "::set-output name=with_coverage::false"
+        fi
+
+  # Run unit tests with different configurations on linux
+  unittests:
+    needs: [ validate, style, changes ]
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ['2.7', '3.5', '3.6', '3.7', '3.8', '3.9', '3.10']
+        concretizer: ['clingo']
+        include:
+        - python-version: 2.7
+          concretizer: original
+        - python-version: 3.6
+          concretizer: original
+        - python-version: 3.9
+          concretizer: original
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+      with:
+        fetch-depth: 0
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install System packages
@@ -59,11 +123,19 @@ jobs:
           # Needed for unit tests
           sudo apt-get -y install \
               coreutils cvs gfortran graphviz gnupg2 mercurial ninja-build \
-              cmake bison libbison-dev kcov
+              patchelf cmake bison libbison-dev kcov
     - name: Install Python packages
       run: |
-          pip install --upgrade pip six setuptools pytest codecov[toml] pytest-xdist pytest-cov
-          pip install --upgrade flake8 "isort>=4.3.5" "mypy>=0.900" "click" "black"
+          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.
@@ -75,31 +147,41 @@ jobs:
           SPACK_PYTHON: python
       run: |
           . share/spack/setup-env.sh
-          spack bootstrap disable spack-install
-          spack bootstrap now
+          spack bootstrap untrust spack-install
           spack -v solve zlib
-    - name: Run unit tests
+    - name: Run unit tests (full suite with coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       env:
           SPACK_PYTHON: python
-          SPACK_TEST_SOLVER: ${{ matrix.concretizer }}
-          SPACK_TEST_PARALLEL: 2
           COVERAGE: true
-          UNIT_TEST_COVERAGE: ${{ matrix.python-version == '3.11' }}
+          SPACK_TEST_SOLVER: ${{ matrix.concretizer }}
       run: |
           share/spack/qa/run-unit-tests
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70
+          coverage combine
+          coverage xml
+    - name: Run unit tests (reduced suite without coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'false' }}
+      env:
+          SPACK_PYTHON: python
+          ONLY_PACKAGES: true
+          SPACK_TEST_SOLVER: ${{ matrix.concretizer }}
+      run: |
+          share/spack/qa/run-unit-tests
+    - uses: codecov/codecov-action@81cd2dc8148241f03f5839d295e000b8f761e378 # @v2.1.0
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       with:
         flags: unittests,linux,${{ matrix.concretizer }}
   # Test shell integration
   shell:
+    needs: [ validate, style, changes ]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
       with:
-        python-version: '3.11'
+        python-version: '3.10'
     - name: Install System packages
       run: |
           sudo apt-get -y update
@@ -107,25 +189,33 @@ 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] pytest-xdist
+          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.
           git --version
           . .github/workflows/setup_git.sh
-    - name: Run shell tests
+    - name: Run shell tests (without coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'false' }}
+      run: |
+          share/spack/qa/run-shell-tests
+    - name: Run shell tests (with coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       env:
           COVERAGE: true
       run: |
           share/spack/qa/run-shell-tests
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70
+    - uses: codecov/codecov-action@81cd2dc8148241f03f5839d295e000b8f761e378 # @v2.1.0
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       with:
         flags: shelltests,linux
 
   # Test RHEL8 UBI with platform Python. This job is run
   # only on PRs modifying core Spack
   rhel8-platform-python:
+    needs: [ validate, style, changes ]
     runs-on: ubuntu-latest
+    if: ${{ needs.changes.outputs.with_coverage == 'true' }}
     container: registry.access.redhat.com/ubi8/ubi
     steps:
     - name: Install dependencies
@@ -133,7 +223,7 @@ jobs:
           dnf install -y \
               bzip2 curl file gcc-c++ gcc gcc-gfortran git gnupg2 gzip \
               make patch tcl unzip which xz
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
     - name: Setup repo and non-root user
       run: |
           git --version
@@ -149,67 +239,123 @@ jobs:
           spack unit-test -k 'not cvs and not svn and not hg' -x --verbose
   # Test for the clingo based solver (using clingo-cffi)
   clingo-cffi:
+    needs: [ validate, style, changes ]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
       with:
-        python-version: '3.11'
+        python-version: '3.10'
     - name: Install System packages
       run: |
           sudo apt-get -y update
-          sudo apt-get -y install coreutils cvs gfortran graphviz gnupg2 mercurial ninja-build kcov
+          # Needed for unit tests
+          sudo apt-get -y install \
+              coreutils cvs gfortran graphviz gnupg2 mercurial ninja-build \
+              patchelf kcov
     - name: Install Python packages
       run: |
-          pip install --upgrade pip six setuptools pytest codecov coverage[toml] pytest-cov clingo pytest-xdist
+          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.
           git --version
           . .github/workflows/setup_git.sh
     - name: Run unit tests (full suite with coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       env:
           COVERAGE: true
           SPACK_TEST_SOLVER: clingo
       run: |
           share/spack/qa/run-unit-tests
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70 # @v2.1.0
+          coverage combine
+          coverage xml
+    - name: Run unit tests (reduced suite without coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'false' }}
+      env:
+          ONLY_PACKAGES: true
+          SPACK_TEST_SOLVER: clingo
+      run: |
+          share/spack/qa/run-unit-tests
+    - uses: codecov/codecov-action@81cd2dc8148241f03f5839d295e000b8f761e378 # @v2.1.0
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       with:
         flags: unittests,linux,clingo
   # Run unit tests on MacOS
-  macos:
+  build:
+    needs: [ validate, style, changes ]
     runs-on: macos-latest
     strategy:
       matrix:
-        python-version: ["3.10"]
+        python-version: [3.8]
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @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] pytest-xdist pytest-cov
+          pip install --upgrade pytest codecov coverage[toml]==6.2
     - name: Setup Homebrew packages
       run: |
         brew install dash fish gcc gnupg2 kcov
     - name: Run unit tests
       env:
         SPACK_TEST_SOLVER: clingo
-        SPACK_TEST_PARALLEL: 4
       run: |
         git --version
         . .github/workflows/setup_git.sh
         . share/spack/setup-env.sh
-        $(which spack) bootstrap disable spack-install
+        $(which spack) bootstrap untrust spack-install
         $(which spack) solve zlib
-        common_args=(--dist loadfile --tx '4*popen//python=./bin/spack-tmpconfig python -u ./bin/spack python' -x)
-        $(which spack) unit-test --cov --cov-config=pyproject.toml --cov-report=xml:coverage.xml "${common_args[@]}"
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70
+        if [ "${{ needs.changes.outputs.with_coverage }}" == "true" ]
+        then
+          coverage run $(which spack) unit-test -x
+          coverage combine
+          coverage xml
+          # Delete the symlink going from ./lib/spack/docs/_spack_root back to
+          # the initial directory, since it causes ELOOP errors with codecov/actions@2
+          rm lib/spack/docs/_spack_root
+        else
+          echo "ONLY PACKAGE RECIPES CHANGED [skipping coverage]"
+          $(which spack) unit-test -x -m "not maybeslow" -k "package_sanity"
+        fi
+    - uses: codecov/codecov-action@81cd2dc8148241f03f5839d295e000b8f761e378 # @v2.1.0
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
       with:
+        files: ./coverage.xml
         flags: unittests,macos
+
+  # Run audits on all the packages in the built-in repository
+  package-audits:
+    needs: [ validate, style, changes ]
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # @v2
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08 # @v2
+      with:
+        python-version: '3.10'
+    - name: Install Python packages
+      run: |
+        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: |
+          . share/spack/setup-env.sh
+          coverage run $(which spack) audit packages
+          coverage combine
+          coverage xml
+    - name: Package audits (without coverage)
+      if: ${{ needs.changes.outputs.with_coverage == 'false' }}
+      run: |
+          . share/spack/setup-env.sh
+          $(which spack) audit packages
+    - uses: codecov/codecov-action@81cd2dc8148241f03f5839d295e000b8f761e378 # @v2.1.0
+      if: ${{ needs.changes.outputs.with_coverage == 'true' }}
+      with:
+        flags: unittests,linux,audits

.github/workflows/valid-style.yml

@@ -1,60 +0,0 @@
-name: style
-
-on:
-  workflow_call:
-    inputs:
-      with_coverage:
-        required: true
-        type: string
-
-concurrency:
-  group: style-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
-  cancel-in-progress: true
-
-
-jobs:
-  # Validate that the code can be run on all the Python versions
-  # supported by Spack
-  validate:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
-      with:
-        python-version: '3.11'
-        cache: 'pip'
-    - name: Install Python Packages
-      run: |
-        pip install --upgrade pip
-        pip install --upgrade vermin
-    - name: vermin (Spack's Core)
-      run: vermin --backport importlib --backport argparse --violations --backport typing -t=3.6- -vvv lib/spack/spack/ lib/spack/llnl/ bin/
-    - name: vermin (Repositories)
-      run: vermin --backport importlib --backport argparse --violations --backport typing -t=3.6- -vvv var/spack/repos
-  # Run style checks on the files that have been changed
-  style:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # @v2
-      with:
-        fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # @v2
-      with:
-        python-version: '3.11'
-        cache: 'pip'
-    - name: Install Python packages
-      run: |
-        python3 -m pip install --upgrade pip six setuptools types-six black mypy isort clingo flake8
-    - name: Setup git configuration
-      run: |
-        # Need this for the git tests to succeed.
-        git --version
-        . .github/workflows/setup_git.sh
-    - name: Run style tests
-      run: |
-          share/spack/qa/run-style-tests
-  audit:
-    uses: ./.github/workflows/audit.yaml
-    with:
-      with_coverage: ${{ inputs.with_coverage }}
-      python_version: '3.11'

.github/workflows/windows_python.yml

@@ -1,10 +1,17 @@
-name: windows
+name: windows tests
 
 on:
-  workflow_call:
+  push:
+    branches:
+      - develop
+      - releases/**
+  pull_request:
+    branches:
+      - develop
+      - releases/**
 
 concurrency:
-  group: windows-${{github.ref}}-${{github.event.pull_request.number || github.run_number}}
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
   cancel-in-progress: true
 
 defaults:
@@ -12,64 +19,91 @@ defaults:
     shell:
      powershell Invoke-Expression -Command ".\share\spack\qa\windows_test_setup.ps1"; {0}
 jobs:
-  unit-tests:
+  validate:
     runs-on: windows-latest
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
+      with:
+        python-version: 3.9
+    - name: Install Python Packages
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install --upgrade vermin
+    - name: vermin (Spack's Core)
+      run: vermin --backport argparse --backport typing -t='2.7-' -t='3.5-' -v spack/lib/spack/spack/ spack/lib/spack/llnl/ spack/bin/
+    - name: vermin (Repositories)
+      run: vermin --backport argparse --backport typing -t='2.7-' -t='3.5-' -v spack/var/spack/repos
+  # Run style checks on the files that have been changed
+  style:
+    runs-on: windows-latest
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
       with:
         python-version: 3.9
     - name: Install Python packages
       run: |
-          python -m pip install --upgrade pip six pywin32 setuptools codecov pytest-cov clingo
+        python -m pip install --upgrade pip six setuptools flake8 isort>=4.3.5 mypy>=0.800 black pywin32 types-python-dateutil
+    - name: Create local develop
+      run: |
+        .\spack\.github\workflows\setup_git.ps1
+    - name: Run style tests
+      run: |
+        spack style
+    - name: Verify license headers
+      run: |
+        python spack\bin\spack license verify
+  unittest:
+    needs: [ validate, style ]
+    runs-on: windows-latest
+    steps:
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
+      with:
+        fetch-depth: 0
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
+      with:
+        python-version: 3.9
+    - name: Install Python packages
+      run: |
+          python -m pip install --upgrade pip six pywin32 setuptools codecov coverage
     - name: Create local develop
       run: |
         .\spack\.github\workflows\setup_git.ps1
     - name: Unit Test
       run: |
         echo F|xcopy .\spack\share\spack\qa\configuration\windows_config.yaml $env:USERPROFILE\.spack\windows\config.yaml
-        cd spack
-        dir
-        spack unit-test -x --verbose --cov --cov-config=pyproject.toml --ignore=lib/spack/spack/test/cmd
-        coverage combine -a
-        coverage xml
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70
-      with:
-        flags: unittests,windows
-  unit-tests-cmd:
+        spack unit-test --verbose --ignore=lib/spack/spack/test/cmd
+  unittest-cmd:
+    needs: [ validate, style ]
     runs-on: windows-latest
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
       with:
         python-version: 3.9
     - name: Install Python packages
       run: |
-          python -m pip install --upgrade pip six pywin32 setuptools codecov coverage pytest-cov clingo
+          python -m pip install --upgrade pip six pywin32 setuptools codecov coverage
     - name: Create local develop
       run: |
         .\spack\.github\workflows\setup_git.ps1
     - name: Command Unit Test
       run: |
         echo F|xcopy .\spack\share\spack\qa\configuration\windows_config.yaml $env:USERPROFILE\.spack\windows\config.yaml
-        cd spack
-        spack unit-test -x --verbose --cov --cov-config=pyproject.toml lib/spack/spack/test/cmd
-        coverage combine -a
-        coverage xml
-    - uses: codecov/codecov-action@d9f34f8cd5cb3b3eb79b3e4b5dae3a16df499a70
-      with:
-        flags: unittests,windows
-  build-abseil:
+        spack unit-test lib/spack/spack/test/cmd --verbose
+  buildtest:
+    needs: [ validate, style ]
     runs-on: windows-latest
     steps:
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
       with:
         python-version: 3.9
     - name: Install Python packages
@@ -81,8 +115,9 @@ jobs:
         echo F|xcopy .\spack\share\spack\qa\configuration\windows_config.yaml $env:USERPROFILE\.spack\windows\config.yaml
         spack external find cmake
         spack external find ninja
-        spack -d install abseil-cpp
-  make-installer:
+        spack install abseil-cpp
+  generate-installer-test:
+    needs: [ validate, style ]
     runs-on: windows-latest
     steps:
     - name: Disable Windows Symlinks
@@ -90,15 +125,15 @@ jobs:
         git config --global core.symlinks false
       shell:
         powershell
-    - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8
+    - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
       with:
         python-version: 3.9
     - name: Install Python packages
       run: |
-          python -m pip install --upgrade pip six pywin32 setuptools
+          python -m pip install --upgrade pip six pywin32 setuptools codecov coverage
     - name: Add Light and Candle to Path
       run: |
         $env:WIX >> $GITHUB_PATH
@@ -109,27 +144,27 @@ jobs:
         echo "installer_root=$((pwd).Path)" | Out-File -FilePath $Env:GITHUB_ENV -Encoding utf8 -Append
       env:
         ProgressPreference: SilentlyContinue
-    - uses: actions/upload-artifact@83fd05a356d7e2593de66fc9913b3002723633cb
+    - uses: actions/upload-artifact@3cea5372237819ed00197afe530f5a7ea3e805c8
       with:
         name: Windows Spack Installer Bundle
         path: ${{ env.installer_root }}\pkg\Spack.exe
-    - uses: actions/upload-artifact@83fd05a356d7e2593de66fc9913b3002723633cb
+    - uses: actions/upload-artifact@3cea5372237819ed00197afe530f5a7ea3e805c8
       with:
         name: Windows Spack Installer
         path: ${{ env.installer_root}}\pkg\Spack.msi
   execute-installer:
-    needs: make-installer
+    needs: generate-installer-test
     runs-on: windows-latest
     defaults:
       run:
         shell: pwsh
     steps:
-    - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984
+    - uses: actions/setup-python@c4e89fac7e8767b327bbad6cb4d859eda999cf08
       with:
         python-version: 3.9
     - name: Install Python packages
       run: |
-          python -m pip install --upgrade pip six pywin32 setuptools
+          python -m pip install --upgrade pip six pywin32 setuptools codecov coverage
     - name: Setup installer directory
       run: |
         mkdir -p spack_installer
@@ -155,4 +190,4 @@ jobs:
         $proc = Start-Process  ${{ env.spack_installer }}\spack.msi "/quiet" -Passthru
         $handle = $proc.Handle # cache proc.Handle
         $proc.WaitForExit();
-        $LASTEXITCODE
+        $LASTEXITCODE

CHANGELOG.md

@@ -1,289 +1,3 @@
-# v0.19.0 (2022-11-11)
-
-`v0.19.0` is a major feature release.
-
-## Major features in this release
-
-1. **Package requirements**
-
-   Spack's traditional [package preferences](
-     https://spack.readthedocs.io/en/latest/build_settings.html#package-preferences)
-   are soft, but we've added hard requriements to `packages.yaml` and `spack.yaml`
-   (#32528, #32369). Package requirements use the same syntax as specs:
-
-   ```yaml
-   packages:
-     libfabric:
-       require: "@1.13.2"
-     mpich:
-       require:
-       - one_of: ["+cuda", "+rocm"]
-   ```
-
-   More details in [the docs](
-     https://spack.readthedocs.io/en/latest/build_settings.html#package-requirements).
-
-2. **Environment UI Improvements**
-
-   * Fewer surprising modifications to `spack.yaml` (#33711):
-
-     * `spack install` in an environment will no longer add to the `specs:` list; you'll
-       need to either use `spack add <spec>` or `spack install --add <spec>`.
-
-     * Similarly, `spack uninstall` will not remove from your environment's `specs:`
-       list; you'll need to use `spack remove` or `spack uninstall --remove`.
-
-     This will make it easier to manage an environment, as there is clear separation
-     between the stack to be installed (`spack.yaml`/`spack.lock`) and which parts of
-     it should be installed (`spack install` / `spack uninstall`).
-
-   * `concretizer:unify:true` is now the default mode for new environments (#31787)
-
-     We see more users creating `unify:true` environments now. Users who need
-     `unify:false` can add it to their environment to get the old behavior. This will
-     concretize every spec in the environment independently.
-
-   * Include environment configuration from URLs (#29026, [docs](
-       https://spack.readthedocs.io/en/latest/environments.html#included-configurations))
-
-     You can now include configuration in your environment directly from a URL:
-
-     ```yaml
-     spack:
-       include:
-       - https://github.com/path/to/raw/config/compilers.yaml
-     ```
-
-4. **Multiple Build Systems**
-
-   An increasing number of packages in the ecosystem need the ability to support
-   multiple build systems (#30738, [docs](
-     https://spack.readthedocs.io/en/latest/packaging_guide.html#multiple-build-systems)),
-   either across versions, across platforms, or within the same version of the software.
-   This has been hard to support through multiple inheritance, as methods from different
-   build system superclasses would conflict. `package.py` files can now define separate
-   builder classes with installation logic for different build systems, e.g.:
-
-   ```python
-   class ArpackNg(CMakePackage, AutotoolsPackage):
-
-       build_system(
-           conditional("cmake", when="@0.64:"),
-           conditional("autotools", when="@:0.63"),
-           default="cmake",
-       )
-
-   class CMakeBuilder(spack.build_systems.cmake.CMakeBuilder):
-       def cmake_args(self):
-           pass
-
-   class Autotoolsbuilder(spack.build_systems.autotools.AutotoolsBuilder):
-       def configure_args(self):
-           pass
-   ```
-
-5. **Compiler and variant propagation**
-
-   Currently, compiler flags and variants are inconsistent: compiler flags set for a
-   package are inherited by its dependencies, while variants are not. We should have
-   these be consistent by allowing for inheritance to be enabled or disabled for both
-   variants and compiler flags.
-
-   Example syntax:
-   - `package ++variant`:
-         enabled variant that will be propagated to dependencies
-   - `package +variant`:
-         enabled variant that will NOT be propagated to dependencies
-   - `package ~~variant`:
-         disabled variant that will be propagated to dependencies
-   - `package ~variant`:
-         disabled variant that will NOT be propagated to dependencies
-   - `package cflags==-g`:
-         `cflags` will be propagated to dependencies
-   - `package cflags=-g`:
-         `cflags` will NOT be propagated to dependencies
-
-   Syntax for non-boolan variants is similar to compiler flags. More in the docs for
-   [variants](
-     https://spack.readthedocs.io/en/latest/basic_usage.html#variants) and [compiler flags](
-     https://spack.readthedocs.io/en/latest/basic_usage.html#compiler-flags).
-
-6. **Enhancements to git version specifiers**
-
-   * `v0.18.0` added the ability to use git commits as versions. You can now use the
-     `git.` prefix to specify git tags or branches as versions. All of these are valid git
-     versions in `v0.19` (#31200):
-
-     ```console
-     foo@abcdef1234abcdef1234abcdef1234abcdef1234      # raw commit
-     foo@git.abcdef1234abcdef1234abcdef1234abcdef1234  # commit with git prefix
-     foo@git.develop                                   # the develop branch
-     foo@git.0.19                                      # use the 0.19 tag
-     ```
-
-   * `v0.19` also gives you more control over how Spack interprets git versions, in case
-     Spack cannot detect the version from the git repository. You can suffix a git
-     version with `=<version>` to force Spack to concretize it as a particular version
-     (#30998, #31914, #32257):
-
-     ```console
-     # use mybranch, but treat it as version 3.2 for version comparison
-     foo@git.mybranch=3.2
-
-     # use the given commit, but treat it as develop for version comparison
-     foo@git.abcdef1234abcdef1234abcdef1234abcdef1234=develop
-     ```
-
-     More in [the docs](
-       https://spack.readthedocs.io/en/latest/basic_usage.html#version-specifier)
-
-7. **Changes to Cray EX Support**
-
-   Cray machines have historically had their own "platform" within Spack, because we
-   needed to go through the module system to leverage compilers and MPI installations on
-   these machines. The Cray EX programming environment now provides standalone `craycc`
-   executables and proper `mpicc` wrappers, so Spack can treat EX machines like Linux
-   with extra packages (#29392).
-
-   We expect this to greatly reduce bugs, as external packages and compilers can now be
-   used by prefix instead of through modules. We will also no longer be subject to
-   reproducibility issues when modules change from Cray PE release to release and from
-   site to site. This also simplifies dealing with the underlying Linux OS on cray
-   systems, as Spack will properly model the machine's OS as either SuSE or RHEL.
-
-8. **Improvements to tests and testing in CI**
-
-   * `spack ci generate --tests` will generate a `.gitlab-ci.yml` file that not only does
-     builds but also runs tests for built packages (#27877). Public GitHub pipelines now
-     also run tests in CI.
-
-   * `spack test run --explicit` will only run tests for packages that are explicitly
-     installed, instead of all packages.
-
-9. **Experimental binding link model**
-
-   You can add a new option to `config.yaml` to make Spack embed absolute paths to
-   needed shared libraries in ELF executables and shared libraries on Linux (#31948, [docs](
-     https://spack.readthedocs.io/en/latest/config_yaml.html#shared-linking-bind)):
-
-   ```yaml
-   config:
-     shared_linking:
-       type: rpath
-       bind: true
-   ```
-
-   This can improve launch time at scale for parallel applications, and it can make
-   installations less susceptible to environment variables like `LD_LIBRARY_PATH`, even
-   especially when dealing with external libraries that use `RUNPATH`. You can think of
-   this as a faster, even higher-precedence version of `RPATH`.
-
-## Other new features of note
-
-* `spack spec` prints dependencies more legibly. Dependencies in the output now appear
-  at the *earliest* level of indentation possible (#33406)
-* You can override `package.py` attributes like `url`, directly in `packages.yaml`
-  (#33275, [docs](
-    https://spack.readthedocs.io/en/latest/build_settings.html#assigning-package-attributes))
-* There are a number of new architecture-related format strings you can use in Spack
-  configuration files to specify paths (#29810, [docs](
-    https://spack.readthedocs.io/en/latest/configuration.html#config-file-variables))
-* Spack now supports bootstrapping Clingo on Windows (#33400)
-* There is now support for an `RPATH`-like library model on Windows (#31930)
-
-## Performance Improvements
-
-* Major performance improvements for installation from binary caches (#27610, #33628,
-  #33636, #33608, #33590, #33496)
-* Test suite can now be parallelized using `xdist` (used in GitHub Actions) (#32361)
-* Reduce lock contention for parallel builds in environments (#31643)
-
-## New binary caches and stacks
-
-* We now build nearly all of E4S with `oneapi` in our buildcache (#31781, #31804,
-  #31804, #31803, #31840, #31991, #32117, #32107, #32239)
-* Added 3 new machine learning-centric stacks to binary cache: `x86_64_v3`, CUDA, ROCm
-  (#31592, #33463)
-
-## Removals and Deprecations
-
-* Support for Python 3.5 is dropped (#31908). Only Python 2.7 and 3.6+ are officially
-  supported.
-
-* This is the last Spack release that will support Python 2 (#32615). Spack `v0.19`
-  will emit a deprecation warning if you run it with Python 2, and Python 2 support will
-  soon be removed from the `develop` branch.
-
-* `LD_LIBRARY_PATH` is no longer set by default by `spack load` or module loads.
-
-  Setting `LD_LIBRARY_PATH` in Spack environments/modules can cause binaries from
-  outside of Spack to crash, and Spack's own builds use `RPATH` and do not need
-  `LD_LIBRARY_PATH` set in order to run. If you still want the old behavior, you
-  can run these commands to configure Spack to set `LD_LIBRARY_PATH`:
-
-  ```console
-  spack config add modules:prefix_inspections:lib64:[LD_LIBRARY_PATH]
-  spack config add modules:prefix_inspections:lib:[LD_LIBRARY_PATH]
-  ```
-
-* The `spack:concretization:[together|separately]` has been removed after being
-  deprecated in `v0.18`. Use `concretizer:unify:[true|false]`.
-* `config:module_roots` is no longer supported after being deprecated in `v0.18`. Use
-  configuration in module sets instead (#28659, [docs](
-    https://spack.readthedocs.io/en/latest/module_file_support.html)).
-* `spack activate` and `spack deactivate` are no longer supported, having been
-  deprecated in `v0.18`. Use an environment with a view instead of
-  activating/deactivating ([docs](
-    https://spack.readthedocs.io/en/latest/environments.html#configuration-in-spack-yaml)).
-* The old YAML format for buildcaches is now deprecated (#33707). If you are using an
-  old buildcache with YAML metadata you will need to regenerate it with JSON metadata.
-* `spack bootstrap trust` and `spack bootstrap untrust` are deprecated in favor of
-  `spack bootstrap enable` and `spack bootstrap disable` and will be removed in `v0.20`.
-  (#33600)
-* The `graviton2` architecture has been renamed to `neoverse_n1`, and `graviton3`
-  is now `neoverse_v1`. Buildcaches using the old architecture names will need to be rebuilt.
-* The terms `blacklist` and `whitelist` have been replaced with `include` and `exclude`
-  in all configuration files (#31569). You can use `spack config update` to
-  automatically fix your configuration files.
-
-## Notable Bugfixes
-
-* Permission setting on installation now handles effective uid properly (#19980)
-* `buildable:true` for an MPI implementation now overrides `buildable:false` for `mpi` (#18269)
-* Improved error messages when attempting to use an unconfigured compiler (#32084)
-* Do not punish explicitly requested compiler mismatches in the solver (#30074)
-* `spack stage`: add missing --fresh and --reuse (#31626)
-* Fixes for adding build system executables like `cmake` to package scope (#31739)
-* Bugfix for binary relocation with aliased strings produced by newer `binutils` (#32253)
-
-## Spack community stats
-
-* 6,751 total packages, 335 new since `v0.18.0`
-    * 141 new Python packages
-    * 89 new R packages
-* 303 people contributed to this release
-    * 287 committers to packages
-    * 57 committers to core
-
-
-# v0.18.1 (2022-07-19)
-
-### Spack Bugfixes
-* Fix several bugs related to bootstrapping (#30834,#31042,#31180)
-* Fix a regression that was causing spec hashes to differ between
-  Python 2 and Python 3 (#31092)
-* Fixed compiler flags for oneAPI and DPC++ (#30856)
-* Fixed several issues related to concretization (#31142,#31153,#31170,#31226)
-* Improved support for Cray manifest file and `spack external find` (#31144,#31201,#31173,#31186)
-* Assign a version to openSUSE Tumbleweed according to the GLIBC version
-  in the system (#19895)
-* Improved Dockerfile generation for `spack containerize` (#29741,#31321)
-* Fixed a few bugs related to concurrent execution of commands (#31509,#31493,#31477)
-
-### Package updates
-* WarpX: add v22.06, fixed libs property (#30866,#31102)
-* openPMD: add v0.14.5, update recipe for @develop (#29484,#31023)
-
 # v0.18.0 (2022-05-28)
 
 `v0.18.0` is a major feature release.
@@ -485,15 +199,6 @@
     * 337 committers to packages
     * 85 committers to core
 
-# v0.17.3 (2022-07-14)
-
-### Spack bugfixes
-
-* Fix missing chgrp on symlinks in package installations (#30743)
-* Allow having non-existing upstreams (#30744, #30746)
-* Fix `spack stage` with custom paths (#30448)
-* Fix failing call for `spack buildcache save-specfile` (#30637)
-* Fix globbing in compiler wrapper (#30699)
 
 # v0.17.2 (2022-04-13)
 

README.md

@@ -2,10 +2,10 @@
 
 [![Unit Tests](https://github.com/spack/spack/workflows/linux%20tests/badge.svg)](https://github.com/spack/spack/actions)
 [![Bootstrapping](https://github.com/spack/spack/actions/workflows/bootstrap.yml/badge.svg)](https://github.com/spack/spack/actions/workflows/bootstrap.yml)
+[![macOS Builds (nightly)](https://github.com/spack/spack/workflows/macOS%20builds%20nightly/badge.svg?branch=develop)](https://github.com/spack/spack/actions?query=workflow%3A%22macOS+builds+nightly%22)
 [![codecov](https://codecov.io/gh/spack/spack/branch/develop/graph/badge.svg)](https://codecov.io/gh/spack/spack)
 [![Containers](https://github.com/spack/spack/actions/workflows/build-containers.yml/badge.svg)](https://github.com/spack/spack/actions/workflows/build-containers.yml)
 [![Read the Docs](https://readthedocs.org/projects/spack/badge/?version=latest)](https://spack.readthedocs.io)
-[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 [![Slack](https://slack.spack.io/badge.svg)](https://slack.spack.io)
 
 Spack is a multi-platform package manager that builds and installs
@@ -62,7 +62,6 @@ Resources:
 
 * **Slack workspace**: [spackpm.slack.com](https://spackpm.slack.com).
   To get an invitation, visit [slack.spack.io](https://slack.spack.io).
-* [**Github Discussions**](https://github.com/spack/spack/discussions): not just for discussions, also Q&A.
 * **Mailing list**: [groups.google.com/d/forum/spack](https://groups.google.com/d/forum/spack)
 * **Twitter**: [@spackpm](https://twitter.com/spackpm). Be sure to
   `@mention` us!

SECURITY.md

@@ -10,8 +10,8 @@ For more on Spack's release structure, see
 | Version | Supported          |
 | ------- | ------------------ |
 | develop | :white_check_mark: |
-| 0.19.x  | :white_check_mark: |
-| 0.18.x  | :white_check_mark: |
+| 0.17.x  | :white_check_mark: |
+| 0.16.x  | :white_check_mark: |
 
 ## Reporting a Vulnerability
 

bin/haspywin.py

@@ -8,11 +8,13 @@
 
 def getpywin():
     try:
-        import win32con  # noqa: F401
+        import win32con  # noqa
     except ImportError:
-        subprocess.check_call([sys.executable, "-m", "pip", "-q", "install", "--upgrade", "pip"])
-        subprocess.check_call([sys.executable, "-m", "pip", "-q", "install", "pywin32"])
+        subprocess.check_call(
+            [sys.executable, "-m", "pip", "-q", "install", "--upgrade", "pip"])
+        subprocess.check_call(
+            [sys.executable, "-m", "pip", "-q", "install", "pywin32"])
 
 
-if __name__ == "__main__":
+if __name__ == '__main__':
     getpywin()

bin/spack

@@ -31,11 +31,13 @@ import os
 import os.path
 import sys
 
-min_python3 = (3, 6)
+min_python3 = (3, 5)
 
-if sys.version_info[:2] < min_python3:
+if sys.version_info[:2] < (2, 7) or (
+    sys.version_info[:2] >= (3, 0) and sys.version_info[:2] < min_python3
+):
     v_info = sys.version_info[:3]
-    msg = "Spack requires Python %d.%d or higher " % min_python3
+    msg = "Spack requires Python 2.7 or %d.%d or higher " % min_python3
     msg += "You are running spack with Python %d.%d.%d." % v_info
     sys.exit(msg)
 
@@ -47,8 +49,50 @@ spack_prefix = os.path.dirname(os.path.dirname(spack_file))
 spack_lib_path = os.path.join(spack_prefix, "lib", "spack")
 sys.path.insert(0, spack_lib_path)
 
-from spack_installable.main import main  # noqa: E402
+# Add external libs
+spack_external_libs = os.path.join(spack_lib_path, "external")
+
+if sys.version_info[:2] <= (2, 7):
+    sys.path.insert(0, os.path.join(spack_external_libs, "py2"))
+
+sys.path.insert(0, spack_external_libs)
+
+# Here we delete ruamel.yaml in case it has been already imported from site
+# (see #9206 for a broader description of the issue).
+#
+# Briefly: ruamel.yaml produces a .pth file when installed with pip that
+# makes the site installed package the preferred one, even though sys.path
+# is modified to point to another version of ruamel.yaml.
+if "ruamel.yaml" in sys.modules:
+    del sys.modules["ruamel.yaml"]
+
+if "ruamel" in sys.modules:
+    del sys.modules["ruamel"]
+
+# The following code is here to avoid failures when updating
+# the develop version, due to spurious argparse.pyc files remaining
+# in the libs/spack/external directory, see:
+# https://github.com/spack/spack/pull/25376
+# TODO: Remove in v0.18.0 or later
+try:
+    import argparse
+except ImportError:
+    argparse_pyc = os.path.join(spack_external_libs, 'argparse.pyc')
+    if not os.path.exists(argparse_pyc):
+        raise
+    try:
+        os.remove(argparse_pyc)
+        import argparse  # noqa
+    except Exception:
+        msg = ('The file\n\n\t{0}\n\nis corrupted and cannot be deleted by Spack. '
+               'Either delete it manually or ask some administrator to '
+               'delete it for you.')
+        print(msg.format(argparse_pyc))
+        sys.exit(1)
+
+
+import spack.main  # noqa
 
 # Once we've set up the system path, run the spack main method
 if __name__ == "__main__":
-    sys.exit(main())
+    sys.exit(spack.main.main())

bin/spack-tmpconfig

@@ -1,95 +0,0 @@
-#!/bin/bash
-set -euo pipefail
-[[ -n "${TMPCONFIG_DEBUG:=}" ]] && set -x
-DIR="$(cd -P "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-mkdir -p "${XDG_RUNTIME_DIR:=/tmp}/spack-tests"
-export TMPDIR="${XDG_RUNTIME_DIR}"
-export TMP_DIR="$(mktemp -d -t spack-test-XXXXX)"
-clean_up() {
-    [[ -n "$TMPCONFIG_DEBUG" ]] && printf "cleaning up: $TMP_DIR\n"
-    rm -rf "$TMP_DIR"
-}
-trap clean_up EXIT
-trap clean_up ERR
-
-[[ -n "$TMPCONFIG_DEBUG" ]] && printf "Redirecting TMP_DIR and spack directories to $TMP_DIR\n"
-
-export BOOTSTRAP="${SPACK_USER_CACHE_PATH:=$HOME/.spack}/bootstrap"
-export SPACK_USER_CACHE_PATH="$TMP_DIR/user_cache"
-mkdir -p "$SPACK_USER_CACHE_PATH"
-
-private_bootstrap="$SPACK_USER_CACHE_PATH/bootstrap"
-use_spack=''
-use_bwrap=''
-# argument handling
-while (($# >= 1)) ; do
-    case "$1" in
-        -b) # privatize bootstrap too, useful for CI but not always cheap
-            shift
-            export BOOTSTRAP="$private_bootstrap"
-            ;;
-        -B) # use specified bootstrap dir
-            export BOOTSTRAP="$2"
-            shift 2
-            ;;
-        -s) # run spack directly with remaining args
-            shift
-            use_spack=1
-            ;;
-        --contain=bwrap)
-            if bwrap --help 2>&1 > /dev/null ; then
-                use_bwrap=1
-            else
-                echo Bubblewrap containment requested, but no bwrap command found
-                exit 1
-            fi
-            shift
-            ;;
-        --)
-            shift
-            break
-            ;;
-        *)
-            break
-            ;;
-    esac
-done
-typeset -a CMD
-if [[ -n "$use_spack" ]] ; then
-    CMD=("$DIR/spack" "$@")
-else
-    CMD=("$@")
-fi
-
-mkdir -p "$BOOTSTRAP"
-
-export SPACK_SYSTEM_CONFIG_PATH="$TMP_DIR/sys_conf"
-export SPACK_USER_CONFIG_PATH="$TMP_DIR/user_conf"
-mkdir -p "$SPACK_USER_CONFIG_PATH"
-cat >"$SPACK_USER_CONFIG_PATH/config.yaml" <<EOF
-config:
-  install_tree:
-    root: $TMP_DIR/install
-  misc_cache: $$user_cache_path/cache
-  source_cache: $$user_cache_path/source
-EOF
-cat >"$SPACK_USER_CONFIG_PATH/bootstrap.yaml" <<EOF
-bootstrap:
-  root: $BOOTSTRAP
-EOF
-
-if [[ -n "$use_bwrap" ]] ; then
-    CMD=(
-        bwrap
-        --dev-bind / /
-        --ro-bind "$DIR/.." "$DIR/.." # do not touch spack root
-        --ro-bind $HOME/.spack $HOME/.spack # do not touch user config/cache dir
-        --bind "$TMP_DIR" "$TMP_DIR"
-        --bind "$BOOTSTRAP" "$BOOTSTRAP"
-        --die-with-parent
-        "${CMD[@]}"
-    )
-fi
-
-(( ${TMPCONFIG_DEBUG:=0} > 1)) && echo "Running: ${CMD[@]}"
-"${CMD[@]}"

etc/spack/defaults/bootstrap.yaml

@@ -9,15 +9,14 @@ bootstrap:
   # may not be able to bootstrap all the software that Spack needs,
   # depending on its type.
   sources:
-  - name: 'github-actions-v0.4'
-    metadata: $spack/share/spack/bootstrap/github-actions-v0.4
-  - name: 'github-actions-v0.3'
-    metadata: $spack/share/spack/bootstrap/github-actions-v0.3
+  - name: 'github-actions-v0.2'
+    metadata: $spack/share/spack/bootstrap/github-actions-v0.2
+  - name: 'github-actions-v0.1'
+    metadata: $spack/share/spack/bootstrap/github-actions-v0.1
   - name: 'spack-install'
     metadata: $spack/share/spack/bootstrap/spack-install
   trusted:
     # By default we trust bootstrapping from sources and from binaries
     # produced on Github via the workflow
-    github-actions-v0.4: true
-    github-actions-v0.3: true
+    github-actions-v0.2: true
     spack-install: true

etc/spack/defaults/concretizer.yaml

@@ -33,4 +33,4 @@ concretizer:
   # environments can always be activated. When "false" perform concretization separately
   # on each root spec, allowing different versions and variants of the same package in
   # an environment.
-  unify: true
+  unify: false

etc/spack/defaults/config.yaml

@@ -19,7 +19,7 @@ config:
   install_tree:
     root: $spack/opt/spack
     projections:
-      all: "{architecture}/{compiler.name}-{compiler.version}/{name}-{version}-{hash}"
+      all: "${ARCHITECTURE}/${COMPILERNAME}-${COMPILERVER}/${PACKAGE}-${VERSION}-${HASH}"
     # install_tree can include an optional padded length (int or boolean)
     # default is False (do not pad)
     # if padded_length is True, Spack will pad as close to the system max path
@@ -187,20 +187,10 @@ config:
   package_lock_timeout: null
 
 
-  # Control how shared libraries are located at runtime on Linux. See the
-  # the Spack documentation for details.
-  shared_linking:
-    # Spack automatically embeds runtime search paths in ELF binaries for their
-    # dependencies. Their type can either be "rpath" or "runpath". For glibc, rpath is
-    # inherited and has precedence over LD_LIBRARY_PATH; runpath is not inherited
-    # and of lower precedence. DO NOT MIX these within the same install tree.
-    type: rpath
-
-
-    # (Experimental) Embed absolute paths of dependent libraries directly in ELF
-    # binaries to avoid runtime search. This can improve startup time of
-    # executables with many dependencies, in particular on slow filesystems.
-    bind: false
+  # Control whether Spack embeds RPATH or RUNPATH attributes in ELF binaries.
+  # Has no effect on macOS. DO NOT MIX these within the same install tree.
+  # See the Spack documentation for details.
+  shared_linking: 'rpath'
 
 
   # Set to 'false' to allow installation on filesystems that doesn't allow setgid bit
@@ -211,11 +201,3 @@ config:
   # building and installing packages. This gives information about Spack's
   # current progress as well as the current and total number of packages.
   terminal_title: false
-
-  # Number of seconds a buildcache's index.json is cached locally before probing
-  # for updates, within a single Spack invocation. Defaults to 10 minutes.
-  binary_index_ttl: 600
-
-  flags:
-    # Whether to keep -Werror flags active in package builds.
-    keep_werror: 'none'

etc/spack/defaults/cray/modules.yaml

@@ -13,4 +13,9 @@
 # Per-user settings (overrides default and site settings):
 #   ~/.spack/modules.yaml
 # -------------------------------------------------------------------------
-modules: {}
+modules:
+  prefix_inspections:
+    lib:
+      - LD_LIBRARY_PATH
+    lib64:
+      - LD_LIBRARY_PATH

etc/spack/defaults/darwin/modules.yaml

@@ -15,7 +15,7 @@
 # -------------------------------------------------------------------------
 modules:
   prefix_inspections:
-    ./lib:
+    lib:
       - DYLD_FALLBACK_LIBRARY_PATH
-    ./lib64:
+    lib64:
       - DYLD_FALLBACK_LIBRARY_PATH

etc/spack/defaults/linux/modules.yaml

@@ -13,4 +13,9 @@
 # Per-user settings (overrides default and site settings):
 #   ~/.spack/modules.yaml
 # -------------------------------------------------------------------------
-modules: {}
+modules:
+  prefix_inspections:
+    lib:
+      - LD_LIBRARY_PATH
+    lib64:
+      - LD_LIBRARY_PATH

etc/spack/defaults/modules.yaml

@@ -14,24 +14,23 @@
 #   ~/.spack/modules.yaml
 # -------------------------------------------------------------------------
 modules:
-  # This maps paths in the package install prefix to environment variables
-  # they should be added to. For example, <prefix>/bin should be in PATH.
+  # Paths to check when creating modules for all module sets
   prefix_inspections:
-    ./bin:
+    bin:
       - PATH
-    ./man:
+    man:
       - MANPATH
-    ./share/man:
+    share/man:
       - MANPATH
-    ./share/aclocal:
+    share/aclocal:
       - ACLOCAL_PATH
-    ./lib/pkgconfig:
+    lib/pkgconfig:
       - PKG_CONFIG_PATH
-    ./lib64/pkgconfig:
+    lib64/pkgconfig:
       - PKG_CONFIG_PATH
-    ./share/pkgconfig:
+    share/pkgconfig:
       - PKG_CONFIG_PATH
-    ./:
+    '':
       - CMAKE_PREFIX_PATH
 
   # These are configurations for the module set named "default"

etc/spack/defaults/packages.yaml

@@ -25,18 +25,16 @@ packages:
       fftw-api: [fftw, amdfftw]
       flame: [libflame, amdlibflame]
       fuse: [libfuse]
-      gl: [glx, osmesa]
+      gl: [mesa+opengl, mesa18, opengl]
       glu: [mesa-glu, openglu]
-      golang: [go, gcc]
-      go-external-or-gccgo-bootstrap: [go-bootstrap, gcc]
+      glx: [mesa+glx, mesa18+glx, opengl]
+      golang: [gcc]
       iconv: [libiconv]
       ipp: [intel-ipp]
       java: [openjdk, jdk, ibm-java]
       jpeg: [libjpeg-turbo, libjpeg]
       lapack: [openblas, amdlibflame]
-      libglx: [mesa+glx, mesa18+glx]
-      libllvm: [llvm]
-      libosmesa: [mesa+osmesa, mesa18+osmesa]
+      libllvm: [llvm, llvm-amdgpu]
       lua-lang: [lua, lua-luajit-openresty, lua-luajit]
       luajit: [lua-luajit-openresty, lua-luajit]
       mariadb-client: [mariadb-c-client, mariadb]
@@ -46,6 +44,7 @@ packages:
       mysql-client: [mysql, mariadb-c-client]
       opencl: [pocl]
       onedal: [intel-oneapi-dal]
+      osmesa: [mesa+osmesa, mesa18+osmesa]
       pbs: [openpbs, torque]
       pil: [py-pillow]
       pkgconfig: [pkgconf, pkg-config]

etc/spack/defaults/windows/config.yaml

@@ -1,5 +1,5 @@
 config:
   locks: false
-  concretizer: clingo
+  concretizer: original
   build_stage::
     - '$spack/.staging'

lib/spack/docs/_spack_root

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

lib/spack/docs/basic_usage.rst

@@ -85,7 +85,7 @@ All packages whose names or descriptions contain documentation:
 To get more information on a particular package from `spack list`, use
 `spack info`.  Just supply the name of a package:
 
-.. command-output:: spack info --all mpich
+.. command-output:: spack info mpich
 
 Most of the information is self-explanatory.  The *safe versions* are
 versions that Spack knows the checksum for, and it will use the
@@ -896,8 +896,8 @@ your path:
    $ which mpicc
    ~/spack/opt/linux-debian7-x86_64/gcc@4.4.7/mpich@3.0.4/bin/mpicc
 
-These commands will add appropriate directories to your ``PATH``
-and ``MANPATH`` according to the
+These commands will add appropriate directories to your ``PATH``,
+``MANPATH``, ``CPATH``, and ``LD_LIBRARY_PATH`` according to the
 :ref:`prefix inspections <customize-env-modifications>` defined in your
 modules configuration.
 When you no longer want to use a package, you can type unload or
@@ -998,15 +998,11 @@ More formally, a spec consists of the following pieces:
 * ``%`` Optional compiler specifier, with an optional compiler version
   (``gcc`` or ``gcc@4.7.3``)
 * ``+`` or ``-`` or ``~`` Optional variant specifiers (``+debug``,
-  ``-qt``, or ``~qt``) for boolean variants. Use ``++`` or ``--`` or
-  ``~~`` to propagate variants through the dependencies (``++debug``,
-  ``--qt``, or ``~~qt``).
+  ``-qt``, or ``~qt``) for boolean variants
 * ``name=<value>`` Optional variant specifiers that are not restricted to
-  boolean variants. Use ``name==<value>`` to propagate variant through the
-  dependencies.
+  boolean variants
 * ``name=<value>`` Optional compiler flag specifiers. Valid flag names are
   ``cflags``, ``cxxflags``, ``fflags``, ``cppflags``, ``ldflags``, and ``ldlibs``.
-  Use ``name==<value>`` to propagate compiler flags through the dependencies.
 * ``target=<value> os=<value>`` Optional architecture specifier
   (``target=haswell os=CNL10``)
 * ``^`` Dependency specs (``^callpath@1.1``)
@@ -1097,8 +1093,6 @@ could depend on ``mpich@1.2:`` if it can only build with version
 
 Below are more details about the specifiers that you can add to specs.
 
-.. _version-specifier:
-
 ^^^^^^^^^^^^^^^^^
 Version specifier
 ^^^^^^^^^^^^^^^^^
@@ -1114,37 +1108,6 @@ set of arbitrary versions, such as ``@1.0,1.5,1.7`` (``1.0``, ``1.5``,
 or ``1.7``).  When you supply such a specifier to ``spack install``,
 it constrains the set of versions that Spack will install.
 
-For packages with a ``git`` attribute, ``git`` references
-may be specified instead of a numerical version i.e. branches, tags
-and commits. Spack will stage and build based off the ``git``
-reference provided.  Acceptable syntaxes for this are:
-
-.. code-block:: sh
-
-    # branches and tags
-   foo@git.develop # use the develop branch
-   foo@git.0.19 # use the 0.19 tag
-
-    # commit hashes
-   foo@abcdef1234abcdef1234abcdef1234abcdef1234    # 40 character hashes are automatically treated as git commits
-   foo@git.abcdef1234abcdef1234abcdef1234abcdef1234
-
-Spack versions from git reference either have an associated version supplied by the user,
-or infer a relationship to known versions from the structure of the git repository. If an
-associated version is supplied by the user, Spack treats the git version as equivalent to that
-version for all version comparisons in the package logic (e.g. ``depends_on('foo', when='@1.5')``).
-
-The associated version can be assigned with ``[git ref]=[version]`` syntax, with the caveat that the specified version is known to Spack from either the package definition, or in the configuration preferences (i.e. ``packages.yaml``).
-
-.. code-block:: sh
-
-   foo@git.my_ref=3.2 # use the my_ref tag or branch, but treat it as version 3.2 for version comparisons
-   foo@git.abcdef1234abcdef1234abcdef1234abcdef1234=develop # use the given commit, but treat it as develop for version comparisons
-
-If an associated version is not supplied then the tags in the git repo are used to determine
-the most recent previous version known to Spack. Details about how versions are compared
-and how Spack determines if one version is less than another are discussed in the developer guide.
-
 If the version spec is not provided, then Spack will choose one
 according to policies set for the particular spack installation.  If
 the spec is ambiguous, i.e. it could match multiple versions, Spack
@@ -1230,23 +1193,6 @@ variants using the backwards compatibility syntax and uses only ``~``
 for disabled boolean variants.  The ``-`` and spaces on the command
 line are provided for convenience and legibility.
 
-Spack allows variants to propagate their value to the package's
-dependency by using ``++``, ``--``, and ``~~`` for boolean variants.
-For example, for a ``debug`` variant:
-
-.. code-block:: sh
-
-    mpileaks ++debug   # enabled debug will be propagated to dependencies
-    mpileaks +debug    # only mpileaks will have debug enabled
-
-To propagate the value of non-boolean variants Spack uses ``name==value``.
-For example, for the ``stackstart`` variant:
-
-.. code-block:: sh
-
-    mpileaks stackstart==4   # variant will be propagated to dependencies
-    mpileaks stackstart=4    # only mpileaks will have this variant value
-
 ^^^^^^^^^^^^^^
 Compiler Flags
 ^^^^^^^^^^^^^^
@@ -1254,15 +1200,10 @@ Compiler Flags
 Compiler flags are specified using the same syntax as non-boolean variants,
 but fulfill a different purpose. While the function of a variant is set by
 the package, compiler flags are used by the compiler wrappers to inject
-flags into the compile line of the build. Additionally, compiler flags can
-be inherited by dependencies by using ``==``.
-``spack install libdwarf cppflags=="-g"`` will install both libdwarf and
-libelf with the ``-g`` flag injected into their compile line.
-
-.. note::
-
-   versions of spack prior to 0.19.0 will propagate compiler flags using
-   the ``=`` syntax.
+flags into the compile line of the build. Additionally, compiler flags are
+inherited by dependencies. ``spack install libdwarf cppflags="-g"`` will
+install both libdwarf and libelf with the ``-g`` flag injected into their
+compile line.
 
 Notice that the value of the compiler flags must be quoted if it
 contains any spaces. Any of ``cppflags=-O3``, ``cppflags="-O3"``,
@@ -1464,7 +1405,7 @@ built.
 You can see what virtual packages a particular package provides by
 getting info on it:
 
-.. command-output:: spack info --virtuals mpich
+.. command-output:: spack info mpich
 
 Spack is unique in that its virtual packages can be versioned, just
 like regular packages.  A particular version of a package may provide
@@ -1672,13 +1613,9 @@ own install prefix.  However, certain packages are typically installed
 `Python <https://www.python.org>`_ packages are typically installed in the
 ``$prefix/lib/python-2.7/site-packages`` directory.
 
-In Spack, installation prefixes are immutable, so this type of installation
-is not directly supported. However, it is possible to create views that
-allow you to merge install prefixes of multiple packages into a single new prefix.
-Views are a convenient way to get a more traditional filesystem structure.
-Using *extensions*, you can ensure that Python packages always share the
-same prefix in the view as Python itself. Suppose you have
-Python installed like so:
+Spack has support for this type of installation as well.  In Spack,
+a package that can live inside the prefix of another package is called
+an *extension*.  Suppose you have Python installed like so:
 
 .. code-block:: console
 
@@ -1716,6 +1653,8 @@ You can find extensions for your Python installation like this:
    py-ipython@2.3.1     py-pygments@2.0.1   py-setuptools@11.3.1
    py-matplotlib@1.4.2  py-pyparsing@2.0.3  py-six@1.9.0
 
+   ==> None activated.
+
 The extensions are a subset of what's returned by ``spack list``, and
 they are packages like any other.  They are installed into their own
 prefixes, and you can see this with ``spack find --paths``:
@@ -1743,72 +1682,32 @@ directly when you run ``python``:
    ImportError: No module named numpy
    >>>
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Using Extensions in Environments
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^^
+Using Extensions
+^^^^^^^^^^^^^^^^
 
-The recommended way of working with extensions such as ``py-numpy``
-above is through :ref:`Environments <environments>`. For example,
-the following creates an environment in the current working directory
-with a filesystem view in the ``./view`` directory:
-
-.. code-block:: console
-
-   $ spack env create --with-view view --dir .
-   $ spack -e . add py-numpy
-   $ spack -e . concretize
-   $ spack -e . install
-
-We recommend environments for two reasons. Firstly, environments
-can be activated (requires :ref:`shell-support`):
-
-.. code-block:: console
-
-   $ spack env activate .
-
-which sets all the right environment variables such as ``PATH`` and
-``PYTHONPATH``. This ensures that
-
-.. code-block:: console
-
-   $ python
-   >>> import numpy
-
-works. Secondly, even without shell support, the view ensures
-that Python can locate its extensions:
-
-.. code-block:: console
-
-   $ ./view/bin/python
-   >>> import numpy
-
-See :ref:`environments` for a more in-depth description of Spack
-environments and customizations to views.
-
-^^^^^^^^^^^^^^^^^^^^
-Using ``spack load``
-^^^^^^^^^^^^^^^^^^^^
-
-A more traditional way of using Spack and extensions is ``spack load``
-(requires :ref:`shell-support`). This will add the extension to ``PYTHONPATH``
-in your current shell, and Python itself will be available in the ``PATH``:
+There are four ways to get ``numpy`` working in Python.  The first is
+to use :ref:`shell-support`.  You can simply ``load`` the extension,
+and it will be added to the ``PYTHONPATH`` in your current shell:
 
 .. code-block:: console
 
+   $ spack load python
    $ spack load py-numpy
-   $ python
-   >>> import numpy
 
+Now ``import numpy`` will succeed for as long as you keep your current
+session open.
 The loaded packages can be checked using ``spack find --loaded``
 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Loading Extensions via Modules
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-Apart from ``spack env activate`` and ``spack load``, you can load numpy
-through your environment modules (using ``environment-modules`` or
-``lmod``). This will also add the extension to the ``PYTHONPATH`` in
-your current shell.
+Instead of using Spack's environment modification capabilities through
+the ``spack load`` command, you can load numpy through your
+environment modules (using ``environment-modules`` or ``lmod``). This
+will also add the extension to the ``PYTHONPATH`` in your current
+shell.
 
 .. code-block:: console
 
@@ -1818,6 +1717,130 @@ If you do not know the name of the specific numpy module you wish to
 load, you can use the ``spack module tcl|lmod loads`` command to get
 the name of the module from the Spack spec.
 
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Activating Extensions in a View
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Another way to use extensions is to create a view, which merges the
+python installation along with the extensions into a single prefix.
+See :ref:`configuring_environment_views` for a more in-depth description
+of views.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Activating Extensions Globally
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+As an alternative to creating a merged prefix with Python and its extensions,
+and prior to support for views, Spack has provided a means to install the
+extension into the Spack installation prefix for the extendee. This has
+typically been useful since extendable packages typically search their own
+installation path for addons by default.
+
+Global activations are performed with the ``spack activate`` command:
+
+.. _cmd-spack-activate:
+
+^^^^^^^^^^^^^^^^^^
+``spack activate``
+^^^^^^^^^^^^^^^^^^
+
+.. code-block:: console
+
+   $ spack activate py-numpy
+   ==> Activated extension py-setuptools@11.3.1%gcc@4.4.7 arch=linux-debian7-x86_64-3c74eb69 for python@2.7.8%gcc@4.4.7.
+   ==> Activated extension py-nose@1.3.4%gcc@4.4.7 arch=linux-debian7-x86_64-5f70f816 for python@2.7.8%gcc@4.4.7.
+   ==> Activated extension py-numpy@1.9.1%gcc@4.4.7 arch=linux-debian7-x86_64-66733244 for python@2.7.8%gcc@4.4.7.
+
+Several things have happened here.  The user requested that
+``py-numpy`` be activated in the ``python`` installation it was built
+with.  Spack knows that ``py-numpy`` depends on ``py-nose`` and
+``py-setuptools``, so it activated those packages first.  Finally,
+once all dependencies were activated in the ``python`` installation,
+``py-numpy`` was activated as well.
+
+If we run ``spack extensions`` again, we now see the three new
+packages listed as activated:
+
+.. code-block:: console
+
+   $ spack extensions python
+   ==> python@2.7.8%gcc@4.4.7  arch=linux-debian7-x86_64-703c7a96
+   ==> 36 extensions:
+   geos          py-ipython     py-pexpect    py-pyside            py-sip
+   py-basemap    py-libxml2     py-pil        py-pytz              py-six
+   py-biopython  py-mako        py-pmw        py-rpy2              py-sympy
+   py-cython     py-matplotlib  py-pychecker  py-scientificpython  py-virtualenv
+   py-dateutil   py-mpi4py      py-pygments   py-scikit-learn
+   py-epydoc     py-mx          py-pylint     py-scipy
+   py-gnuplot    py-nose        py-pyparsing  py-setuptools
+   py-h5py       py-numpy       py-pyqt       py-shiboken
+
+   ==> 12 installed:
+   -- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
+   py-dateutil@2.4.0    py-nose@1.3.4       py-pyside@1.2.2
+   py-dateutil@2.4.0    py-numpy@1.9.1      py-pytz@2014.10
+   py-ipython@2.3.1     py-pygments@2.0.1   py-setuptools@11.3.1
+   py-matplotlib@1.4.2  py-pyparsing@2.0.3  py-six@1.9.0
+
+   ==> 3 currently activated:
+   -- linux-debian7-x86_64 / gcc@4.4.7 --------------------------------
+   py-nose@1.3.4  py-numpy@1.9.1  py-setuptools@11.3.1
+
+Now, when a user runs python, ``numpy`` will be available for import
+*without* the user having to explicitly load it.  ``python@2.7.8`` now
+acts like a system Python installation with ``numpy`` installed inside
+of it.
+
+Spack accomplishes this by symbolically linking the *entire* prefix of
+the ``py-numpy`` package into the prefix of the ``python`` package.  To the
+python interpreter, it looks like ``numpy`` is installed in the
+``site-packages`` directory.
+
+The only limitation of global activation is that you can only have a *single*
+version of an extension activated at a time.  This is because multiple
+versions of the same extension would conflict if symbolically linked
+into the same prefix.  Users who want a different version of a package
+can still get it by using environment modules or views, but they will have to
+explicitly load their preferred version.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+``spack activate --force``
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If, for some reason, you want to activate a package *without* its
+dependencies, you can use ``spack activate --force``:
+
+.. code-block:: console
+
+   $ spack activate --force py-numpy
+   ==> Activated extension py-numpy@1.9.1%gcc@4.4.7 arch=linux-debian7-x86_64-66733244 for python@2.7.8%gcc@4.4.7.
+
+.. _cmd-spack-deactivate:
+
+^^^^^^^^^^^^^^^^^^^^
+``spack deactivate``
+^^^^^^^^^^^^^^^^^^^^
+
+We've seen how activating an extension can be used to set up a default
+version of a Python module.  Obviously, you may want to change that at
+some point.  ``spack deactivate`` is the command for this.  There are
+several variants:
+
+* ``spack deactivate <extension>`` will deactivate a single
+  extension.  If another activated extension depends on this one,
+  Spack will warn you and exit with an error.
+* ``spack deactivate --force <extension>`` deactivates an extension
+  regardless of packages that depend on it.
+* ``spack deactivate --all <extension>`` deactivates an extension and
+  all of its dependencies.  Use ``--force`` to disregard dependents.
+* ``spack deactivate --all <extendee>`` deactivates *all* activated
+  extensions of a package.  For example, to deactivate *all* python
+  extensions, use:
+
+  .. code-block:: console
+
+     $ spack deactivate --all python
+
 -----------------------
 Filesystem requirements
 -----------------------

lib/spack/docs/bootstrapping.rst

@@ -15,13 +15,15 @@ is an entire command dedicated to the management of every aspect of bootstrappin
 
 .. command-output:: spack bootstrap --help
 
-Spack is configured to bootstrap its dependencies lazily by default; i.e. the first time they are needed and
-can't be found. You can readily check if any prerequisite for using Spack is missing by running:
+The first thing to know to understand bootstrapping in Spack is that each of
+Spack's dependencies is bootstrapped lazily; i.e. the first time it is needed and
+can't be found. You can readily check if any prerequisite for using Spack
+is missing by running:
 
 .. code-block:: console
 
    % spack bootstrap status
-   Spack v0.19.0 - python@3.8
+   Spack v0.17.1 - python@3.8
 
    [FAIL] Core Functionalities
      [B] MISSING "clingo": required to concretize specs
@@ -46,21 +48,6 @@ they can be bootstrapped. Running a command that concretize a spec, like:
 
 triggers the bootstrapping of clingo from pre-built binaries as expected.
 
-Users can also bootstrap all the dependencies needed by Spack in a single command, which
-might be useful to setup containers or other similar environments:
-
-.. code-block:: console
-
-   $ spack bootstrap now
-   ==> Bootstrapping clingo from pre-built binaries
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.3/build_cache/linux-centos7-x86_64-gcc-10.2.1-clingo-bootstrap-spack-shqedxgvjnhiwdcdrvjhbd73jaevv7wt.spec.json
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.3/build_cache/linux-centos7-x86_64/gcc-10.2.1/clingo-bootstrap-spack/linux-centos7-x86_64-gcc-10.2.1-clingo-bootstrap-spack-shqedxgvjnhiwdcdrvjhbd73jaevv7wt.spack
-   ==> Installing "clingo-bootstrap@spack%gcc@10.2.1~docs~ipo+python+static_libstdcpp build_type=Release arch=linux-centos7-x86_64" from a buildcache
-   ==> Bootstrapping patchelf from pre-built binaries
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.3/build_cache/linux-centos7-x86_64-gcc-10.2.1-patchelf-0.15.0-htk62k7efo2z22kh6kmhaselru7bfkuc.spec.json
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.3/build_cache/linux-centos7-x86_64/gcc-10.2.1/patchelf-0.15.0/linux-centos7-x86_64-gcc-10.2.1-patchelf-0.15.0-htk62k7efo2z22kh6kmhaselru7bfkuc.spack
-   ==> Installing "patchelf@0.15.0%gcc@10.2.1 ldflags="-static-libstdc++ -static-libgcc"  arch=linux-centos7-x86_64" from a buildcache
-
 -----------------------
 The Bootstrapping store
 -----------------------
@@ -120,19 +107,19 @@ If need be, you can disable bootstrapping altogether by running:
 
 in which case it's your responsibility to ensure Spack runs in an
 environment where all its prerequisites are installed. You can
-also configure Spack to skip certain bootstrapping methods by disabling
-them specifically:
+also configure Spack to skip certain bootstrapping methods by *untrusting*
+them. For instance:
 
 .. code-block:: console
 
-   % spack bootstrap disable github-actions
-   ==> "github-actions" is now disabled and will not be used for bootstrapping
+   % spack bootstrap untrust github-actions
+   ==> "github-actions" is now untrusted and will not be used for bootstrapping
 
 tells Spack to skip trying to bootstrap from binaries. To add the "github-actions" method back you can:
 
 .. code-block:: console
 
-   % spack bootstrap enable github-actions
+   % spack bootstrap trust github-actions
 
 There is also an option to reset the bootstrapping configuration to Spack's defaults:
 

lib/spack/docs/build_settings.rst

@@ -49,8 +49,9 @@ packages rather than building its own packages. This may be desirable
 if machines ship with system packages, such as a customized MPI
 that should be used instead of Spack building its own MPI.
 
-External packages are configured through the ``packages.yaml`` file.
-Here's an example of an external configuration:
+External packages are configured through the ``packages.yaml`` file found
+in a Spack installation's ``etc/spack/`` or a user's ``~/.spack/``
+directory. Here's an example of an external configuration:
 
 .. code-block:: yaml
 
@@ -96,14 +97,11 @@ Each package version and compiler listed in an external should
 have entries in Spack's packages and compiler configuration, even
 though the package and compiler may not ever be built.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Prevent packages from being built from sources
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-Adding an external spec in ``packages.yaml`` allows Spack to use an external location,
-but it does not prevent Spack from building packages from sources. In the above example,
-Spack might choose for many valid reasons to start building and linking with the
-latest version of OpenMPI rather than continue using the pre-installed OpenMPI versions.
+The packages configuration can tell Spack to use an external location
+for certain package versions, but it does not restrict Spack to using
+external packages.  In the above example, since newer versions of OpenMPI
+are available, Spack will choose to start building and linking with the
+latest version rather than continue using the pre-installed OpenMPI versions.
 
 To prevent this, the ``packages.yaml`` configuration also allows packages
 to be flagged as non-buildable.  The previous example could be modified to
@@ -123,15 +121,9 @@ be:
        buildable: False
 
 The addition of the ``buildable`` flag tells Spack that it should never build
-its own version of OpenMPI from sources, and it will instead always rely on a pre-built
-OpenMPI.
-
-.. note::
-
-   If ``concretizer:reuse`` is on (see :ref:`concretizer-options` for more information on that flag)
-   pre-built specs include specs already available from a local store, an upstream store, a registered
-   buildcache or specs marked as externals in ``packages.yaml``. If ``concretizer:reuse`` is off, only
-   external specs in ``packages.yaml`` are included in the list of pre-built specs.
+its own version of OpenMPI, and it will instead always rely on a pre-built
+OpenMPI.  Similar to ``paths``, ``buildable`` is specified as a property under
+a package name.
 
 If an external module is specified as not buildable, then Spack will load the
 external module into the build environment which can be used for linking.
@@ -140,10 +132,6 @@ The ``buildable`` does not need to be paired with external packages.
 It could also be used alone to forbid packages that may be
 buggy or otherwise undesirable.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Non-buildable virtual packages
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 Virtual packages in Spack can also be specified as not buildable, and
 external implementations can be provided. In the example above,
 OpenMPI is configured as not buildable, but Spack will often prefer
@@ -165,37 +153,21 @@ but more conveniently:
        - spec: "openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64"
          prefix: /opt/openmpi-1.6.5-intel
 
-Spack can then use any of the listed external implementations of MPI
-to satisfy a dependency, and will choose depending on the compiler and
-architecture.
-
-In cases where the concretizer is configured to reuse specs, and other ``mpi`` providers
-(available via stores or buildcaches) are not wanted, Spack can be configured to require
-specs matching only the available externals:
+Implementations can also be listed immediately under the virtual they provide:
 
 .. code-block:: yaml
 
    packages:
      mpi:
        buildable: False
-       require:
-       - one_of: [
-           "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64",
-           "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug",
-           "openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64"
-         ]
-     openmpi:
-       externals:
-       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64"
-         prefix: /opt/openmpi-1.4.3
-       - spec: "openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug"
-         prefix: /opt/openmpi-1.4.3-debug
-       - spec: "openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64"
-         prefix: /opt/openmpi-1.6.5-intel
+         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64: /opt/openmpi-1.4.3
+         openmpi@1.4.3%gcc@4.4.7 arch=linux-debian7-x86_64+debug: /opt/openmpi-1.4.3-debug
+         openmpi@1.6.5%intel@10.1 arch=linux-debian7-x86_64: /opt/openmpi-1.6.5-intel
+         mpich@3.3 %clang@9.0.0 arch=linux-debian7-x86_64: /opt/mpich-3.3-intel
 
-This configuration prevents any spec using MPI and originating from stores or buildcaches to be reused,
-unless it matches the requirements under ``packages:mpi:require``. For more information on requirements see
-:ref:`package-requirements`.
+Spack can then use any of the listed external implementations of MPI
+to satisfy a dependency, and will choose depending on the compiler and
+architecture.
 
 .. _cmd-spack-external-find:
 
@@ -222,6 +194,11 @@ Specific limitations include:
 * Packages are not discoverable by default: For a package to be
   discoverable with ``spack external find``, it needs to add special
   logic. See :ref:`here <make-package-findable>` for more details.
+* The current implementation only collects and examines executable files,
+  so it is typically only useful for build/run dependencies (in some cases
+  if a library package also provides an executable, it may be possible to
+  extract a meaningful Spec by running the executable - for example the
+  compiler wrappers in MPI implementations).
 * The logic does not search through module files, it can only detect
   packages with executables defined in ``PATH``; you can help Spack locate
   externals which use module files by loading any associated modules for
@@ -302,143 +279,17 @@ microarchitectures considered during the solve are constrained to be compatible
 host Spack is currently running on. For instance, if this option is set to ``true``, a
 user cannot concretize for ``target=icelake`` while running on an Haswell node.
 
-.. _package-requirements:
-
---------------------
-Package Requirements
---------------------
-
-Spack can be configured to always use certain compilers, package
-versions, and variants during concretization through package
-requirements.
-
-Package requirements are useful when you find yourself repeatedly
-specifying the same constraints on the command line, and wish that
-Spack respects these constraints whether you mention them explicitly
-or not. Another use case is specifying constraints that should apply
-to all root specs in an environment, without having to repeat the
-constraint everywhere.
-
-Apart from that, requirements config is more flexible than constraints
-on the command line, because it can specify constraints on packages
-*when they occur* as a dependency. In contrast, on the command line it
-is not possible to specify constraints on dependencies while also keeping
-those dependencies optional.
-
-The package requirements configuration is specified in ``packages.yaml``
-keyed by package name:
-
-.. code-block:: yaml
-
-   packages:
-     libfabric:
-       require: "@1.13.2"
-     openmpi:
-       require:
-       - any_of: ["~cuda", "%gcc"]
-     mpich:
-      require:
-      - one_of: ["+cuda", "+rocm"]
-
-Requirements are expressed using Spec syntax (the same as what is provided
-to ``spack install``). In the simplest case, you can specify attributes
-that you always want the package to have by providing a single spec to
-``require``; in the above example, ``libfabric`` will always build
-with version 1.13.2.
-
-You can provide a more-relaxed constraint and allow the concretizer to
-choose between a set of options using ``any_of`` or ``one_of``:
-
-* ``any_of`` is a list of specs. One of those specs must be satisfied
-  and it is also allowed for the concretized spec to match more than one.
-  In the above example, that means you could build ``openmpi+cuda%gcc``,
-  ``openmpi~cuda%clang`` or ``openmpi~cuda%gcc`` (in the last case,
-  note that both specs in the ``any_of`` for ``openmpi`` are
-  satisfied).
-* ``one_of`` is also a list of specs, and the final concretized spec
-  must match exactly one of them.  In the above example, that means
-  you could build ``mpich+cuda`` or ``mpich+rocm`` but not
-  ``mpich+cuda+rocm`` (note the current package definition for
-  ``mpich`` already includes a conflict, so this is redundant but
-  still demonstrates the concept).
-
-.. note::
-
-   For ``any_of`` and ``one_of``, the order of specs indicates a
-   preference: items that appear earlier in the list are preferred
-   (note that these preferences can be ignored in favor of others).
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Setting default requirements
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-You can also set default requirements for all packages under ``all``
-like this:
-
-.. code-block:: yaml
-
-   packages:
-     all:
-       require: '%clang'
-
-which means every spec will be required to use ``clang`` as a compiler.
-
-Note that in this case ``all`` represents a *default set of requirements* -
-if there are specific package requirements, then the default requirements
-under ``all`` are disregarded. For example, with a configuration like this:
-
-.. code-block:: yaml
-
-   packages:
-     all:
-       require: '%clang'
-     cmake:
-       require: '%gcc'
-
-Spack requires ``cmake`` to use ``gcc`` and all other nodes (including ``cmake``
-dependencies) to use ``clang``.
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Setting requirements on virtual specs
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-A requirement on a virtual spec applies whenever that virtual is present in the DAG.
-This can be useful for fixing which virtual provider you want to use:
-
-.. code-block:: yaml
-
-   packages:
-     mpi:
-       require: 'mvapich2 %gcc'
-
-With the configuration above the only allowed ``mpi`` provider is ``mvapich2 %gcc``.
-
-Requirements on the virtual spec and on the specific provider are both applied, if
-present. For instance with a configuration like:
-
-.. code-block:: yaml
-
-   packages:
-     mpi:
-       require: 'mvapich2 %gcc'
-     mvapich2:
-       require: '~cuda'
-
-you will use ``mvapich2~cuda %gcc`` as an ``mpi`` provider.
-
 .. _package-preferences:
 
 -------------------
 Package Preferences
 -------------------
 
-In some cases package requirements can be too strong, and package
-preferences are the better option. Package preferences do not impose
-constraints on packages for particular versions or variants values,
-they rather only set defaults -- the concretizer is free to change
-them if it must due to other constraints. Also note that package
-preferences are of lower priority than reuse of already installed
-packages.
+Spack can be configured to prefer certain compilers, package
+versions, dependencies, and variants during concretization.
+The preferred configuration can be controlled via the
+``~/.spack/packages.yaml`` file for user configurations, or the
+``etc/spack/packages.yaml`` site configuration.
 
 Here's an example ``packages.yaml`` file that sets preferred packages:
 
@@ -456,7 +307,7 @@ Here's an example ``packages.yaml`` file that sets preferred packages:
        providers:
          mpi: [mvapich2, mpich, openmpi]
 
-At a high level, this example is specifying how packages are preferably
+At a high level, this example is specifying how packages should be
 concretized.  The opencv package should prefer using GCC 4.9 and
 be built with debug options.  The gperftools package should prefer version
 2.2 over 2.4.  Every package on the system should prefer mvapich2 for
@@ -464,11 +315,13 @@ its MPI and GCC 4.4.7 (except for opencv, which overrides this by preferring GCC
 These options are used to fill in implicit defaults.  Any of them can be overwritten
 on the command line if explicitly requested.
 
-Package preferences accept the follow keys or components under
-the specific package (or ``all``) section: ``compiler``, ``variants``,
-``version``, ``providers``, and ``target``.  Each component has an
-ordered list of spec ``constraints``, with earlier entries in the
-list being preferred over later entries.
+Each ``packages.yaml`` file begins with the string ``packages:`` and
+package names are specified on the next level. The special string ``all``
+applies settings to *all* packages. Underneath each package name is one
+or more components: ``compiler``, ``variants``, ``version``,
+``providers``, and ``target``.  Each component has an ordered list of
+spec ``constraints``, with earlier entries in the list being preferred
+over later entries.
 
 Sometimes a package installation may have constraints that forbid
 the first concretization rule, in which case Spack will use the first
@@ -483,9 +336,10 @@ gcc to pgi will thus be preferred over the xlc compiler.
 
 The syntax for the ``provider`` section differs slightly from other
 concretization rules.  A provider lists a value that packages may
-``depends_on`` (e.g, MPI) and a list of rules for fulfilling that
+``depend_on`` (e.g, MPI) and a list of rules for fulfilling that
 dependency.
 
+
 .. _package_permissions:
 
 -------------------
@@ -534,25 +388,3 @@ directories inside the install prefix. This will ensure that even
 manually placed files within the install prefix are owned by the
 assigned group. If no group is assigned, Spack will allow the OS
 default behavior to go as expected.
-
-----------------------------
-Assigning Package Attributes
-----------------------------
-
-You can assign class-level attributes in the configuration:
-
-.. code-block:: yaml
-
-  packages:
-    mpileaks:
-      # Override existing attributes
-      url: http://www.somewhereelse.com/mpileaks-1.0.tar.gz
-      # ... or add new ones
-      x: 1
-
-Attributes set this way will be accessible to any method executed
-in the package.py file (e.g. the ``install()`` method). Values for these
-attributes may be any value parseable by yaml.
-
-These can only be applied to specific packages, not "all" or
-virtual packages.

lib/spack/docs/build_systems.rst

@@ -65,6 +65,7 @@ on these ideas for each distinct build system that Spack supports:
    build_systems/custompackage
    build_systems/inteloneapipackage
    build_systems/intelpackage
+   build_systems/multiplepackage
    build_systems/rocmpackage
    build_systems/sourceforgepackage
 

lib/spack/docs/build_systems/autotoolspackage.rst

@@ -5,9 +5,9 @@
 
 .. _autotoolspackage:
 
----------
-Autotools
----------
+----------------
+AutotoolsPackage
+----------------
 
 Autotools is a GNU build system that provides a build-script generator.
 By running the platform-independent ``./configure`` script that comes
@@ -17,7 +17,7 @@ with the package, you can generate a platform-dependent Makefile.
 Phases
 ^^^^^^
 
-The ``AutotoolsBuilder`` and ``AutotoolsPackage`` base classes come with the following phases:
+The ``AutotoolsPackage`` base class comes with the following phases:
 
 #. ``autoreconf`` - generate the configure script
 #. ``configure`` - generate the Makefiles

lib/spack/docs/build_systems/bundlepackage.rst

@@ -5,9 +5,9 @@
 
 .. _bundlepackage:
 
-------
-Bundle
-------
+-------------
+BundlePackage
+-------------
 
 ``BundlePackage`` represents a set of packages that are expected to work well
 together, such as a collection of commonly used software libraries.  The

lib/spack/docs/build_systems/cachedcmakepackage.rst

@@ -5,9 +5,9 @@
 
 .. _cachedcmakepackage:
 
------------
-CachedCMake
------------
+------------------
+CachedCMakePackage
+------------------
 
 The CachedCMakePackage base class is used for CMake-based workflows
 that create a CMake cache file prior to running ``cmake``. This is

lib/spack/docs/build_systems/cmakepackage.rst

@@ -5,9 +5,9 @@
 
 .. _cmakepackage:
 
------
-CMake
------
+------------
+CMakePackage
+------------
 
 Like Autotools, CMake is a widely-used build-script generator. Designed
 by Kitware, CMake is the most popular build system for new C, C++, and
@@ -21,7 +21,7 @@ whereas Autotools is Unix-only.
 Phases
 ^^^^^^
 
-The ``CMakeBuilder`` and ``CMakePackage`` base classes come with the following phases:
+The ``CMakePackage`` base class comes with the following phases:
 
 #. ``cmake`` - generate the Makefile
 #. ``build`` - build the package
@@ -130,8 +130,8 @@ Adding flags to cmake
 To add additional flags to the ``cmake`` call, simply override the
 ``cmake_args`` function. The following example defines values for the flags
 ``WHATEVER``, ``ENABLE_BROKEN_FEATURE``, ``DETECT_HDF5``, and ``THREADS`` with
-and without the :meth:`~spack.build_systems.cmake.CMakeBuilder.define` and
-:meth:`~spack.build_systems.cmake.CMakeBuilder.define_from_variant` helper functions:
+and without the :meth:`~spack.build_systems.cmake.CMakePackage.define` and
+:meth:`~spack.build_systems.cmake.CMakePackage.define_from_variant` helper functions:
 
 .. code-block:: python
 

lib/spack/docs/build_systems/cudapackage.rst

@@ -5,9 +5,9 @@
 
 .. _cudapackage:
 
-----
-Cuda
-----
+-----------
+CudaPackage
+-----------
 
 Different from other packages, ``CudaPackage`` does not represent a build system.
 Instead its goal is to simplify and unify usage of ``CUDA`` in other packages by providing a `mixin-class <https://en.wikipedia.org/wiki/Mixin>`_.
@@ -80,7 +80,7 @@ standard CUDA compiler flags.
 
 **cuda_flags**
 
-    This built-in static method returns a list of command line flags
+    This built-in static method returns a list of command line flags 
     for the chosen ``cuda_arch`` value(s).  The flags are intended to
     be passed to the CUDA compiler driver (i.e., ``nvcc``).
 

lib/spack/docs/build_systems/inteloneapipackage.rst

@@ -6,9 +6,9 @@
 .. _inteloneapipackage:
 
 
-===========
-IntelOneapi
-===========
+====================
+ IntelOneapiPackage
+====================
 
 
 .. contents::
@@ -32,11 +32,11 @@ oneAPI packages or use::
 
 For more information on a specific package, do::
 
-  spack info --all <package-name>
+  spack info <package-name>
 
 Intel no longer releases new versions of Parallel Studio, which can be
 used in Spack via the :ref:`intelpackage`. All of its components can
-now be found in oneAPI.
+now be found in oneAPI. 
 
 Examples
 ========

lib/spack/docs/build_systems/intelpackage.rst

@@ -5,9 +5,9 @@
 
 .. _intelpackage:
 
------
-Intel
------
+------------
+IntelPackage
+------------
 
 .. contents::
 

lib/spack/docs/build_systems/luapackage.rst

@@ -5,11 +5,11 @@
 
 .. _luapackage:
 
----
-Lua
----
+------------
+LuaPackage
+------------
 
-The ``Lua`` build-system is a helper for the common case of Lua packages that provide
+LuaPackage is a helper for the common case of Lua packages that provide
 a rockspec file.  This is not meant to take a rock archive, but to build
 a source archive or repository that provides a rockspec, which should cover
 most lua packages. In the case a Lua package builds by Make rather than
@@ -19,7 +19,7 @@ luarocks, prefer MakefilePackage.
 Phases
 ^^^^^^
 
-The ``LuaBuilder`` and `LuaPackage`` base classes come with the following phases:
+The ``LuaPackage`` base class comes with the following phases:
 
 #. ``unpack`` - if using a rock, unpacks the rock and moves into the source directory
 #. ``preprocess`` - adjust sources or rockspec to fix build

lib/spack/docs/build_systems/makefilepackage.rst

@@ -5,9 +5,9 @@
 
 .. _makefilepackage:
 
---------
-Makefile
---------
+---------------
+MakefilePackage
+---------------
 
 The most primitive build system a package can use is a plain Makefile.
 Makefiles are simple to write for small projects, but they usually
@@ -18,7 +18,7 @@ variables.
 Phases
 ^^^^^^
 
-The ``MakefileBuilder`` and ``MakefilePackage`` base classes come with 3 phases:
+The ``MakefilePackage`` base class comes with 3 phases:
 
 #. ``edit`` - edit the Makefile
 #. ``build`` - build the project

lib/spack/docs/build_systems/mavenpackage.rst

@@ -5,9 +5,9 @@
 
 .. _mavenpackage:
 
------
-Maven
------
+------------
+MavenPackage
+------------
 
 Apache Maven is a general-purpose build system that does not rely
 on Makefiles to build software. It is designed for building and
@@ -17,7 +17,7 @@ managing and Java-based project.
 Phases
 ^^^^^^
 
-The ``MavenBuilder`` and ``MavenPackage`` base classes come with the following phases:
+The ``MavenPackage`` base class comes with the following phases:
 
 #. ``build`` - compile code and package into a JAR file
 #. ``install`` - copy to installation prefix

lib/spack/docs/build_systems/mesonpackage.rst

@@ -5,9 +5,9 @@
 
 .. _mesonpackage:
 
------
-Meson
------
+------------
+MesonPackage
+------------
 
 Much like Autotools and CMake, Meson is a build system.  But it is
 meant to be both fast and as user friendly as possible.  GNOME's goal
@@ -17,7 +17,7 @@ is to port modules to use the Meson build system.
 Phases
 ^^^^^^
 
-The ``MesonBuilder`` and ``MesonPackage`` base classes come with the following phases:
+The ``MesonPackage`` base class comes with the following phases:
 
 #. ``meson`` - generate ninja files
 #. ``build`` - build the project

lib/spack/docs/build_systems/multiplepackage.rst

@@ -0,0 +1,350 @@
+.. 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)
+
+.. _multiplepackage:
+
+----------------------
+Multiple Build Systems
+----------------------
+
+Quite frequently, a package will change build systems from one version to the
+next. For example, a small project that once used a single Makefile to build
+may now require Autotools to handle the increased number of files that need to
+be compiled. Or, a package that once used Autotools may switch to CMake for
+Windows support. In this case, it becomes a bit more challenging to write a
+single build recipe for this package in Spack.
+
+There are several ways that this can be handled in Spack:
+
+#. Subclass the new build system, and override phases as needed (preferred)
+#. Subclass ``Package`` and implement ``install`` as needed
+#. Create separate ``*-cmake``, ``*-autotools``, etc. packages for each build system
+#. Rename the old package to ``*-legacy`` and create a new package
+#. Move the old package to a ``legacy`` repository and create a new package
+#. Drop older versions that only support the older build system
+
+Of these options, 1 is preferred, and will be demonstrated in this
+documentation. Options 3-5 have issues with concretization, so shouldn't be
+used. Options 4-5 also don't support more than two build systems. Option 6 only
+works if the old versions are no longer needed. Option 1 is preferred over 2
+because it makes it easier to drop the old build system entirely.
+
+The exact syntax of the package depends on which build systems you need to
+support. Below are a couple of common examples.
+
+^^^^^^^^^^^^^^^^^^^^^
+Makefile -> Autotools
+^^^^^^^^^^^^^^^^^^^^^
+
+Let's say we have the following package:
+
+.. code-block:: python
+
+   class Foo(MakefilePackage):
+       version("1.2.0", sha256="...")
+
+       def edit(self, spec, prefix):
+           filter_file("CC=", "CC=" + spack_cc, "Makefile")
+
+       def install(self, spec, prefix):
+           install_tree(".", prefix)
+
+
+The package subclasses from :ref:`makefilepackage`, which has three phases:
+
+#. ``edit`` (does nothing by default)
+#. ``build`` (runs ``make`` by default)
+#. ``install`` (runs ``make install`` by default)
+
+In this case, the ``install`` phase needed to be overridden because the
+Makefile did not have an install target. We also modify the Makefile to use
+Spack's compiler wrappers. The default ``build`` phase is not changed.
+
+Starting with version 1.3.0, we want to use Autotools to build instead.
+:ref:`autotoolspackage` has four phases:
+
+#. ``autoreconf`` (does not if a configure script already exists)
+#. ``configure`` (runs ``./configure --prefix=...`` by default)
+#. ``build`` (runs ``make`` by default)
+#. ``install`` (runs ``make install`` by default)
+
+If the only version we need to support is 1.3.0, the package would look as
+simple as:
+
+.. code-block:: python
+
+   class Foo(AutotoolsPackage):
+       version("1.3.0", sha256="...")
+
+       def configure_args(self):
+           return ["--enable-shared"]
+
+
+In this case, we use the default methods for each phase and only override
+``configure_args`` to specify additional flags to pass to ``./configure``.
+
+If we wanted to write a single package that supports both versions 1.2.0 and
+1.3.0, it would look something like:
+
+.. code-block:: python
+
+   class Foo(AutotoolsPackage):
+       version("1.3.0", sha256="...")
+       version("1.2.0", sha256="...", deprecated=True)
+
+       def configure_args(self):
+           return ["--enable-shared"]
+
+       # Remove the following once version 1.2.0 is dropped
+       @when("@:1.2")
+       def patch(self):
+           filter_file("CC=", "CC=" + spack_cc, "Makefile")
+
+       @when("@:1.2")
+       def autoreconf(self, spec, prefix):
+           pass
+
+       @when("@:1.2")
+       def configure(self, spec, prefix):
+           pass
+
+       @when("@:1.2")
+       def install(self, spec, prefix):
+           install_tree(".", prefix)
+
+
+There are a few interesting things to note here:
+
+* We added ``deprecated=True`` to version 1.2.0. This signifies that version
+  1.2.0 is deprecated and shouldn't be used. However, if a user still relies
+  on version 1.2.0, it's still there and builds just fine.
+* We moved the contents of the ``edit`` phase to the ``patch`` function. Since
+  ``AutotoolsPackage`` doesn't have an ``edit`` phase, the only way for this
+  step to be executed is to move it to the ``patch`` function, which always
+  gets run.
+* The ``autoreconf`` and ``configure`` phases become no-ops. Since the old
+  Makefile-based build system doesn't use these, we ignore these phases when
+  building ``foo@1.2.0``.
+* The ``@when`` decorator is used to override these phases only for older
+  versions. The default methods are used for ``foo@1.3:``.
+
+Once a new Spack release comes out, version 1.2.0 and everything below the
+comment can be safely deleted. The result is the same as if we had written a
+package for version 1.3.0 from scratch.
+
+^^^^^^^^^^^^^^^^^^
+Autotools -> CMake
+^^^^^^^^^^^^^^^^^^
+
+Let's say we have the following package:
+
+.. code-block:: python
+
+   class Bar(AutotoolsPackage):
+       version("1.2.0", sha256="...")
+
+       def configure_args(self):
+           return ["--enable-shared"]
+
+
+The package subclasses from :ref:`autotoolspackage`, which has four phases:
+
+#. ``autoreconf`` (does not if a configure script already exists)
+#. ``configure`` (runs ``./configure --prefix=...`` by default)
+#. ``build`` (runs ``make`` by default)
+#. ``install`` (runs ``make install`` by default)
+
+In this case, we use the default methods for each phase and only override
+``configure_args`` to specify additional flags to pass to ``./configure``.
+
+Starting with version 1.3.0, we want to use CMake to build instead.
+:ref:`cmakepackage` has three phases:
+
+#. ``cmake`` (runs ``cmake ...`` by default)
+#. ``build`` (runs ``make`` by default)
+#. ``install`` (runs ``make install`` by default)
+
+If the only version we need to support is 1.3.0, the package would look as
+simple as:
+
+.. code-block:: python
+
+   class Bar(CMakePackage):
+       version("1.3.0", sha256="...")
+
+       def cmake_args(self):
+           return [self.define("BUILD_SHARED_LIBS", True)]
+
+
+In this case, we use the default methods for each phase and only override
+``cmake_args`` to specify additional flags to pass to ``cmake``.
+
+If we wanted to write a single package that supports both versions 1.2.0 and
+1.3.0, it would look something like:
+
+.. code-block:: python
+
+   class Bar(CMakePackage):
+       version("1.3.0", sha256="...")
+       version("1.2.0", sha256="...", deprecated=True)
+
+       def cmake_args(self):
+           return [self.define("BUILD_SHARED_LIBS", True)]
+
+       # Remove the following once version 1.2.0 is dropped
+       def configure_args(self):
+           return ["--enable-shared"]
+
+       @when("@:1.2")
+       def cmake(self, spec, prefix):
+           configure("--prefix=" + prefix, *self.configure_args())
+
+
+There are a few interesting things to note here:
+
+* We added ``deprecated=True`` to version 1.2.0. This signifies that version
+  1.2.0 is deprecated and shouldn't be used. However, if a user still relies
+  on version 1.2.0, it's still there and builds just fine.
+* Since CMake and Autotools are so similar, we only need to override the
+  ``cmake`` phase, we can use the default ``build`` and ``install`` phases.
+* We override ``cmake`` to run ``./configure`` for older versions.
+  ``configure_args`` remains the same.
+* The ``@when`` decorator is used to override these phases only for older
+  versions. The default methods are used for ``bar@1.3:``.
+
+Once a new Spack release comes out, version 1.2.0 and everything below the
+comment can be safely deleted. The result is the same as if we had written a
+package for version 1.3.0 from scratch.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Multiple build systems for the same version
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+During the transition from one build system to another, developers often
+support multiple build systems at the same time. Spack can only use a single
+build system for a single version. To decide which build system to use for a
+particular version, take the following things into account:
+
+1. If the developers explicitly state that one build system is preferred over
+   another, use that one.
+2. If one build system is considered "experimental" while another is considered
+   "stable", use the stable build system.
+3. Otherwise, use the newer build system.
+
+The developer preference for which build system to use can change over time as
+a newer build system becomes stable/recommended.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Dropping support for old build systems
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When older versions of a package don't support a newer build system, it can be
+tempting to simply delete them from a package. This significantly reduces
+package complexity and makes the build recipe much easier to maintain. However,
+other packages or Spack users may rely on these older versions. The recommended
+approach is to first support both build systems (as demonstrated above),
+:ref:`deprecate <deprecate>` versions that rely on the old build system, and
+remove those versions and any phases that needed to be overridden in the next
+Spack release.
+
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Three or more build systems
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+In rare cases, a package may change build systems multiple times. For example,
+a package may start with Makefiles, then switch to Autotools, then switch to
+CMake. The same logic used above can be extended to any number of build systems.
+For example:
+
+.. code-block:: python
+
+   class Baz(CMakePackage):
+       version("1.4.0", sha256="...")  # CMake
+       version("1.3.0", sha256="...")  # Autotools
+       version("1.2.0", sha256="...")  # Makefile
+
+       def cmake_args(self):
+           return [self.define("BUILD_SHARED_LIBS", True)]
+
+       # Remove the following once version 1.3.0 is dropped
+       def configure_args(self):
+           return ["--enable-shared"]
+
+       @when("@1.3")
+       def cmake(self, spec, prefix):
+           configure("--prefix=" + prefix, *self.configure_args())
+
+       # Remove the following once version 1.2.0 is dropped
+       @when("@:1.2")
+       def patch(self):
+           filter_file("CC=", "CC=" + spack_cc, "Makefile")
+
+       @when("@:1.2")
+       def cmake(self, spec, prefix):
+           pass
+
+       @when("@:1.2")
+       def install(self, spec, prefix):
+           install_tree(".", prefix)
+
+
+^^^^^^^^^^^^^^^^^^^
+Additional examples
+^^^^^^^^^^^^^^^^^^^
+
+When writing new packages, it often helps to see examples of existing packages.
+Here is an incomplete list of existing Spack packages that have changed build
+systems before:
+
+================  =====================  ================
+Package           Previous Build System  New Build System
+================  =====================  ================
+amber             custom                 CMake
+arpack-ng         Autotools              CMake
+atk               Autotools              Meson
+blast             None                   Autotools
+dyninst           Autotools              CMake
+evtgen            Autotools              CMake
+fish              Autotools              CMake
+gdk-pixbuf        Autotools              Meson
+glib              Autotools              Meson
+glog              Autotools              CMake
+gmt               Autotools              CMake
+gtkplus           Autotools              Meson
+hpl               Makefile               Autotools
+interproscan      Perl                   Maven
+jasper            Autotools              CMake
+kahip             SCons                  CMake
+kokkos            Makefile               CMake
+kokkos-kernels    Makefile               CMake
+leveldb           Makefile               CMake
+libdrm            Autotools              Meson
+libjpeg-turbo     Autotools              CMake
+mesa              Autotools              Meson
+metis             None                   CMake
+mpifileutils      Autotools              CMake
+muparser          Autotools              CMake
+mxnet             Makefile               CMake
+nest              Autotools              CMake
+neuron            Autotools              CMake
+nsimd             CMake                  nsconfig
+opennurbs         Makefile               CMake
+optional-lite     None                   CMake
+plasma            Makefile               CMake
+preseq            Makefile               Autotools
+protobuf          Autotools              CMake
+py-pygobject      Autotools              Python
+singularity       Autotools              Makefile
+span-lite         None                   CMake
+ssht              Makefile               CMake
+string-view-lite  None                   CMake
+superlu           Makefile               CMake
+superlu-dist      Makefile               CMake
+uncrustify        Autotools              CMake
+================  =====================  ================
+
+Packages that support multiple build systems can be a bit confusing to write.
+Don't hesitate to open an issue or draft pull request and ask for advice from
+other Spack developers!

lib/spack/docs/build_systems/octavepackage.rst

@@ -5,9 +5,9 @@
 
 .. _octavepackage:
 
-------
-Octave
-------
+-------------
+OctavePackage
+-------------
 
 Octave has its own build system for installing packages.
 
@@ -15,7 +15,7 @@ Octave has its own build system for installing packages.
 Phases
 ^^^^^^
 
-The ``OctaveBuilder`` and ``OctavePackage`` base classes have a single phase:
+The ``OctavePackage`` base class has a single phase:
 
 #. ``install`` - install the package
 

lib/spack/docs/build_systems/perlpackage.rst

@@ -5,9 +5,9 @@
 
 .. _perlpackage:
 
-----
-Perl
-----
+-----------
+PerlPackage
+-----------
 
 Much like Octave, Perl has its own language-specific
 build system.
@@ -16,7 +16,7 @@ build system.
 Phases
 ^^^^^^
 
-The ``PerlBuilder`` and ``PerlPackage`` base classes come with 3 phases that can be overridden:
+The ``PerlPackage`` base class comes with 3 phases that can be overridden:
 
 #. ``configure`` - configure the package
 #. ``build`` - build the package

lib/spack/docs/build_systems/pythonpackage.rst

@@ -5,9 +5,9 @@
 
 .. _pythonpackage:
 
-------
-Python
-------
+-------------
+PythonPackage
+-------------
 
 Python packages and modules have their own special build system. This
 documentation covers everything you'll need to know in order to write
@@ -48,11 +48,9 @@ important to understand.
 **build backend**
    Libraries used to define how to build a wheel. Examples
    include `setuptools <https://setuptools.pypa.io/>`__,
-   `flit <https://flit.pypa.io/>`_,
-   `poetry <https://python-poetry.org/>`_,
-   `hatchling <https://hatch.pypa.io/latest/>`_,
-   `meson <https://meson-python.readthedocs.io/>`_, and
-   `pdm <https://pdm.fming.dev/latest/>`_.
+   `flit <https://flit.readthedocs.io/>`_,
+   `poetry <https://python-poetry.org/>`_, and
+   `hatchling <https://hatch.pypa.io/latest/>`_.
 
 ^^^^^^^^^^^
 Downloading
@@ -176,9 +174,9 @@ 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.
 
-^^^^^^^^^^^^
-Dependencies
-^^^^^^^^^^^^
+^^^^^^^^^^^^^
+Build backend
+^^^^^^^^^^^^^
 
 Once you've determined the basic metadata for a package, the next
 step is to determine the build backend. ``PythonPackage`` uses
@@ -216,33 +214,12 @@ Note that ``py-wheel`` is already listed as a build dependency in the
 need to specify a specific version requirement or change the
 dependency type.
 
-See `PEP 517 <https://www.python.org/dev/peps/pep-0517/>`__ and
+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``.
 
 Depending on which build backend a project uses, there are various
-places that run-time dependencies can be listed. Most modern build
-backends support listing dependencies directly in ``pyproject.toml``.
-Look for dependencies under the following keys:
-
-* ``requires-python`` under ``[project]``
-
-  This specifies the version of Python that is required
-
-* ``dependencies`` under ``[project]``
-
-  These packages are required for building and installation. You can
-  add them with ``type=('build', 'run')``.
-
-* ``[project.optional-dependencies]``
-
-  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.
-
-Some build backends may have additional locations where dependencies
-can be found.
+places that run-time dependencies can be listed.
 
 """""""""
 distutils
@@ -268,9 +245,9 @@ 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. In addition to
-``pyproject.toml``, dependencies can be listed in the ``setup.py`` or
-``setup.cfg`` file. Look for the following arguments:
+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``
 
@@ -315,22 +292,25 @@ 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.
 
-In addition to the default ``pyproject.toml`` keys listed above,
-older versions of flit may use the following keys:
+Either of these files may contain keys like:
 
-* ``requires`` under ``[tool.flit.metadata]``
+* ``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')``.
 
-* ``[tool.flit.metadata.requires-extra]``
+* ``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.pypa.io/en/latest/pyproject_toml.html for
+See https://flit.readthedocs.io/en/latest/pyproject_toml.html for
 more information.
 
 """"""
@@ -352,33 +332,28 @@ hatchling
 """""""""
 
 If the ``pyproject.toml`` lists ``hatchling.build`` as the
-``build-backend``, it uses the hatchling build system. Hatchling
-uses the default ``pyproject.toml`` keys to list dependencies.
+``build-backend``, it uses the hatchling build system. Look for
+dependencies under the following keys:
+
+* ``requires-python``
+
+  This specifies the version of Python that is required
+
+* ``project.dependencies``
+
+  These packages are required for building and installation. You can
+  add them with ``type=('build', 'run')``.
+
+* ``project.optional-dependencies``
+
+  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://hatch.pypa.io/latest/config/dependency/ for more
 information.
 
-"""""
-meson
-"""""
-
-If the ``pyproject.toml`` lists ``mesonpy`` as the ``build-backend``,
-it uses the meson build system. Meson uses the default
-``pyproject.toml`` keys to list dependencies.
-
-See https://meson-python.readthedocs.io/en/latest/usage/start.html
-for more information.
-
-"""
-pdm
-"""
-
-If the ``pyproject.toml`` lists ``pdm.pep517.api`` as the ``build-backend``,
-it uses the PDM build system. PDM uses the default ``pyproject.toml``
-keys to list dependencies.
-
-See https://pdm.fming.dev/latest/ for more information.
-
 """"""
 wheels
 """"""
@@ -423,34 +398,6 @@ 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.
 
-"""""""""""""""
-Config settings
-"""""""""""""""
-
-These settings are passed to
-`PEP 517 <https://peps.python.org/pep-0517/>`__ build backends.
-For example, ``py-scipy`` package allows you to specify the name of
-the BLAS/LAPACK library you want pkg-config to search for:
-
-.. code-block:: python
-
-   depends_on('py-pip@22.1:', type='build')
-
-   def config_settings(self, spec, prefix):
-       return {
-           'blas': spec['blas'].libs.names[0],
-           'lapack': spec['lapack'].libs.names[0],
-       }
-
-
-.. note::
-
-   This flag only works for packages that define a ``build-backend``
-   in ``pyproject.toml``. Also, it is only supported by pip 22.1+,
-   which requires Python 3.7+. For packages that still support Python
-   3.6 and older, ``install_options`` should be used instead.
-
-
 """"""""""""""
 Global options
 """"""""""""""
@@ -470,16 +417,6 @@ has an optional dependency on ``libyaml`` that can be enabled like so:
        return options
 
 
-.. note::
-
-   Direct invocation of ``setup.py`` is
-   `deprecated <https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html>`_.
-   This flag forces pip to use a deprecated installation procedure.
-   It should only be used in packages that don't define a
-   ``build-backend`` in ``pyproject.toml`` or packages that still
-   support Python 3.6 and older.
-
-
 """""""""""""""
 Install options
 """""""""""""""
@@ -500,16 +437,6 @@ allows you to specify the directories to search for ``libyaml``:
        return options
 
 
-.. note::
-
-   Direct invocation of ``setup.py`` is
-   `deprecated <https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html>`_.
-   This flag forces pip to use a deprecated installation procedure.
-   It should only be used in packages that don't define a
-   ``build-backend`` in ``pyproject.toml`` or packages that still
-   support Python 3.6 and older.
-
-
 ^^^^^^^
 Testing
 ^^^^^^^
@@ -582,19 +509,6 @@ libraries. Make sure not to add modules/packages containing the word
 "test", as these likely won't end up in the installation directory,
 or may require test dependencies like pytest to be installed.
 
-Instead of defining the ``import_modules`` explicity, only the subset
-of module names to be skipped can be defined by using ``skip_modules``.
-If a defined module has submodules, they are skipped as well, e.g.,
-in case the ``plotting`` modules should be excluded from the
-automatically detected ``import_modules`` ``['nilearn', 'nilearn.surface',
-'nilearn.plotting', 'nilearn.plotting.data']`` set:
-
-.. code-block:: python
-
-        skip_modules = ['nilearn.plotting']
-
-This will set ``import_modules`` to ``['nilearn', 'nilearn.surface']``
-
 Import tests can be run during the installation using ``spack install
 --test=root`` or at any time after the installation using
 ``spack test run``.
@@ -724,9 +638,10 @@ extends vs. depends_on
 
 This is very similar to the naming dilemma above, with a slight twist.
 As mentioned in the :ref:`Packaging Guide <packaging_extensions>`,
-``extends`` and ``depends_on`` are very similar, but ``extends`` ensures
-that the extension and extendee share the same prefix in views.
-This allows the user to import a Python module without
+``extends`` and ``depends_on`` are very similar, but ``extends`` adds
+the ability to *activate* the package. Activation involves symlinking
+everything in the installation prefix of the package to the installation
+prefix of Python. This allows the user to import a Python module without
 having to add that module to ``PYTHONPATH``.
 
 When deciding between ``extends`` and ``depends_on``, the best rule of
@@ -734,7 +649,7 @@ thumb is to check the installation prefix. If Python libraries are
 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``.
+don't use ``extends``, as symlinking the package wouldn't be useful.
 
 ^^^^^^^^^^^^^^^^^^^^^
 Alternatives to Spack
@@ -777,8 +692,6 @@ For more information on build and installation frontend tools, see:
 For more information on build backend tools, see:
 
 * setuptools: https://setuptools.pypa.io/
-* flit: https://flit.pypa.io/
+* flit: https://flit.readthedocs.io/
 * poetry: https://python-poetry.org/
 * hatchling: https://hatch.pypa.io/latest/
-* meson: https://meson-python.readthedocs.io/
-* pdm: https://pdm.fming.dev/latest/

lib/spack/docs/build_systems/qmakepackage.rst

@@ -5,9 +5,9 @@
 
 .. _qmakepackage:
 
------
-QMake
------
+------------
+QMakePackage
+------------
 
 Much like Autotools and CMake, QMake is a build-script generator
 designed by the developers of Qt. In its simplest form, Spack's
@@ -29,7 +29,7 @@ variables or edit ``*.pro`` files to get things working properly.
 Phases
 ^^^^^^
 
-The ``QMakeBuilder`` and ``QMakePackage`` base classes come with the following phases:
+The ``QMakePackage`` base class comes with the following phases:
 
 #. ``qmake`` - generate Makefiles
 #. ``build`` - build the project

lib/spack/docs/build_systems/racketpackage.rst

@@ -5,9 +5,9 @@
 
 .. _racketpackage:
 
-------
-Racket
-------
+-------------
+RacketPackage
+-------------
 
 Much like Python, Racket packages and modules have their own special build system.
 To learn more about the specifics of Racket package system, please refer to the
@@ -17,7 +17,7 @@ To learn more about the specifics of Racket package system, please refer to the
 Phases
 ^^^^^^
 
-The ``RacketBuilder`` and ``RacketPackage`` base classes provides an ``install`` phase that
+The ``RacketPackage`` base class provides an ``install`` phase that
 can be overridden, corresponding to the use of:
 
 .. code-block:: console

lib/spack/docs/build_systems/rocmpackage.rst

@@ -5,9 +5,9 @@
 
 .. _rocmpackage:
 
-----
-ROCm
-----
+-----------
+ROCmPackage
+-----------
 
 The ``ROCmPackage`` is not a build system but a helper package. Like ``CudaPackage``,
 it provides standard variants, dependencies, and conflicts to facilitate building
@@ -25,7 +25,7 @@ This package provides the following variants:
 
 * **rocm**
 
-  This variant is used to enable/disable building with ``rocm``.
+  This variant is used to enable/disable building with ``rocm``.  
   The default is disabled (or ``False``).
 
 * **amdgpu_target**

lib/spack/docs/build_systems/rpackage.rst

@@ -5,9 +5,9 @@
 
 .. _rpackage:
 
---
-R
---
+--------
+RPackage
+--------
 
 Like Python, R has its own built-in build system.
 
@@ -19,7 +19,7 @@ new Spack packages for.
 Phases
 ^^^^^^
 
-The ``RBuilder`` and ``RPackage`` base classes have a single phase:
+The ``RPackage`` base class has a single phase:
 
 #. ``install`` - install the package
 
@@ -193,10 +193,10 @@ Build system dependencies
 
 As an extension of the R ecosystem, your package will obviously depend
 on R to build and run. Normally, we would use ``depends_on`` to express
-this, but for R packages, we use ``extends``. This implies a special
-dependency on R, which is used to set environment variables such as
-``R_LIBS`` uniformly. Since every R package needs this, the ``RPackage``
-base class contains:
+this, but for R packages, we use ``extends``. ``extends`` is similar to
+``depends_on``, but adds an additional feature: the ability to "activate"
+the package by symlinking it to the R installation directory. Since
+every R package needs this, the ``RPackage`` base class contains:
 
 .. code-block:: python
 

lib/spack/docs/build_systems/rubypackage.rst

@@ -5,9 +5,9 @@
 
 .. _rubypackage:
 
-----
-Ruby
-----
+-----------
+RubyPackage
+-----------
 
 Like Perl, Python, and R, Ruby has its own build system for
 installing Ruby gems.
@@ -16,7 +16,7 @@ installing Ruby gems.
 Phases
 ^^^^^^
 
-The ``RubyBuilder`` and ``RubyPackage`` base classes provide the following phases that
+The ``RubyPackage`` base class provides the following phases that
 can be overridden:
 
 #. ``build`` - build everything needed to install

lib/spack/docs/build_systems/sconspackage.rst

@@ -5,9 +5,9 @@
 
 .. _sconspackage:
 
------
-SCons
------
+------------
+SConsPackage
+------------
 
 SCons is a general-purpose build system that does not rely on
 Makefiles to build software. SCons is written in Python, and handles
@@ -42,7 +42,7 @@ As previously mentioned, SCons allows developers to add subcommands like
    $ scons install
 
 
-To facilitate this, the ``SConsBuilder`` and ``SconsPackage`` base classes provide the
+To facilitate this, the ``SConsPackage`` base class provides the
 following phases:
 
 #. ``build`` - build the package

lib/spack/docs/build_systems/sippackage.rst

@@ -5,9 +5,9 @@
 
 .. _sippackage:
 
----
-SIP
----
+----------
+SIPPackage
+----------
 
 SIP is a tool that makes it very easy to create Python bindings for C and C++
 libraries. It was originally developed to create PyQt, the Python bindings for
@@ -22,7 +22,7 @@ provides support functions to the automatically generated code.
 Phases
 ^^^^^^
 
-The ``SIPBuilder`` and ``SIPPackage`` base classes come with the following phases:
+The ``SIPPackage`` base class comes with the following phases:
 
 #. ``configure`` - configure the package
 #. ``build`` - build the package

lib/spack/docs/build_systems/sourceforgepackage.rst

@@ -5,15 +5,15 @@
 
 .. _sourceforgepackage:
 
------------
-Sourceforge
------------
+------------------
+SourceforgePackage
+------------------
 
-``SourceforgePackage`` is a
+``SourceforgePackage`` is a 
 `mixin-class <https://en.wikipedia.org/wiki/Mixin>`_. It automatically
 sets the URL based on a list of Sourceforge mirrors listed in
 `sourceforge_mirror_path`, which defaults to a half dozen known mirrors.
-Refer to the package source
+Refer to the package source 
 (`<https://github.com/spack/spack/blob/develop/lib/spack/spack/build_systems/sourceforge.py>`__) for the current list of mirrors used by Spack.
 
 
@@ -29,7 +29,7 @@ This package provides a method for populating mirror URLs.
     It is decorated with `property` so its results are treated as
     a package attribute.
 
-    Refer to
+    Refer to 
     `<https://spack.readthedocs.io/en/latest/packaging_guide.html#mirrors-of-the-main-url>`__
     for information on how Spack uses the `urls` attribute during
     fetching.

lib/spack/docs/build_systems/wafpackage.rst

@@ -5,9 +5,9 @@
 
 .. _wafpackage:
 
----
-Waf
----
+----------
+WafPackage
+----------
 
 Like SCons, Waf is a general-purpose build system that does not rely
 on Makefiles to build software.
@@ -16,7 +16,7 @@ on Makefiles to build software.
 Phases
 ^^^^^^
 
-The ``WafBuilder`` and ``WafPackage`` base classes come with the following phases:
+The ``WafPackage`` base class comes with the following phases:
 
 #. ``configure`` - configure the project
 #. ``build`` - build the project

lib/spack/docs/conf.py

@@ -32,36 +32,37 @@
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
-link_name = os.path.abspath("_spack_root")
-if not os.path.exists(link_name):
-    os.symlink(os.path.abspath("../../.."), link_name, target_is_directory=True)
-sys.path.insert(0, os.path.abspath("_spack_root/lib/spack/external"))
-sys.path.insert(0, os.path.abspath("_spack_root/lib/spack/external/pytest-fallback"))
-sys.path.append(os.path.abspath("_spack_root/lib/spack/"))
+sys.path.insert(0, os.path.abspath('_spack_root/lib/spack/external'))
+sys.path.insert(0, os.path.abspath('_spack_root/lib/spack/external/pytest-fallback'))
+
+if sys.version_info[0] < 3:
+    sys.path.insert(
+        0, os.path.abspath('_spack_root/lib/spack/external/yaml/lib'))
+else:
+    sys.path.insert(
+        0, os.path.abspath('_spack_root/lib/spack/external/yaml/lib3'))
+
+sys.path.append(os.path.abspath('_spack_root/lib/spack/'))
 
 # Add the Spack bin directory to the path so that we can use its output in docs.
-os.environ["SPACK_ROOT"] = os.path.abspath("_spack_root")
-os.environ["PATH"] += "%s%s" % (os.pathsep, os.path.abspath("_spack_root/bin"))
+os.environ['SPACK_ROOT'] = os.path.abspath('_spack_root')
+os.environ['PATH'] += "%s%s" % (os.pathsep, os.path.abspath('_spack_root/bin'))
 
 # Set an environment variable so that colify will print output like it would to
 # a terminal.
-os.environ["COLIFY_SIZE"] = "25x120"
-os.environ["COLUMNS"] = "120"
+os.environ['COLIFY_SIZE'] = '25x120'
+os.environ['COLUMNS'] = '120'
 
 # Generate full package list if needed
-subprocess.call(["spack", "list", "--format=html", "--update=package_list.html"])
+subprocess.call([
+    'spack', 'list', '--format=html', '--update=package_list.html'])
 
 # Generate a command index if an update is needed
-subprocess.call(
-    [
-        "spack",
-        "commands",
-        "--format=rst",
-        "--header=command_index.in",
-        "--update=command_index.rst",
-    ]
-    + glob("*rst")
-)
+subprocess.call([
+    'spack', 'commands',
+    '--format=rst',
+    '--header=command_index.in',
+    '--update=command_index.rst'] + glob('*rst'))
 
 #
 # Run sphinx-apidoc
@@ -71,12 +72,12 @@
 # Without this, the API Docs will never actually update
 #
 apidoc_args = [
-    "--force",  # Overwrite existing files
-    "--no-toc",  # Don't create a table of contents file
-    "--output-dir=.",  # Directory to place all output
+    '--force',         # Overwrite existing files
+    '--no-toc',        # Don't create a table of contents file
+    '--output-dir=.',  # Directory to place all output
 ]
-sphinx_apidoc(apidoc_args + ["_spack_root/lib/spack/spack"])
-sphinx_apidoc(apidoc_args + ["_spack_root/lib/spack/llnl"])
+sphinx_apidoc(apidoc_args + ['_spack_root/lib/spack/spack'])
+sphinx_apidoc(apidoc_args + ['_spack_root/lib/spack/llnl'])
 
 # Enable todo items
 todo_include_todos = True
@@ -86,12 +87,10 @@
 #
 class PatchedPythonDomain(PythonDomain):
     def resolve_xref(self, env, fromdocname, builder, typ, target, node, contnode):
-        if "refspecific" in node:
-            del node["refspecific"]
+        if 'refspecific' in node:
+            del node['refspecific']
         return super(PatchedPythonDomain, self).resolve_xref(
-            env, fromdocname, builder, typ, target, node, contnode
-        )
-
+            env, fromdocname, builder, typ, target, node, contnode)
 
 #
 # Disable tabs to space expansion in code blocks
@@ -104,58 +103,51 @@ def parse(self, inputstring, document):
             inputstring = StringList(lines, document.current_source)
         super().parse(inputstring, document)
 
-
 def setup(sphinx):
     sphinx.add_domain(PatchedPythonDomain, override=True)
     sphinx.add_source_parser(NoTabExpansionRSTParser, override=True)
 
-
 # -- General configuration -----------------------------------------------------
 
 # If your documentation needs a minimal Sphinx version, state it here.
-needs_sphinx = "3.4"
+needs_sphinx = '3.4'
 
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
 extensions = [
-    "sphinx.ext.autodoc",
-    "sphinx.ext.graphviz",
-    "sphinx.ext.intersphinx",
-    "sphinx.ext.napoleon",
-    "sphinx.ext.todo",
-    "sphinx.ext.viewcode",
-    "sphinx_design",
-    "sphinxcontrib.programoutput",
+    'sphinx.ext.autodoc',
+    'sphinx.ext.graphviz',
+    'sphinx.ext.intersphinx',
+    'sphinx.ext.napoleon',
+    'sphinx.ext.todo',
+    'sphinx.ext.viewcode',
+    'sphinxcontrib.programoutput',
 ]
 
 # Set default graphviz options
 graphviz_dot_args = [
-    "-Grankdir=LR",
-    "-Gbgcolor=transparent",
-    "-Nshape=box",
-    "-Nfontname=monaco",
-    "-Nfontsize=10",
-]
+    '-Grankdir=LR', '-Gbgcolor=transparent',
+    '-Nshape=box', '-Nfontname=monaco', '-Nfontsize=10']
 
 # Get nice vector graphics
 graphviz_output_format = "svg"
 
 
 # Add any paths that contain templates here, relative to this directory.
-templates_path = ["_templates"]
+templates_path = ['_templates']
 
 # The suffix of source filenames.
-source_suffix = ".rst"
+source_suffix = '.rst'
 
 # The encoding of source files.
-source_encoding = "utf-8-sig"
+source_encoding = 'utf-8-sig'
 
 # The master toctree document.
-master_doc = "index"
+master_doc = 'index'
 
 # General information about the project.
-project = "Spack"
-copyright = "2013-2021, Lawrence Livermore National Laboratory."
+project = u'Spack'
+copyright = u'2013-2021, Lawrence Livermore National Laboratory.'
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
@@ -164,16 +156,16 @@ def setup(sphinx):
 # The short X.Y version.
 import spack
 
-version = ".".join(str(s) for s in spack.spack_version_info[:2])
+version = '.'.join(str(s) for s in spack.spack_version_info[:2])
 # The full version, including alpha/beta/rc tags.
 release = spack.spack_version
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
-# language = None
+#language = None
 
 # Places to look for .po/.mo files for doc translations
-# locale_dirs = []
+#locale_dirs = []
 
 # Sphinx gettext settings
 gettext_compact = True
@@ -181,46 +173,41 @@ def setup(sphinx):
 
 # There are two options for replacing |today|: either, you set today to some
 # non-false value, then it is used:
-# today = ''
+#today = ''
 # Else, today_fmt is used as the format for a strftime call.
-# today_fmt = '%B %d, %Y'
+#today_fmt = '%B %d, %Y'
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
-exclude_patterns = ["_build", "_spack_root", ".spack-env"]
+exclude_patterns = ['_build', '_spack_root', '.spack-env']
 
 nitpicky = True
 nitpick_ignore = [
     # Python classes that intersphinx is unable to resolve
-    ("py:class", "argparse.HelpFormatter"),
-    ("py:class", "contextlib.contextmanager"),
-    ("py:class", "module"),
-    ("py:class", "_io.BufferedReader"),
-    ("py:class", "unittest.case.TestCase"),
-    ("py:class", "_frozen_importlib_external.SourceFileLoader"),
-    ("py:class", "clingo.Control"),
-    ("py:class", "six.moves.urllib.parse.ParseResult"),
+    ('py:class', 'argparse.HelpFormatter'),
+    ('py:class', 'contextlib.contextmanager'),
+    ('py:class', 'module'),
+    ('py:class', '_io.BufferedReader'),
+    ('py:class', 'unittest.case.TestCase'),
+    ('py:class', '_frozen_importlib_external.SourceFileLoader'),
     # Spack classes that are private and we don't want to expose
-    ("py:class", "spack.provider_index._IndexBase"),
-    ("py:class", "spack.repo._PrependFileLoader"),
-    ("py:class", "spack.build_systems._checks.BaseBuilder"),
-    # Spack classes that intersphinx is unable to resolve
-    ("py:class", "spack.version.VersionBase"),
+    ('py:class', 'spack.provider_index._IndexBase'),
+    ('py:class', 'spack.repo._PrependFileLoader'),
 ]
 
 # The reST default role (used for this markup: `text`) to use for all documents.
-# default_role = None
+#default_role = None
 
 # If true, '()' will be appended to :func: etc. cross-reference text.
-# add_function_parentheses = True
+#add_function_parentheses = True
 
 # If true, the current module name will be prepended to all description
 # unit titles (such as .. function::).
-# add_module_names = True
+#add_module_names = True
 
 # If true, sectionauthor and moduleauthor directives will be shown in the
 # output. They are ignored by default.
-# show_authors = False
+#show_authors = False
 
 # The name of the Pygments (syntax highlighting) style to use.
 # We use our own extension of the default style with a few modifications
@@ -231,151 +218,156 @@ def setup(sphinx):
 
 class SpackStyle(DefaultStyle):
     styles = DefaultStyle.styles.copy()
-    background_color = "#f4f4f8"
+    background_color       = "#f4f4f8"
     styles[Generic.Output] = "#355"
     styles[Generic.Prompt] = "bold #346ec9"
 
-
 import pkg_resources
 
 dist = pkg_resources.Distribution(__file__)
-sys.path.append(".")  # make 'conf' module findable
-ep = pkg_resources.EntryPoint.parse("spack = conf:SpackStyle", dist=dist)
-dist._ep_map = {"pygments.styles": {"plugin1": ep}}
+sys.path.append('.')  # make 'conf' module findable
+ep = pkg_resources.EntryPoint.parse('spack = conf:SpackStyle', dist=dist)
+dist._ep_map = {'pygments.styles': {'plugin1': ep}}
 pkg_resources.working_set.add(dist)
 
-pygments_style = "spack"
+pygments_style = 'spack'
 
 # A list of ignored prefixes for module index sorting.
-# modindex_common_prefix = []
+#modindex_common_prefix = []
 
 
 # -- Options for HTML output ---------------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = "sphinx_rtd_theme"
+html_theme = 'sphinx_rtd_theme'
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
 # documentation.
-html_theme_options = {"logo_only": True}
+html_theme_options = { 'logo_only' : True }
 
 # Add any paths that contain custom themes here, relative to this directory.
 # html_theme_path = ["_themes"]
 
 # The name for this set of Sphinx documents.  If None, it defaults to
 # "<project> v<release> documentation".
-# html_title = None
+#html_title = None
 
 # A shorter title for the navigation bar.  Default is the same as html_title.
-# html_short_title = None
+#html_short_title = None
 
 # The name of an image file (relative to this directory) to place at the top
 # of the sidebar.
-html_logo = "_spack_root/share/spack/logo/spack-logo-white-text.svg"
+html_logo = '_spack_root/share/spack/logo/spack-logo-white-text.svg'
 
 # The name of an image file (within the static path) to use as favicon of the
 # docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
 # pixels large.
-html_favicon = "_spack_root/share/spack/logo/favicon.ico"
+html_favicon = '_spack_root/share/spack/logo/favicon.ico'
 
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ["_static"]
+html_static_path = ['_static']
 
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.
-html_last_updated_fmt = "%b %d, %Y"
+html_last_updated_fmt = '%b %d, %Y'
 
 # If true, SmartyPants will be used to convert quotes and dashes to
 # typographically correct entities.
-# html_use_smartypants = True
+#html_use_smartypants = True
 
 # Custom sidebar templates, maps document names to template names.
-# html_sidebars = {}
+#html_sidebars = {}
 
 # Additional templates that should be rendered to pages, maps page names to
 # template names.
-# html_additional_pages = {}
+#html_additional_pages = {}
 
 # If false, no module index is generated.
-# html_domain_indices = True
+#html_domain_indices = True
 
 # If false, no index is generated.
-# html_use_index = True
+#html_use_index = True
 
 # If true, the index is split into individual pages for each letter.
-# html_split_index = False
+#html_split_index = False
 
 # If true, links to the reST sources are added to the pages.
-# html_show_sourcelink = True
+#html_show_sourcelink = True
 
 # If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
-# html_show_sphinx = False
+#html_show_sphinx = False
 
 # If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
-# html_show_copyright = True
+#html_show_copyright = True
 
 # If true, an OpenSearch description file will be output, and all pages will
 # contain a <link> tag referring to it.  The value of this option must be the
 # base URL from which the finished HTML is served.
-# html_use_opensearch = ''
+#html_use_opensearch = ''
 
 # This is the file name suffix for HTML files (e.g. ".xhtml").
-# html_file_suffix = None
+#html_file_suffix = None
 
 # Output file base name for HTML help builder.
-htmlhelp_basename = "Spackdoc"
+htmlhelp_basename = 'Spackdoc'
 
 
 # -- Options for LaTeX output --------------------------------------------------
 
 latex_elements = {
-    # The paper size ('letterpaper' or 'a4paper').
-    #'papersize': 'letterpaper',
-    # The font size ('10pt', '11pt' or '12pt').
-    #'pointsize': '10pt',
-    # Additional stuff for the LaTeX preamble.
-    #'preamble': '',
+# The paper size ('letterpaper' or 'a4paper').
+#'papersize': 'letterpaper',
+
+# The font size ('10pt', '11pt' or '12pt').
+#'pointsize': '10pt',
+
+# Additional stuff for the LaTeX preamble.
+#'preamble': '',
 }
 
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title, author, documentclass [howto/manual]).
 latex_documents = [
-    ("index", "Spack.tex", "Spack Documentation", "Todd Gamblin", "manual"),
+  ('index', 'Spack.tex', u'Spack Documentation',
+   u'Todd Gamblin', 'manual'),
 ]
 
 # The name of an image file (relative to this directory) to place at the top of
 # the title page.
-# latex_logo = None
+#latex_logo = None
 
 # For "manual" documents, if this is true, then toplevel headings are parts,
 # not chapters.
-# latex_use_parts = False
+#latex_use_parts = False
 
 # If true, show page references after internal links.
-# latex_show_pagerefs = False
+#latex_show_pagerefs = False
 
 # If true, show URL addresses after external links.
-# latex_show_urls = False
+#latex_show_urls = False
 
 # Documents to append as an appendix to all manuals.
-# latex_appendices = []
+#latex_appendices = []
 
 # If false, no module index is generated.
-# latex_domain_indices = True
+#latex_domain_indices = True
 
 
 # -- Options for manual page output --------------------------------------------
 
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
-man_pages = [("index", "spack", "Spack Documentation", ["Todd Gamblin"], 1)]
+man_pages = [
+    ('index', 'spack', u'Spack Documentation',
+     [u'Todd Gamblin'], 1)
+]
 
 # If true, show URL addresses after external links.
-# man_show_urls = False
+#man_show_urls = False
 
 
 # -- Options for Texinfo output ------------------------------------------------
@@ -384,25 +376,19 @@ class SpackStyle(DefaultStyle):
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-    (
-        "index",
-        "Spack",
-        "Spack Documentation",
-        "Todd Gamblin",
-        "Spack",
-        "One line description of project.",
-        "Miscellaneous",
-    ),
+  ('index', 'Spack', u'Spack Documentation',
+   u'Todd Gamblin', 'Spack', 'One line description of project.',
+   'Miscellaneous'),
 ]
 
 # Documents to append as an appendix to all manuals.
-# texinfo_appendices = []
+#texinfo_appendices = []
 
 # If false, no module index is generated.
-# texinfo_domain_indices = True
+#texinfo_domain_indices = True
 
 # How to display URL addresses: 'footnote', 'no', or 'inline'.
-# texinfo_show_urls = 'footnote'
+#texinfo_show_urls = 'footnote'
 
 
 # -- Extension configuration -------------------------------------------------

lib/spack/docs/config_yaml.rst

@@ -19,9 +19,9 @@ see the default settings by looking at
 These settings can be overridden in ``etc/spack/config.yaml`` or
 ``~/.spack/config.yaml``.  See :ref:`configuration-scopes` for details.
 
----------------------
-``install_tree:root``
----------------------
+--------------------
+``install_tree``
+--------------------
 
 The location where Spack will install packages and their dependencies.
 Default is ``$spack/opt/spack``.
@@ -224,9 +224,9 @@ them). Please note that we currently disable ccache's ``hash_dir``
 feature to avoid an issue with the stage directory (see
 https://github.com/LLNL/spack/pull/3761#issuecomment-294352232).
 
------------------------
-``shared_linking:type``
------------------------
+------------------
+``shared_linking``
+------------------
 
 Control whether Spack embeds ``RPATH`` or ``RUNPATH`` attributes in ELF binaries
 so that they can find their dependencies. Has no effect on macOS.
@@ -245,52 +245,6 @@ the loading object.
 
 DO NOT MIX the two options within the same install tree.
 
------------------------
-``shared_linking:bind``
------------------------
-
-This is an *experimental option* that controls whether Spack embeds absolute paths
-to needed shared libraries in ELF executables and shared libraries on Linux. Setting
-this option to ``true`` has two advantages:
-
-1. **Improved startup time**: when running an executable, the dynamic loader does not
-   have to perform a search for needed libraries, they are loaded directly.
-2. **Reliability**: libraries loaded at runtime are those that were linked to. This
-   minimizes the risk of accidentally picking up system libraries.
-
-In the current implementation, Spack sets the soname (shared object name) of
-libraries to their install path upon installation. This has two implications:
-
-1. binding does not apply to libraries installed *before* the option was enabled;
-2. toggling the option off does *not* prevent binding of libraries installed when
-   the option was still enabled.
-
-It is also worth noting that:
-
-1. Applications relying on ``dlopen(3)`` will continue to work, even when they open
-   a library by name. This is because ``RPATH``\s are retained in binaries also
-   when ``bind`` is enabled.
-2. ``LD_PRELOAD`` continues to work for the typical use case of overriding
-   symbols, such as preloading a library with a more efficient ``malloc``.
-   However, the preloaded library will be loaded *additionally to*, instead of
-   *in place of* another library with the same name --- this can be problematic
-   in very rare cases where libraries rely on a particular ``init`` or ``fini``
-   order.
-
-.. note::
-
-   In some cases packages provide *stub libraries* that only contain an interface
-   for linking, but lack an implementation for runtime. An example of this is
-   ``libcuda.so``, provided by the CUDA toolkit; it can be used to link against,
-   but the library needed at runtime is the one installed with the CUDA driver.
-   To avoid binding those libraries, they can be marked as non-bindable using
-   a property in the package:
-
-   .. code-block:: python
-
-      class Example(Package):
-         non_bindable_shared_objects = ["libinterface.so"]
-
 ----------------------
 ``terminal_title``
 ----------------------

lib/spack/docs/configuration.rst

@@ -405,19 +405,6 @@ Spack understands several special variables. These are:
 * ``$user``: name of the current user
 * ``$user_cache_path``: user cache directory (``~/.spack`` unless
   :ref:`overridden <local-config-overrides>`)
-* ``$architecture``: the architecture triple of the current host, as
-  detected by Spack.
-* ``$arch``: alias for ``$architecture``.
-* ``$platform``: the platform of the current host, as detected by Spack.
-* ``$operating_system``: the operating system of the current host, as
-  detected by the ``distro`` python module.
-* ``$os``: alias for ``$operating_system``.
-* ``$target``: the ISA target for the current host, as detected by
-  ArchSpec. E.g. ``skylake`` or ``neoverse-n1``.
-* ``$target_family``. The target family for the current host, as
-  detected by ArchSpec. E.g. ``x86_64`` or ``aarch64``.
-* ``$date``: the current date in the format YYYY-MM-DD
-
 
 Note that, as with shell variables, you can write these as ``$varname``
 or with braces to distinguish the variable from surrounding characters:
@@ -562,7 +549,7 @@ down the problem:
 
 You can see above that the ``build_jobs`` and ``debug`` settings are
 built in and are not overridden by a configuration file. The
-``verify_ssl`` setting comes from the ``--insecure`` option on the
+``verify_ssl`` setting comes from the ``--insceure`` option on the
 command line. ``dirty`` and ``install_tree`` come from the custom
 scopes ``./my-scope`` and ``./my-scope-2``, and all other configuration
 options come from the default configuration files that ship with Spack.

lib/spack/docs/containers.rst

@@ -59,7 +59,7 @@ other techniques to minimize the size of the final image:
    &&   echo "  specs:" \
    &&   echo "  - gromacs+mpi" \
    &&   echo "  - mpich" \
-   &&   echo "  concretizer:" \
+   &&   echo "  concretizer: together" \
    &&   echo "    unify: true" \
    &&   echo "  config:" \
    &&   echo "    install_tree: /opt/software" \

lib/spack/docs/contribution_guide.rst

@@ -71,7 +71,7 @@ locally to speed up the review process.
    new release that is causing problems. If this is the case, please file an issue.
 
 
-We currently test against Python 2.7 and 3.6-3.10 on both macOS and Linux and
+We currently test against Python 2.7 and 3.5-3.9 on both macOS and Linux and
 perform 3 types of tests:
 
 .. _cmd-spack-unit-test:
@@ -253,6 +253,27 @@ to update them.
    multiple runs of ``spack style`` just to re-compute line numbers and
    makes it much easier to fix errors directly off of the CI output.
 
+.. warning::
+
+   Flake8 and ``pep8-naming`` require a number of dependencies in order
+   to run.  If you installed ``py-flake8`` and ``py-pep8-naming``, the
+   easiest way to ensure the right packages are on your ``PYTHONPATH`` is
+   to run::
+
+     spack activate py-flake8
+     spack activate pep8-naming
+
+   so that all of the dependencies are symlinked to a central
+   location. If you see an error message like:
+
+   .. code-block:: console
+
+      Traceback (most recent call last):
+        File: "/usr/bin/flake8", line 5, in <module>
+          from pkg_resources import load_entry_point
+      ImportError: No module named pkg_resources
+
+   that means Flake8 couldn't find setuptools in your ``PYTHONPATH``.
 
 ^^^^^^^^^^^^^^^^^^^
 Documentation Tests
@@ -288,9 +309,13 @@ All of these can be installed with Spack, e.g.
 
    .. code-block:: console
 
-      $ spack load py-sphinx py-sphinx-rtd-theme py-sphinxcontrib-programoutput
+      $ spack activate py-sphinx
+      $ spack activate py-sphinx-rtd-theme
+      $ spack activate py-sphinxcontrib-programoutput
 
-   so that all of the dependencies are added to PYTHONPATH.  If you see an error message
+   so that all of the dependencies are symlinked into that Python's
+   tree.  Alternatively, you could arrange for their library
+   directories to be added to PYTHONPATH.  If you see an error message
    like:
 
    .. code-block:: console

lib/spack/docs/developer_guide.rst

@@ -149,9 +149,11 @@ grouped by functionality.
 Package-related modules
 ^^^^^^^^^^^^^^^^^^^^^^^
 
-:mod:`spack.package_base`
-  Contains the :class:`~spack.package_base.PackageBase` class, which
-  is the superclass for all packages in Spack.
+:mod:`spack.package`
+  Contains the :class:`~spack.package_base.Package` class, which
+  is the superclass for all packages in Spack.  Methods on ``Package``
+  implement all phases of the :ref:`package lifecycle
+  <package-lifecycle>` and manage the build process.
 
 :mod:`spack.util.naming`
   Contains functions for mapping between Spack package names,
@@ -963,13 +965,8 @@ completed, the steps to make the point release are:
 
       $ git checkout releases/v0.15
 
-#. If a pull request to the release branch named ``Backports vX.Y.Z`` is not already
-   in the project, create it. This pull request ought to be created as early as
-   possible when working on a release project, so that we can build the release
-   commits incrementally, and identify potential conflicts at an early stage.
-
 #. Cherry-pick each pull request in the ``Done`` column of the release
-   project board onto the ``Backports vX.Y.Z`` pull request.
+   project board onto the release branch.
 
    This is **usually** fairly simple since we squash the commits from the
    vast majority of pull requests. That means there is only one commit
@@ -994,7 +991,7 @@ completed, the steps to make the point release are:
 
       It is important to cherry-pick commits in the order they happened,
       otherwise you can get conflicts while cherry-picking. When
-      cherry-picking look at the merge date,
+      cherry-picking onto a point release, look at the merge date,
       **not** the number of the pull request or the date it was opened.
 
       Sometimes you may **still** get merge conflicts even if you have
@@ -1015,19 +1012,15 @@ completed, the steps to make the point release are:
          branch if neither of the above options makes sense, but this can
          require a lot of work. It's seldom the right choice.
 
-#. When all the commits from the project board are cherry-picked into
-   the ``Backports vX.Y.Z`` pull request, you can push a commit to:
+#. Bump the version in ``lib/spack/spack/__init__.py``.
 
-   1. Bump the version in ``lib/spack/spack/__init__.py``.
-   2. Update ``CHANGELOG.md`` with a list of the changes.
+#. Update ``CHANGELOG.md`` with a list of the changes.
 
    This is typically a summary of the commits you cherry-picked onto the
    release branch. See `the changelog from 0.14.1
    <https://github.com/spack/spack/commit/ff0abb9838121522321df2a054d18e54b566b44a>`_.
 
-#. Merge the ``Backports vX.Y.Z`` PR with the **Rebase and merge** strategy. This
-   is needed to keep track in the release branch of all the commits that were
-   cherry-picked.
+#. Push the release branch to GitHub.
 
 #. Make sure CI passes on the release branch, including:
 
@@ -1046,8 +1039,6 @@ completed, the steps to make the point release are:
 
 #. Follow the steps in :ref:`announcing-releases`.
 
-#. Submit a PR to update the CHANGELOG in the `develop` branch
-   with the addition of this point release.
 
 .. _publishing-releases:
 

lib/spack/docs/environments.rst

@@ -233,8 +233,8 @@ packages will be listed as roots of the Environment.
 
 All of the Spack commands that act on the list of installed specs are
 Environment-sensitive in this way, including ``install``,
-``uninstall``, ``find``, ``extensions``, and more. In the
-:ref:`environment-configuration` section we will discuss
+``uninstall``, ``activate``, ``deactivate``, ``find``, ``extensions``,
+and more. In the :ref:`environment-configuration` section we will discuss
 Environment-sensitive commands further.
 
 ^^^^^^^^^^^^^^^^^^^^^
@@ -376,30 +376,6 @@ from being added again.  At the same time, a spec that already exists in the
 environment, but only as a dependency, will be added to the environment as a
 root spec without the ``--no-add`` option.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Developing Packages in a Spack Environment
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-The ``spack develop`` command allows one to develop Spack packages in
-an environment. It requires a spec containing a concrete version, and
-will configure Spack to install the package from local source. By
-default, it will also clone the package to a subdirectory in the
-environment. This package will have a special variant ``dev_path``
-set, and Spack will ensure the package and its dependents are rebuilt
-any time the environment is installed if the package's local source
-code has been modified. Spack ensures that all instances of a
-developed package in the environment are concretized to match the
-version (and other constraints) passed as the spec argument to the
-``spack develop`` command.
-
-For packages with ``git`` attributes, git branches, tags, and commits can
-also be used as valid concrete versions (see :ref:`version-specifier`).
-This means that for a package ``foo``, ``spack develop foo@git.main`` will clone 
-the ``main`` branch of the package, and ``spack install`` will install from
-that git clone if ``foo`` is in the environment.
-Further development on ``foo`` can be tested by reinstalling the environment,
-and eventually committed and pushed to the upstream git repo.
-
 ^^^^^^^
 Loading
 ^^^^^^^
@@ -478,21 +454,14 @@ them to the Environment.
    spack:
      include:
      - relative/path/to/config.yaml
-     - https://github.com/path/to/raw/config/compilers.yaml
      - /absolute/path/to/packages.yaml
 
-Environments can include files or URLs. File paths can be relative or
-absolute. URLs include the path to the text for individual files or
-can be the path to a directory containing configuration files.
-
-^^^^^^^^^^^^^^^^^^^^^^^^
-Configuration precedence
-^^^^^^^^^^^^^^^^^^^^^^^^
-
-Inline configurations take precedence over included configurations, so
-you don't have to change shared configuration files to make small changes
-to an individual environment. Included configurations listed earlier will
-have higher precedence, as the included configs are applied in reverse order.
+Environments can include files with either relative or absolute
+paths. Inline configurations take precedence over included
+configurations, so you don't have to change shared configuration files
+to make small changes to an individual Environment. Included configs
+listed earlier will have higher precedence, as the included configs are
+applied in reverse order.
 
 -------------------------------
 Manually Editing the Specs List
@@ -519,49 +488,8 @@ available from the yaml file.
 ^^^^^^^^^^^^^^^^^^^
 Spec concretization
 ^^^^^^^^^^^^^^^^^^^
-An environment can be concretized in three different modes and the behavior active under
-any environment is determined by the ``concretizer:unify`` configuration option.
-
-The *default* mode is to unify all specs:
-
-.. code-block:: yaml
-
-   spack:
-       specs:
-         - hdf5+mpi
-         - zlib@1.2.8
-       concretizer:
-         unify: true
-
-This means that any package in the environment corresponds to a single concrete spec. In
-the above example, when ``hdf5`` depends down the line of ``zlib``, it is required to
-take ``zlib@1.2.8`` instead of a newer version. This mode of concretization is
-particularly useful when environment views are used: if every package occurs in
-only one flavor, it is usually possible to merge all install directories into a view.
-
-A downside of unified concretization is that it can be overly strict. For example, a
-concretization error would happen when both ``hdf5+mpi`` and ``hdf5~mpi`` are specified
-in an environment.
-
-The second mode is to *unify when possible*: this makes concretization of root specs
-more independendent. Instead of requiring reuse of dependencies across different root
-specs, it is only maximized:
-
-.. code-block:: yaml
-
-   spack:
-       specs:
-         - hdf5~mpi
-         - hdf5+mpi
-         - zlib@1.2.8
-       concretizer:
-         unify: when_possible
-
-This means that both ``hdf5`` installations will use ``zlib@1.2.8`` as a dependency even
-if newer versions of that library are available.
-
-The third mode of operation is to concretize root specs entirely independently by
-disabling unified concretization:
+An environment can be concretized in three different modes and the behavior active under any environment
+is determined by the ``concretizer:unify`` property. By default specs are concretized *separately*, one after the other:
 
 .. code-block:: yaml
 
@@ -573,11 +501,45 @@ disabling unified concretization:
        concretizer:
          unify: false
 
-In this example ``hdf5`` is concretized separately, and does not consider ``zlib@1.2.8``
-as a constraint or preference. Instead, it will take the latest possible version.
+This mode of operation permits to deploy a full software stack where multiple configurations of the same package
+need to be installed alongside each other using the best possible selection of transitive dependencies. The downside
+is that redundancy of installations is disregarded completely, and thus environments might be more bloated than
+strictly needed. In the example above, for instance, if a version of ``zlib`` newer than ``1.2.8`` is known to Spack,
+then it will be used for both ``hdf5`` installations.
 
-The last two concretization options are typically useful for system administrators and
-user support groups providing a large software stack for their HPC center.
+If redundancy of the environment is a concern, Spack provides a way to install it *together where possible*,
+i.e. trying to maximize reuse of dependencies across different specs:
+
+.. code-block:: yaml
+
+   spack:
+       specs:
+         - hdf5~mpi
+         - hdf5+mpi
+         - zlib@1.2.8
+       concretizer:
+         unify: when_possible
+
+Also in this case Spack allows having multiple configurations of the same package, but privileges the reuse of
+specs over other factors. Going back to our example, this means that both ``hdf5`` installations will use
+``zlib@1.2.8`` as a dependency even if newer versions of that library are available.
+Central installations done at HPC centers by system administrators or user support groups are a common case
+that fits either of these two modes.
+
+Environments can also be configured to concretize all the root specs *together*, in a self-consistent way, to
+ensure that each package in the environment comes with a single configuration:
+
+.. code-block:: yaml
+
+   spack:
+       specs:
+         - hdf5+mpi
+         - zlib@1.2.8
+       concretizer:
+         unify: true
+
+This mode of operation is usually what is required by software developers that want to deploy their development
+environment and have a single view of it in the filesystem.
 
 .. note::
 
@@ -588,10 +550,10 @@ user support groups providing a large software stack for their HPC center.
 
 .. admonition:: Re-concretization of user specs
 
-   When using *unified* concretization (when possible), the entire set of specs will be
+   When concretizing specs *together* or *together where possible* the entire set of specs will be
    re-concretized after any addition of new user specs, to ensure that
-   the environment remains consistent / minimal. When instead unified concretization is
-   disabled, only the new specs will be concretized after any addition.
+   the environment remains consistent / minimal. When instead the specs are concretized
+   separately only the new specs will be re-concretized after any addition.
 
 ^^^^^^^^^^^^^
 Spec Matrices
@@ -630,6 +592,31 @@ The following two Environment manifests are identical:
 Spec matrices can be used to install swaths of software across various
 toolchains.
 
+The concretization logic for spec matrices differs slightly from the
+rest of Spack. If a variant or dependency constraint from a matrix is
+invalid, Spack will reject the constraint and try again without
+it. For example, the following two Environment manifests will produce
+the same specs:
+
+.. code-block:: yaml
+
+   spack:
+     specs:
+       - matrix:
+           - [zlib, libelf, hdf5+mpi]
+           - [^mvapich2@2.2, ^openmpi@3.1.0]
+
+   spack:
+     specs:
+       - zlib
+       - libelf
+       - hdf5+mpi ^mvapich2@2.2
+       - hdf5+mpi ^openmpi@3.1.0
+
+This allows one to create toolchains out of combinations of
+constraints and apply them somewhat indiscriminately to packages,
+without regard for the applicability of the constraint.
+
 ^^^^^^^^^^^^^^^^^^^^
 Spec List References
 ^^^^^^^^^^^^^^^^^^^^
@@ -961,6 +948,9 @@ Variable            Paths
 PATH                bin
 MANPATH             man, share/man
 ACLOCAL_PATH        share/aclocal
+LD_LIBRARY_PATH     lib, lib64
+LIBRARY_PATH        lib, lib64
+CPATH               include
 PKG_CONFIG_PATH     lib/pkgconfig, lib64/pkgconfig, share/pkgconfig
 CMAKE_PREFIX_PATH   .
 =================== =========
@@ -993,7 +983,7 @@ A typical workflow is as follows:
    spack env create -d .
    spack -e . add perl
    spack -e . concretize
-   spack -e . env depfile -o Makefile
+   spack -e . env depfile > Makefile
    make -j64
 
 This generates a ``Makefile`` from a concretized environment in the
@@ -1006,6 +996,7 @@ load, even when packages are built in parallel.
 By default the following phony convenience targets are available:
 
 - ``make all``: installs the environment (default target);
+- ``make fetch-all``: only fetch sources of all packages;
 - ``make clean``: cleans files used by make, but does not uninstall packages.
 
 .. tip::
@@ -1015,17 +1006,8 @@ By default the following phony convenience targets are available:
    printed orderly per package install. To get synchronized output with colors,
    use ``make -j<N> SPACK_COLOR=always --output-sync=recurse``.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Specifying dependencies on generated ``make`` targets
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-An interesting question is how to include generated ``Makefile``\s in your own
-``Makefile``\s. This comes up when you want to install an environment that provides
-executables required in a command for a make target of your own.
-
-The example below shows how to accomplish this: the ``env`` target specifies
-the generated ``spack/env`` target as a prerequisite, meaning that the environment
-gets installed and is available for use in the ``env`` target.
+The following advanced example shows how generated targets can be used in a
+``Makefile``:
 
 .. code:: Makefile
 
@@ -1051,10 +1033,11 @@ gets installed and is available for use in the ``env`` target.
    include env.mk
    endif
 
-This works as follows: when ``make`` is invoked, it first "remakes" the missing
-include ``env.mk`` as there is a target for it. This triggers concretization of
-the environment and makes spack output ``env.mk``. At that point the
-generated target ``spack/env`` becomes available through ``include env.mk``.
+When ``make`` is invoked, it first "remakes" the missing include ``env.mk``
+from its rule, which triggers concretization. When done, the generated target
+``spack/env`` is available. In the above example, the ``env`` target uses this generated
+target as a prerequisite, meaning that it can make use of the installed packages in
+its commands.
 
 As it is typically undesirable to remake ``env.mk`` as part of ``make clean``,
 the include is conditional.
@@ -1065,28 +1048,3 @@ the include is conditional.
    the ``--make-target-prefix`` flag and use the non-phony target
    ``<target-prefix>/env`` as prerequisite, instead of the phony target
    ``<target-prefix>/all``.
-
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Building a subset of the environment
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-The generated ``Makefile``\s contain install targets for each spec, identified
-by ``<name>-<version>-<hash>``. This allows you to install only a subset of the
-packages in the environment. When packages are unique in the environment, it's
-enough to know the name and let tab-completion fill out the version and hash.
-
-The following phony targets are available: ``install/<spec>`` to install the
-spec with its dependencies, and ``install-deps/<spec>`` to *only* install
-its dependencies. This can be useful when certain flags should only apply to
-dependencies. Below we show a use case where a spec is installed with verbose
-output (``spack install --verbose``) while its dependencies are installed silently:
-
-.. code:: console
-
-   $ spack env depfile -o Makefile
-
-   # Install dependencies in parallel, only show a log on error.
-   $ make -j16 install-deps/python-3.11.0-<hash> SPACK_INSTALL_FLAGS=--show-log-on-error
-
-   # Install the root spec with verbose output.
-   $ make -j16 install/python-3.11.0-<hash> SPACK_INSTALL_FLAGS=--verbose

lib/spack/docs/features.rst

@@ -98,42 +98,40 @@ For example, this command:
 
 .. code-block:: console
 
-   $ spack create https://ftp.osuosl.org/pub/blfs/conglomeration/libelf/libelf-0.8.13.tar.gz
+   $ spack create http://www.mr511.de/software/libelf-0.8.13.tar.gz
 
 creates a simple python file:
 
 .. code-block:: python
 
-   from spack.package import *
+   from spack import *
 
 
-   class Libelf(AutotoolsPackage):
+   class Libelf(Package):
        """FIXME: Put a proper description of your package here."""
 
        # FIXME: Add a proper url for your package's homepage here.
-       homepage = "https://www.example.com"
-       url = "https://ftp.osuosl.org/pub/blfs/conglomeration/libelf/libelf-0.8.13.tar.gz"
+       homepage = "http://www.example.com"
+       url      = "http://www.mr511.de/software/libelf-0.8.13.tar.gz"
 
-       # FIXME: Add a list of GitHub accounts to
-       # notify when the package is updated.
-       # maintainers = ["github_user1", "github_user2"]
-
-       version("0.8.13", sha256="591a9b4ec81c1f2042a97aa60564e0cb79d041c52faa7416acb38bc95bd2c76d")
+       version('0.8.13', '4136d7b4c04df68b686570afa26988ac')
 
        # FIXME: Add dependencies if required.
-       # depends_on("foo")
+       # depends_on('foo')
 
-       def configure_args(self):
-           # FIXME: Add arguments other than --prefix
-           # FIXME: If not needed delete this function
-           args = []
-           return args
+       def install(self, spec, prefix):
+           # FIXME: Modify the configure line to suit your build system here.
+           configure('--prefix={0}'.format(prefix))
+
+           # FIXME: Add logic to build and install here.
+           make()
+           make('install')
 
 It doesn't take much python coding to get from there to a working
 package:
 
 .. literalinclude:: _spack_root/var/spack/repos/builtin/packages/libelf/package.py
-   :lines: 5-
+   :lines: 6-
 
 Spack also provides wrapper functions around common commands like
 ``configure``, ``make``, and ``cmake`` to make writing packages

lib/spack/docs/getting_started.rst

@@ -21,39 +21,10 @@ be present on the machine where Spack is run:
    :header-rows: 1
 
 These requirements can be easily installed on most modern Linux systems;
-on macOS, the Command Line Tools package is required, and a full XCode suite 
-may be necessary for some packages such as Qt and apple-gl. Spack is designed
-to run on HPC platforms like Cray.  Not all packages should be expected
-to work on all platforms.
-
-A build matrix showing which packages are working on which systems is shown below.
-
-.. tab-set::
-
-   .. tab-item:: Debian/Ubuntu
-
-      .. code-block:: console
-
-         apt update
-         apt install build-essential ca-certificates coreutils curl environment-modules gfortran git gpg lsb-release python3 python3-distutils python3-venv unzip zip
-
-   .. tab-item:: RHEL
-
-      .. code-block:: console
-
-         yum update -y
-         yum install -y epel-release
-         yum update -y
-         yum --enablerepo epel groupinstall -y "Development Tools"
-         yum --enablerepo epel install -y curl findutils gcc-c++ gcc gcc-gfortran git gnupg2 hostname iproute redhat-lsb-core make patch python3 python3-pip python3-setuptools unzip
-         python3 -m pip install boto3
-
-   .. tab-item:: macOS Brew
-
-      .. code-block:: console
-
-         brew update
-         brew install curl gcc git gnupg zip
+on macOS, XCode is required.  Spack is designed to run on HPC
+platforms like Cray.  Not all packages should be expected
+to work on all platforms.  A build matrix showing which packages are
+working on which systems is planned but not yet available.
 
 ------------
 Installation
@@ -125,41 +96,88 @@ Spack provides two ways of bootstrapping ``clingo``: from pre-built binaries
 (default), or from sources. The fastest way to get started is to bootstrap from
 pre-built binaries.
 
-The first time you concretize a spec, Spack will bootstrap automatically:
+.. note::
+
+   When bootstrapping from pre-built binaries, Spack currently requires 
+   ``patchelf`` on Linux and ``otool`` on macOS. If ``patchelf`` is not in the
+   ``PATH``, Spack will build it from sources, and a C++ compiler is required.
+
+The first time you concretize a spec, Spack will bootstrap in the background:
 
 .. code-block:: console
 
-   $ spack spec zlib
-   ==> Bootstrapping clingo from pre-built binaries
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.4/build_cache/linux-centos7-x86_64-gcc-10.2.1-clingo-bootstrap-spack-ba5ijauisd3uuixtmactc36vps7yfsrl.spec.json
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.4/build_cache/linux-centos7-x86_64/gcc-10.2.1/clingo-bootstrap-spack/linux-centos7-x86_64-gcc-10.2.1-clingo-bootstrap-spack-ba5ijauisd3uuixtmactc36vps7yfsrl.spack
-   ==> Installing "clingo-bootstrap@spack%gcc@10.2.1~docs~ipo+python+static_libstdcpp build_type=Release arch=linux-centos7-x86_64" from a buildcache
-   ==> Bootstrapping patchelf from pre-built binaries
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.4/build_cache/linux-centos7-x86_64-gcc-10.2.1-patchelf-0.16.1-p72zyan5wrzuabtmzq7isa5mzyh6ahdp.spec.json
-   ==> Fetching https://mirror.spack.io/bootstrap/github-actions/v0.4/build_cache/linux-centos7-x86_64/gcc-10.2.1/patchelf-0.16.1/linux-centos7-x86_64-gcc-10.2.1-patchelf-0.16.1-p72zyan5wrzuabtmzq7isa5mzyh6ahdp.spack
-   ==> Installing "patchelf@0.16.1%gcc@10.2.1 ldflags="-static-libstdc++ -static-libgcc"  build_system=autotools arch=linux-centos7-x86_64" from a buildcache
+   $ time spack spec zlib
    Input spec
    --------------------------------
    zlib
 
    Concretized
    --------------------------------
-   zlib@1.2.13%gcc@9.4.0+optimize+pic+shared build_system=makefile arch=linux-ubuntu20.04-icelake
+   zlib@1.2.11%gcc@7.5.0+optimize+pic+shared arch=linux-ubuntu18.04-zen
 
-If for security concerns you cannot bootstrap ``clingo`` from pre-built
-binaries, you have to disable fetching the binaries we generated with Github Actions.
+   real	0m20.023s
+   user	0m18.351s
+   sys	0m0.784s
+
+After this command you'll see that ``clingo`` has been installed for Spack's own use:
 
 .. code-block:: console
 
-   $ spack bootstrap disable github-actions-v0.4
-   ==> "github-actions-v0.4" is now disabled and will not be used for bootstrapping
-   $ spack bootstrap disable github-actions-v0.3
-   ==> "github-actions-v0.3" is now disabled and will not be used for bootstrapping
+   $ spack find -b
+   ==> Showing internal bootstrap store at "/root/.spack/bootstrap/store"
+   ==> 3 installed packages
+   -- linux-rhel5-x86_64 / gcc@9.3.0 -------------------------------
+   clingo-bootstrap@spack  python@3.6
+
+   -- linux-ubuntu18.04-zen / gcc@7.5.0 ----------------------------
+   patchelf@0.13
+
+Subsequent calls to the concretizer will then be much faster:
+
+.. code-block:: console
+
+   $ time spack spec zlib
+   [ ... ]
+   real	0m0.490s
+   user	0m0.431s
+   sys	0m0.041s
+
+
+If for security concerns you cannot bootstrap ``clingo`` from pre-built
+binaries, you have to mark this bootstrapping method as untrusted. This makes
+Spack fall back to bootstrapping from sources:
+
+.. code-block:: console
+
+   $ spack bootstrap untrust github-actions-v0.2
+   ==> "github-actions-v0.2" is now untrusted and will not be used for bootstrapping
 
 You can verify that the new settings are effective with:
 
-.. command-output:: spack bootstrap list
+.. code-block:: console
 
+   $ spack bootstrap list
+   Name: github-actions-v0.2 UNTRUSTED
+
+     Type: buildcache
+
+     Info:
+       url: https://mirror.spack.io/bootstrap/github-actions/v0.2
+       homepage: https://github.com/spack/spack-bootstrap-mirrors
+       releases: https://github.com/spack/spack-bootstrap-mirrors/releases
+
+     Description:
+       Buildcache generated from a public workflow using Github Actions.
+       The sha256 checksum of binaries is checked before installation.
+
+   [ ... ]
+
+   Name: spack-install TRUSTED
+
+     Type: install
+
+     Description:
+       Specs built from sources by Spack. May take a long time.
 
 .. note::
 
@@ -189,7 +207,9 @@ under the ``${HOME}/.spack`` directory. The software installed there can be quer
 
 .. code-block:: console
 
-   $ spack -b find
+   $ spack find --bootstrap
+   ==> Showing internal bootstrap store at "/home/spack/.spack/bootstrap/store"
+   ==> 3 installed packages
    -- linux-ubuntu18.04-x86_64 / gcc@10.1.0 ------------------------
    clingo-bootstrap@spack  python@3.6.9  re2c@1.2.1
 
@@ -198,7 +218,7 @@ In case it's needed the bootstrap store can also be cleaned with:
 .. code-block:: console
 
    $ spack clean -b
-   ==> Removing bootstrapped software and configuration in "/home/spack/.spack/bootstrap"
+   ==> Removing software in "/home/spack/.spack/bootstrap/store"
 
 ^^^^^^^^^^^^^^^^^^
 Check Installation
@@ -1705,11 +1725,9 @@ dependencies or incompatible build tools like autoconf. Here are several
 packages known to work on Windows:
 
 * abseil-cpp
-* bzip2
 * clingo
 * cpuinfo
 * cmake
-* hdf5
 * glm
 * nasm
 * netlib-lapack (requires Intel Fortran)

lib/spack/docs/module_file_support.rst

@@ -77,7 +77,7 @@ installation of a package.
 
    Spack only generates modulefiles when a package is installed. If
    you attempt to install a package and it is already installed, Spack
-   will not regenerate modulefiles for the package. This may lead to
+   will not regenerate modulefiles for the package. This may to
    inconsistent modulefiles if the Spack module configuration has
    changed since the package was installed, either by editing a file
    or changing scopes or environments.
@@ -113,8 +113,6 @@ from language interpreters into their extensions. The latter two instead permit
 fine tune the filesystem layout, content and creation of module files to meet
 site specific conventions.
 
-.. _overide-api-calls-in-package-py:
-
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Override API calls in ``package.py``
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -136,7 +134,7 @@ The second method:
        pass
 
 can instead inject run-time environment modifications in the module files of packages
-that depend on it. In both cases you need to fill ``env`` with the desired
+that depend on it. In both cases you need to fill ``run_env`` with the desired
 list of environment modifications.
 
 .. admonition:: The ``r`` package and callback APIs
@@ -520,33 +518,18 @@ inspections and customize them per-module-set.
     prefix_inspections:
       bin:
         - PATH
-      man:
-        - MANPATH
+      lib:
+        - LIBRARY_PATH
       '':
         - CMAKE_PREFIX_PATH
 
 Prefix inspections are only applied if the relative path inside the
 installation prefix exists. In this case, for a Spack package ``foo``
 installed to ``/spack/prefix/foo``, if ``foo`` installs executables to
-``bin`` but no manpages in ``man``, the generated module file for
+``bin`` but no libraries in ``lib``, the generated module file for
 ``foo`` would update ``PATH`` to contain ``/spack/prefix/foo/bin`` and
 ``CMAKE_PREFIX_PATH`` to contain ``/spack/prefix/foo``, but would not
-update ``MANPATH``.
-
-The default list of environment variables in this config section
-inludes ``PATH``, ``MANPATH``, ``ACLOCAL_PATH``, ``PKG_CONFIG_PATH``
-and ``CMAKE_PREFIX_PATH``, as well as ``DYLD_FALLBACK_LIBRARY_PATH``
-on macOS. On Linux however, the corresponding ``LD_LIBRARY_PATH``
-variable is *not* set, because it affects the behavior of
-system executables too.
-
-.. note::
-
-   In general, the ``LD_LIBRARY_PATH`` variable is not required
-   when using packages built with Spack, thanks to the use of RPATH.
-   Some packages may still need the variable, which is best handled
-   on a per-package basis instead of globally, as explained in
-   :ref:`overide-api-calls-in-package-py`.
+update ``LIBRARY_PATH``.
 
 There is a special case for prefix inspections relative to environment
 views. If all of the following conditions hold for a module set

lib/spack/docs/pipelines.rst

@@ -5,9 +5,9 @@
 
 .. _pipelines:
 
-============
-CI Pipelines
-============
+=========
+Pipelines
+=========
 
 Spack provides commands that support generating and running automated build
 pipelines designed for Gitlab CI.  At the highest level it works like this:
@@ -168,7 +168,7 @@ which specs are up to date and which need to be rebuilt (it's a good idea for ot
 reasons as well, but those are out of scope for this discussion).  In this case we
 have disabled it (using ``rebuild-index: False``) because the index would only be
 generated in the artifacts mirror anyway, and consequently would not be available
-during subsequent pipeline runs.
+during subesequent pipeline runs.
 
 .. note::
    With the addition of reproducible builds (#22887) a previously working
@@ -267,64 +267,24 @@ generated by jobs in the pipeline.
 ``spack ci rebuild``
 ^^^^^^^^^^^^^^^^^^^^^
 
-The purpose of ``spack ci rebuild`` is straightforward: take its assigned
-spec and ensure a binary of a successful build exists on the target mirror.
-If the binary does not already exist, it is built from source and pushed
-to the mirror. The associated stand-alone tests are optionally run against
-the new build. Additionally, files for reproducing the build outside of the
-CI environment are created to facilitate debugging.
+The purpose of the ``spack ci rebuild`` is straightforward: take its assigned
+spec job, check whether the target mirror already has a binary for that spec,
+and if not, build the spec from source and push the binary to the mirror.  To
+accomplish this in a reproducible way, the sub-command prepares a ``spack install``
+command line to build a single spec in the DAG, saves that command in a
+shell script, ``install.sh``, in the current working directory, and then runs
+it to install the spec.  The shell script is also exported as an artifact to
+aid in reproducing the build outside of the CI environment.
 
-If a binary for the spec does not exist on the target mirror, an install
-shell script, ``install.sh``, is created and saved in the current working
-directory. The script is run in a job to install the spec from source. The
-resulting binary package is pushed to the mirror. If ``cdash`` is configured
-for the environment, then the build results will be uploaded to the site.
+If it was necessary to install the spec from source, ``spack ci rebuild`` will
+also subsequently create a binary package for the spec and try to push it to the
+mirror.
 
-Environment variables and values in the ``gitlab-ci`` section of the
-``spack.yaml`` environment file provide inputs to this process. The
-two main sources of environment variables are variables written into
-``.gitlab-ci.yml`` by ``spack ci generate`` and the GitLab CI runtime.
-Several key CI pipeline variables are described in
-:ref:`ci_environment_variables`.
-
-If the ``--tests`` option is provided, stand-alone tests are performed but
-only if the build was successful *and* the package does not appear in the
-list of ``broken-tests-packages``. A shell script, ``test.sh``, is created
-and run to perform the tests. On completion, test logs are exported as job
-artifacts for review and to facilitate debugging. If `cdash` is configured,
-test results are also uploaded to the site.
-
-A snippet from an example ``spack.yaml`` file illustrating use of this
-option *and* specification of a package with broken tests is given below.
-The inclusion of a spec for building ``gptune`` is not shown here. Note
-that ``--tests`` is passed to ``spack ci rebuild`` as part of the
-``gitlab-ci`` script.
-
-.. code-block:: yaml
-
-  gitlab-ci:
-    script:
-      - . "./share/spack/setup-env.sh"
-      - spack --version
-      - cd ${SPACK_CONCRETE_ENV_DIR}
-      - spack env activate --without-view .
-      - spack config add "config:install_tree:projections:${SPACK_JOB_SPEC_PKG_NAME}:'morepadding/{architecture}/{compiler.name}-{compiler.version}/{name}-{version}-{hash}'"
-       - mkdir -p ${SPACK_ARTIFACTS_ROOT}/user_data
-       - if [[ -r /mnt/key/intermediate_ci_signing_key.gpg ]]; then spack gpg trust /mnt/key/intermediate_ci_signing_key.gpg; fi
-       - if [[ -r /mnt/key/spack_public_key.gpg ]]; then spack gpg trust /mnt/key/spack_public_key.gpg; fi
-       - spack -d ci rebuild --tests > >(tee ${SPACK_ARTIFACTS_ROOT}/user_data/pipeline_out.txt) 2> >(tee ${SPACK_ARTIFACTS_ROOT}/user_data/pipeline_err.txt >&2)
-
-     broken-tests-packages:
-       - gptune
-
-In this case, even if ``gptune`` is successfully built from source, the
-pipeline will *not* run its stand-alone tests since the package is listed
-under ``broken-tests-packages``.
-
-Spack's cloud pipelines provide actual, up-to-date examples of the CI/CD
-configuration and environment files used by Spack. You can find them
-under Spack's `stacks
-<https://github.com/spack/spack/tree/develop/share/spack/gitlab/cloud_pipelines/stacks>`_ repository directory.
+The ``spack ci rebuild`` sub-command mainly expects its "input" to come either
+from environment variables or from the ``gitlab-ci`` section of the ``spack.yaml``
+environment file.  There are two main sources of the environment variables, some
+are written into ``.gitlab-ci.yml`` by ``spack ci generate``, and some are
+provided by the GitLab CI runtime.
 
 .. _cmd-spack-ci-rebuild-index:
 
@@ -487,7 +447,7 @@ Note about "no-op" jobs
 ^^^^^^^^^^^^^^^^^^^^^^^
 
 If no specs in an environment need to be rebuilt during a given pipeline run
-(meaning all are already up to date on the mirror), a single successful job
+(meaning all are already up to date on the mirror), a single succesful job
 (a NO-OP) is still generated to avoid an empty pipeline (which GitLab
 considers to be an error).  An optional ``service-job-attributes`` section
 can be added to your ``spack.yaml`` where you can provide ``tags`` and
@@ -765,7 +725,7 @@ above with ``git checkout ${SPACK_CHECKOUT_VERSION}``.
 On the other hand, if you're pointing to a spack repository and branch under your
 control, there may be no benefit in using the captured ``SPACK_CHECKOUT_VERSION``,
 and you can instead just clone using the variables you define (``SPACK_REPO``
-and ``SPACK_REF`` in the example above).
+and ``SPACK_REF`` in the example aboves).
 
 .. _custom_workflow:
 

lib/spack/docs/requirements.txt

@@ -1,12 +1,10 @@
 # These dependencies should be installed using pip in order
 # to build the documentation.
 
-sphinx>=3.4,!=4.1.2,!=5.1.0
+sphinx>=3.4,!=4.1.2
 sphinxcontrib-programoutput
-sphinx-design
 sphinx-rtd-theme
 python-levenshtein
 # Restrict to docutils <0.17 to workaround a list rendering issue in sphinx.
 # https://stackoverflow.com/questions/67542699
 docutils <0.17
-pygments <2.13

lib/spack/docs/spack.yaml

@@ -18,10 +18,7 @@ spack:
   - "py-sphinx@3.4:4.1.1,4.1.3:"
   - py-sphinxcontrib-programoutput
   - py-docutils@:0.16
-  - py-sphinx-design
   - py-sphinx-rtd-theme
-  - py-pygments@:2.12
-
   # VCS
   - git
   - mercurial

lib/spack/docs/tables/system_prerequisites.csv

@@ -1,5 +1,5 @@
 Name, Supported Versions, Notes, Requirement Reason
-Python, 3.6--3.11, , Interpreter for Spack
+Python, 2.7/3.5-3.10, , Interpreter for Spack
 C/C++ Compilers, , , Building software
 make, , , Build software
 patch, , , Build software
@@ -11,7 +11,6 @@ bzip2, , , Compress/Decompress archives
 xz, , , Compress/Decompress archives
 zstd, , Optional, Compress/Decompress archives
 file, , , Create/Use Buildcaches
-lsb-release, , , Linux: identify operating system version
 gnupg2, , , Sign/Verify Buildcaches
 git, , , Manage Software Repositories
 svn, , Optional, Manage Software Repositories

lib/spack/env/cc

@@ -241,28 +241,28 @@ case "$command" in
         mode=cpp
         debug_flags="-g"
         ;;
-    cc|c89|c99|gcc|clang|armclang|icc|icx|pgcc|nvc|xlc|xlc_r|fcc|amdclang|cl.exe|craycc)
+    cc|c89|c99|gcc|clang|armclang|icc|icx|pgcc|nvc|xlc|xlc_r|fcc|amdclang|cl.exe)
         command="$SPACK_CC"
         language="C"
         comp="CC"
         lang_flags=C
         debug_flags="-g"
         ;;
-    c++|CC|g++|clang++|armclang++|icpc|icpx|dpcpp|pgc++|nvc++|xlc++|xlc++_r|FCC|amdclang++|crayCC)
+    c++|CC|g++|clang++|armclang++|icpc|icpx|dpcpp|pgc++|nvc++|xlc++|xlc++_r|FCC|amdclang++)
         command="$SPACK_CXX"
         language="C++"
         comp="CXX"
         lang_flags=CXX
         debug_flags="-g"
         ;;
-    ftn|f90|fc|f95|gfortran|flang|armflang|ifort|ifx|pgfortran|nvfortran|xlf90|xlf90_r|nagfor|frt|amdflang|crayftn)
+    ftn|f90|fc|f95|gfortran|flang|armflang|ifort|ifx|pgfortran|nvfortran|xlf90|xlf90_r|nagfor|frt|amdflang)
         command="$SPACK_FC"
         language="Fortran 90"
         comp="FC"
         lang_flags=F
         debug_flags="-g"
         ;;
-    f77|xlf|xlf_r|pgf77)
+    f77|xlf|xlf_r|pgf77|amdflang)
         command="$SPACK_F77"
         language="Fortran 77"
         comp="F77"
@@ -440,47 +440,6 @@ while [ $# -ne 0 ]; do
         continue
     fi
 
-    if [ -n "${SPACK_COMPILER_FLAGS_KEEP}" ] ; then
-        # NOTE: the eval is required to allow `|` alternatives inside the variable
-        eval "\
-        case \"\$1\" in
-            $SPACK_COMPILER_FLAGS_KEEP)
-                append other_args_list \"\$1\"
-                shift
-                continue
-                ;;
-        esac
-        "
-    fi
-    # the replace list is a space-separated list of pipe-separated pairs,
-    # the first in each pair is the original prefix to be matched, the
-    # second is the replacement prefix
-    if [ -n "${SPACK_COMPILER_FLAGS_REPLACE}" ] ; then
-        for rep in ${SPACK_COMPILER_FLAGS_REPLACE} ; do
-            before=${rep%|*}
-            after=${rep#*|}
-            eval "\
-            stripped=\"\${1##$before}\"
-            "
-            if [ "$stripped" = "$1" ] ; then
-                continue
-            fi
-
-            replaced="$after$stripped" 
-
-            # it matched, remove it
-            shift
-
-            if [ -z "$replaced" ] ; then
-                # completely removed, continue OUTER loop
-                continue 2
-            fi
-
-            # re-build argument list with replacement
-            set -- "$replaced" "$@"
-        done
-    fi
-
     case "$1" in
         -isystem*)
             arg="${1#-isystem}"

lib/spack/env/cce/case-insensitive/crayCC

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

lib/spack/env/cce/craycc

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

lib/spack/env/cce/crayftn

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

lib/spack/external/__init__.py

@@ -18,7 +18,7 @@
 
 * Homepage: https://pypi.python.org/pypi/archspec
 * Usage: Labeling, comparison and detection of microarchitectures
-* Version: 0.2.0 (commit 77640e572725ad97f18e63a04857155752ace045)
+* Version: 0.1.4 (commit b8eea9df2b4204ff27d204452cd46f5199a0b423)
 
 argparse
 --------

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

@@ -132,15 +132,9 @@ def sysctl(*args):
             "model name": sysctl("-n", "machdep.cpu.brand_string"),
         }
     else:
-        model = "unknown"
-        model_str = sysctl("-n", "machdep.cpu.brand_string").lower()
-        if "m2" in model_str:
-            model = "m2"
-        elif "m1" in model_str:
-            model = "m1"
-        elif "apple" in model_str:
-            model = "m1"
-
+        model = (
+            "m1" if "Apple" in sysctl("-n", "machdep.cpu.brand_string") else "unknown"
+        )
         info = {
             "vendor_id": "Apple",
             "flags": [],
@@ -328,26 +322,14 @@ def compatibility_check_for_aarch64(info, target):
     features = set(info.get("Features", "").split())
     vendor = info.get("CPU implementer", "generic")
 
-    # At the moment it's not clear how to detect compatibility with
-    # a specific version of the architecture
-    if target.vendor == "generic" and target.name != "aarch64":
-        return False
-
     arch_root = TARGETS[basename]
-    arch_root_and_vendor = arch_root == target.family and target.vendor in (
-        vendor,
-        "generic",
+    return (
+        (target == arch_root or arch_root in target.ancestors)
+        and target.vendor in (vendor, "generic")
+        # On macOS it seems impossible to get all the CPU features with syctl info
+        and (target.features.issubset(features) or platform.system() == "Darwin")
     )
 
-    # On macOS it seems impossible to get all the CPU features
-    # with syctl info, but for ARM we can get the exact model
-    if platform.system() == "Darwin":
-        model_key = info.get("model", basename)
-        model = TARGETS[model_key]
-        return arch_root_and_vendor and (target == model or target in model.ancestors)
-
-    return arch_root_and_vendor and target.features.issubset(features)
-
 
 @compatibility_check(architecture_family="riscv64")
 def compatibility_check_for_riscv64(info, target):

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

@@ -106,7 +106,7 @@ def __eq__(self, other):
             self.name == other.name
             and self.vendor == other.vendor
             and self.features == other.features
-            and self.parents == other.parents  # avoid ancestors here
+            and self.ancestors == other.ancestors
             and self.compilers == other.compilers
             and self.generation == other.generation
         )

lib/spack/external/archspec/json/cpu/microarchitectures.json

@@ -85,7 +85,7 @@
         "intel": [
           {
             "versions": ":",
-            "name": "pentium4",
+            "name": "x86-64",
             "flags": "-march={name} -mtune=generic"
           }
         ],
@@ -1099,7 +1099,8 @@
         "avx512cd",
         "avx512vbmi",
         "avx512ifma",
-        "sha"
+        "sha",
+        "umip"
       ],
       "compilers": {
         "gcc": [
@@ -1262,6 +1263,7 @@
         "avx512vbmi",
         "avx512ifma",
         "sha_ni",
+        "umip",
         "clwb",
         "rdpid",
         "gfni",
@@ -2093,163 +2095,8 @@
         ]
       }
     },
-    "armv8.1a": {
-      "from": ["aarch64"],
-      "vendor": "generic",
-      "features": [],
-      "compilers": {
-        "gcc": [
-          {
-            "versions": "5:",
-            "flags": "-march=armv8.1-a -mtune=generic"
-          }
-        ],
-        "clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.1-a -mtune=generic"
-          }
-        ],
-        "apple-clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.1-a -mtune=generic"
-          }
-        ],
-        "arm": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.1-a -mtune=generic"
-          }
-        ]
-      }
-    },
-    "armv8.2a": {
-      "from": ["armv8.1a"],
-      "vendor": "generic",
-      "features": [],
-      "compilers": {
-        "gcc": [
-          {
-            "versions": "6:",
-            "flags": "-march=armv8.2-a -mtune=generic"
-          }
-        ],
-        "clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.2-a -mtune=generic"
-          }
-        ],
-        "apple-clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.2-a -mtune=generic"
-          }
-        ],
-        "arm": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.2-a -mtune=generic"
-          }
-        ]
-      }
-    },
-    "armv8.3a": {
-      "from": ["armv8.2a"],
-      "vendor": "generic",
-      "features": [],
-      "compilers": {
-        "gcc": [
-          {
-            "versions": "6:",
-            "flags": "-march=armv8.3-a -mtune=generic"
-          }
-        ],
-        "clang": [
-          {
-            "versions": "6:",
-            "flags": "-march=armv8.3-a -mtune=generic"
-          }
-        ],
-        "apple-clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.3-a -mtune=generic"
-          }
-        ],
-        "arm": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.3-a -mtune=generic"
-          }
-        ]
-      }
-    },
-    "armv8.4a": {
-      "from": ["armv8.3a"],
-      "vendor": "generic",
-      "features": [],
-      "compilers": {
-        "gcc": [
-          {
-            "versions": "8:",
-            "flags": "-march=armv8.4-a -mtune=generic"
-          }
-        ],
-        "clang": [
-          {
-            "versions": "8:",
-            "flags": "-march=armv8.4-a -mtune=generic"
-          }
-        ],
-        "apple-clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.4-a -mtune=generic"
-          }
-        ],
-        "arm": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.4-a -mtune=generic"
-          }
-        ]
-      }
-    },
-    "armv8.5a": {
-      "from": ["armv8.4a"],
-      "vendor": "generic",
-      "features": [],
-      "compilers": {
-        "gcc": [
-          {
-            "versions": "9:",
-            "flags": "-march=armv8.5-a -mtune=generic"
-          }
-        ],
-        "clang": [
-          {
-            "versions": "11:",
-            "flags": "-march=armv8.5-a -mtune=generic"
-          }
-        ],
-        "apple-clang": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.5-a -mtune=generic"
-          }
-        ],
-        "arm": [
-          {
-            "versions": ":",
-            "flags": "-march=armv8.5-a -mtune=generic"
-          }
-        ]
-      }
-    },
     "thunderx2": {
-      "from": ["armv8.1a"],
+      "from": ["aarch64"],
       "vendor": "Cavium",
       "features": [
         "fp",
@@ -2296,7 +2143,7 @@
       }
     },
     "a64fx": {
-      "from": ["armv8.2a"],
+      "from": ["aarch64"],
       "vendor": "Fujitsu",
       "features": [
         "fp",
@@ -2364,7 +2211,7 @@
         ]
       }
     },
-    "cortex_a72": {
+    "graviton": {
       "from": ["aarch64"],
       "vendor": "ARM",
       "features": [
@@ -2390,19 +2237,19 @@
               },
               {
                   "versions": "6:",
-                  "flags" : "-mcpu=cortex-a72"
+                  "flags" : "-march=armv8-a+crc+crypto -mtune=cortex-a72"
               }
           ],
           "clang" : [
               {
                   "versions": "3.9:",
-                  "flags" : "-mcpu=cortex-a72"
+                  "flags" : "-march=armv8-a+crc+crypto"
               }
           ]
       }
     },
-    "neoverse_n1": {
-      "from": ["cortex_a72", "armv8.2a"],
+    "graviton2": {
+      "from": ["aarch64"],
       "vendor": "ARM",
       "features": [
           "fp",
@@ -2451,7 +2298,7 @@
               },
               {
                   "versions": "9.0:",
-                  "flags" : "-mcpu=neoverse-n1"
+                  "flags" : "-march=armv8.2-a+fp16+rcpc+dotprod+crypto -mtune=neoverse-n1"
               }
           ],
           "clang" : [
@@ -2462,10 +2309,6 @@
               {
                   "versions": "5:",
                   "flags" : "-march=armv8.2-a+fp16+rcpc+dotprod+crypto"
-              },
-              {
-                  "versions": "10:",
-                  "flags" : "-mcpu=neoverse-n1"
               }
           ],
           "arm" : [
@@ -2476,113 +2319,8 @@
           ]
       }
     },
-    "neoverse_v1": {
-      "from": ["neoverse_n1", "armv8.4a"],
-      "vendor": "ARM",
-      "features": [
-          "fp",
-          "asimd",
-          "evtstrm",
-          "aes",
-          "pmull",
-          "sha1",
-          "sha2",
-          "crc32",
-          "atomics",
-          "fphp",
-          "asimdhp",
-          "cpuid",
-          "asimdrdm",
-          "jscvt",
-          "fcma",
-          "lrcpc",
-          "dcpop",
-          "sha3",
-          "sm3",
-          "sm4",
-          "asimddp",
-          "sha512",
-          "sve",
-          "asimdfhm",
-          "dit",
-          "uscat",
-          "ilrcpc",
-          "flagm",
-          "ssbs",
-          "paca",
-          "pacg",
-          "dcpodp",
-          "svei8mm",
-          "svebf16",
-          "i8mm",
-          "bf16",
-          "dgh",
-          "rng"
-      ],
-      "compilers" : {
-          "gcc": [
-              {
-                  "versions": "4.8:4.8.9",
-                  "flags": "-march=armv8-a"
-              },
-              {
-                  "versions": "4.9:5.9",
-                  "flags": "-march=armv8-a+crc+crypto"
-              },
-              {
-                  "versions": "6:6.9",
-                  "flags" : "-march=armv8.1-a"
-              },
-              {
-                  "versions": "7:7.9",
-                  "flags" : "-march=armv8.2-a+crypto+fp16 -mtune=cortex-a72"
-              },
-              {
-                  "versions": "8.0:8.9",
-                  "flags" : "-march=armv8.2-a+fp16+dotprod+crypto -mtune=cortex-a72"
-              },
-              {
-                  "versions": "9.0:9.9",
-                  "flags" : "-mcpu=neoverse-v1"
-              },
-	            {
-                  "versions": "10.0:",
-                  "flags" : "-mcpu=neoverse-v1"
-              }
-
-          ],
-          "clang" : [
-              {
-                  "versions": "3.9:4.9",
-                  "flags" : "-march=armv8.2-a+fp16+crc+crypto"
-              },
-              {
-                  "versions": "5:10",
-                  "flags" : "-march=armv8.2-a+fp16+rcpc+dotprod+crypto"
-              },
-              {
-                  "versions": "11:",
-                  "flags" : "-march=armv8.4-a+sve+ssbs+fp16+bf16+crypto+i8mm+rng"
-              },
-              {
-                  "versions": "12:",
-                  "flags" : "-mcpu=neoverse-v1"
-              }
-          ],
-          "arm" : [
-              {
-                  "versions": "20:21.9",
-                  "flags" : "-march=armv8.2-a+sve+fp16+rcpc+dotprod+crypto"
-              },
-	            {
-                  "versions": "22:",
-                  "flags" : "-march=armv8.4-a+sve+ssbs+fp16+bf16+crypto+i8mm+rng"
-              }
-          ]
-      }
-    },
     "m1": {
-      "from": ["armv8.4a"],
+      "from": ["aarch64"],
       "vendor": "Apple",
       "features": [
           "fp",
@@ -2647,76 +2385,6 @@
         ]
       }
     },
-    "m2": {
-      "from": ["m1", "armv8.5a"],
-      "vendor": "Apple",
-      "features": [
-          "fp",
-          "asimd",
-          "evtstrm",
-          "aes",
-          "pmull",
-          "sha1",
-          "sha2",
-          "crc32",
-          "atomics",
-          "fphp",
-          "asimdhp",
-          "cpuid",
-          "asimdrdm",
-          "jscvt",
-          "fcma",
-          "lrcpc",
-          "dcpop",
-          "sha3",
-          "asimddp",
-          "sha512",
-          "asimdfhm",
-          "dit",
-          "uscat",
-          "ilrcpc",
-          "flagm",
-          "ssbs",
-          "sb",
-          "paca",
-          "pacg",
-          "dcpodp",
-          "flagm2",
-          "frint",
-          "ecv",
-          "bf16",
-          "i8mm",
-          "bti"
-      ],
-      "compilers": {
-        "gcc": [
-          {
-            "versions": "8.0:",
-            "flags" : "-march=armv8.5-a -mtune=generic"
-          }
-        ],
-        "clang" : [
-          {
-            "versions": "9.0:12.0",
-            "flags" : "-march=armv8.5-a"
-          },
-          {
-            "versions": "13.0:",
-            "flags" : "-mcpu=apple-m1"
-          }
-        ],
-        "apple-clang": [
-          {
-            "versions": "11.0:12.5",
-            "flags" : "-march=armv8.5-a"
-          },
-          {
-            "versions": "13.0:",
-            "flags" : "-mcpu=vortex"
-          }
-        ]
-      }
-    },
     "arm": {
       "from": [],
       "vendor": "generic",

lib/spack/external/ctest_log_parser.py

@@ -71,12 +71,11 @@
 import re
 import math
 import multiprocessing
-import io
-import sys
-import threading
 import time
 from contextlib import contextmanager
 
+from six import StringIO
+from six import string_types
 
 _error_matches = [
     "^FAIL: ",
@@ -245,7 +244,7 @@ def __getitem__(self, line_no):
 
     def __str__(self):
         """Returns event lines and context."""
-        out = io.StringIO()
+        out = StringIO()
         for i in range(self.start, self.end):
             if i == self.line_no:
                 out.write('  >> %-6d%s' % (i, self[i]))
@@ -385,7 +384,7 @@ def parse(self, stream, context=6, jobs=None):
             (tuple): two lists containing ``BuildError`` and
                 ``BuildWarning`` objects.
         """
-        if isinstance(stream, str):
+        if isinstance(stream, string_types):
             with open(stream) as f:
                 return self.parse(f, context, jobs)
 
@@ -410,12 +409,7 @@ def parse(self, stream, context=6, jobs=None):
             pool = multiprocessing.Pool(jobs)
             try:
                 # this is a workaround for a Python bug in Pool with ctrl-C
-                if sys.version_info >= (3, 2):
-                    max_timeout = threading.TIMEOUT_MAX
-                else:
-                    max_timeout = 9999999
-                results = pool.map_async(_parse_unpack, args, 1).get(max_timeout)
-
+                results = pool.map_async(_parse_unpack, args, 1).get(9999999)
                 errors, warnings, timings = zip(*results)
             finally:
                 pool.terminate()

lib/spack/external/py2/functools32/LICENSE

@@ -0,0 +1,289 @@
+A. HISTORY OF THE SOFTWARE
+==========================
+
+Python was created in the early 1990s by Guido van Rossum at Stichting
+Mathematisch Centrum (CWI, see http://www.cwi.nl) in the Netherlands
+as a successor of a language called ABC.  Guido remains Python's
+principal author, although it includes many contributions from others.
+
+In 1995, Guido continued his work on Python at the Corporation for
+National Research Initiatives (CNRI, see http://www.cnri.reston.va.us)
+in Reston, Virginia where he released several versions of the
+software.
+
+In May 2000, Guido and the Python core development team moved to
+BeOpen.com to form the BeOpen PythonLabs team.  In October of the same
+year, the PythonLabs team moved to Digital Creations (now Zope
+Corporation, see http://www.zope.com).  In 2001, the Python Software
+Foundation (PSF, see http://www.python.org/psf/) was formed, a
+non-profit organization created specifically to own Python-related
+Intellectual Property.  Zope Corporation is a sponsoring member of
+the PSF.
+
+All Python releases are Open Source (see http://www.opensource.org for
+the Open Source Definition).  Historically, most, but not all, Python
+releases have also been GPL-compatible; the table below summarizes
+the various releases.
+
+    Release         Derived     Year        Owner       GPL-
+                    from                                compatible? (1)
+
+    0.9.0 thru 1.2              1991-1995   CWI         yes
+    1.3 thru 1.5.2  1.2         1995-1999   CNRI        yes
+    1.6             1.5.2       2000        CNRI        no
+    2.0             1.6         2000        BeOpen.com  no
+    1.6.1           1.6         2001        CNRI        yes (2)
+    2.1             2.0+1.6.1   2001        PSF         no
+    2.0.1           2.0+1.6.1   2001        PSF         yes
+    2.1.1           2.1+2.0.1   2001        PSF         yes
+    2.2             2.1.1       2001        PSF         yes
+    2.1.2           2.1.1       2002        PSF         yes
+    2.1.3           2.1.2       2002        PSF         yes
+    2.2.1           2.2         2002        PSF         yes
+    2.2.2           2.2.1       2002        PSF         yes
+    2.2.3           2.2.2       2003        PSF         yes
+    2.3             2.2.2       2002-2003   PSF         yes
+    2.3.1           2.3         2002-2003   PSF         yes
+    2.3.2           2.3.1       2002-2003   PSF         yes
+    2.3.3           2.3.2       2002-2003   PSF         yes
+    2.3.4           2.3.3       2004        PSF         yes
+    2.3.5           2.3.4       2005        PSF         yes
+    2.4             2.3         2004        PSF         yes
+    2.4.1           2.4         2005        PSF         yes
+    2.4.2           2.4.1       2005        PSF         yes
+    2.4.3           2.4.2       2006        PSF         yes
+    2.4.4           2.4.3       2006        PSF         yes
+    2.5             2.4         2006        PSF         yes
+    2.5.1           2.5         2007        PSF         yes
+    2.5.2           2.5.1       2008        PSF         yes
+    2.5.3           2.5.2       2008        PSF         yes
+    2.6             2.5         2008        PSF         yes
+    2.6.1           2.6         2008        PSF         yes
+    2.6.2           2.6.1       2009        PSF         yes
+    2.6.3           2.6.2       2009        PSF         yes
+    2.6.4           2.6.3       2009        PSF         yes
+    2.6.5           2.6.4       2010        PSF         yes
+    3.0             2.6         2008        PSF         yes
+    3.0.1           3.0         2009        PSF         yes
+    3.1             3.0.1       2009        PSF         yes
+    3.1.1           3.1         2009        PSF         yes
+    3.1.2           3.1.1       2010        PSF         yes
+    3.1.3           3.1.2       2010        PSF         yes
+    3.1.4           3.1.3       2011        PSF         yes
+    3.2             3.1         2011        PSF         yes
+    3.2.1           3.2         2011        PSF         yes
+    3.2.2           3.2.1       2011        PSF         yes
+    3.2.3           3.2.2       2012        PSF         yes
+
+Footnotes:
+
+(1) GPL-compatible doesn't mean that we're distributing Python under
+    the GPL.  All Python licenses, unlike the GPL, let you distribute
+    a modified version without making your changes open source.  The
+    GPL-compatible licenses make it possible to combine Python with
+    other software that is released under the GPL; the others don't.
+
+(2) According to Richard Stallman, 1.6.1 is not GPL-compatible,
+    because its license has a choice of law clause.  According to
+    CNRI, however, Stallman's lawyer has told CNRI's lawyer that 1.6.1
+    is "not incompatible" with the GPL.
+
+Thanks to the many outside volunteers who have worked under Guido's
+direction to make these releases possible.
+
+
+B. TERMS AND CONDITIONS FOR ACCESSING OR OTHERWISE USING PYTHON
+===============================================================
+
+PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
+--------------------------------------------
+
+1. This LICENSE AGREEMENT is between the Python Software Foundation
+("PSF"), and the Individual or Organization ("Licensee") accessing and
+otherwise using this software ("Python") in source or binary form and
+its associated documentation.
+
+2. Subject to the terms and conditions of this License Agreement, PSF hereby
+grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
+analyze, test, perform and/or display publicly, prepare derivative works,
+distribute, and otherwise use Python alone or in any derivative version,
+provided, however, that PSF's License Agreement and PSF's notice of copyright,
+i.e., "Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+2011, 2012 Python Software Foundation; All Rights Reserved" are retained in Python
+alone or in any derivative version prepared by Licensee.
+
+3. In the event Licensee prepares a derivative work that is based on
+or incorporates Python or any part thereof, and wants to make
+the derivative work available to others as provided herein, then
+Licensee hereby agrees to include in any such work a brief summary of
+the changes made to Python.
+
+4. PSF is making Python available to Licensee on an "AS IS"
+basis.  PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON,
+OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+6. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+7. Nothing in this License Agreement shall be deemed to create any
+relationship of agency, partnership, or joint venture between PSF and
+Licensee.  This License Agreement does not grant permission to use PSF
+trademarks or trade name in a trademark sense to endorse or promote
+products or services of Licensee, or any third party.
+
+8. By copying, installing or otherwise using Python, Licensee
+agrees to be bound by the terms and conditions of this License
+Agreement.
+
+
+BEOPEN.COM LICENSE AGREEMENT FOR PYTHON 2.0
+-------------------------------------------
+
+BEOPEN PYTHON OPEN SOURCE LICENSE AGREEMENT VERSION 1
+
+1. This LICENSE AGREEMENT is between BeOpen.com ("BeOpen"), having an
+office at 160 Saratoga Avenue, Santa Clara, CA 95051, and the
+Individual or Organization ("Licensee") accessing and otherwise using
+this software in source or binary form and its associated
+documentation ("the Software").
+
+2. Subject to the terms and conditions of this BeOpen Python License
+Agreement, BeOpen hereby grants Licensee a non-exclusive,
+royalty-free, world-wide license to reproduce, analyze, test, perform
+and/or display publicly, prepare derivative works, distribute, and
+otherwise use the Software alone or in any derivative version,
+provided, however, that the BeOpen Python License is retained in the
+Software, alone or in any derivative version prepared by Licensee.
+
+3. BeOpen is making the Software available to Licensee on an "AS IS"
+basis.  BEOPEN MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, BEOPEN MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF THE SOFTWARE WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+4. BEOPEN SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF THE
+SOFTWARE FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS
+AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THE SOFTWARE, OR ANY
+DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+5. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+6. This License Agreement shall be governed by and interpreted in all
+respects by the law of the State of California, excluding conflict of
+law provisions.  Nothing in this License Agreement shall be deemed to
+create any relationship of agency, partnership, or joint venture
+between BeOpen and Licensee.  This License Agreement does not grant
+permission to use BeOpen trademarks or trade names in a trademark
+sense to endorse or promote products or services of Licensee, or any
+third party.  As an exception, the "BeOpen Python" logos available at
+http://www.pythonlabs.com/logos.html may be used according to the
+permissions granted on that web page.
+
+7. By copying, installing or otherwise using the software, Licensee
+agrees to be bound by the terms and conditions of this License
+Agreement.
+
+
+CNRI LICENSE AGREEMENT FOR PYTHON 1.6.1
+---------------------------------------
+
+1. This LICENSE AGREEMENT is between the Corporation for National
+Research Initiatives, having an office at 1895 Preston White Drive,
+Reston, VA 20191 ("CNRI"), and the Individual or Organization
+("Licensee") accessing and otherwise using Python 1.6.1 software in
+source or binary form and its associated documentation.
+
+2. Subject to the terms and conditions of this License Agreement, CNRI
+hereby grants Licensee a nonexclusive, royalty-free, world-wide
+license to reproduce, analyze, test, perform and/or display publicly,
+prepare derivative works, distribute, and otherwise use Python 1.6.1
+alone or in any derivative version, provided, however, that CNRI's
+License Agreement and CNRI's notice of copyright, i.e., "Copyright (c)
+1995-2001 Corporation for National Research Initiatives; All Rights
+Reserved" are retained in Python 1.6.1 alone or in any derivative
+version prepared by Licensee.  Alternately, in lieu of CNRI's License
+Agreement, Licensee may substitute the following text (omitting the
+quotes): "Python 1.6.1 is made available subject to the terms and
+conditions in CNRI's License Agreement.  This Agreement together with
+Python 1.6.1 may be located on the Internet using the following
+unique, persistent identifier (known as a handle): 1895.22/1013.  This
+Agreement may also be obtained from a proxy server on the Internet
+using the following URL: http://hdl.handle.net/1895.22/1013".
+
+3. In the event Licensee prepares a derivative work that is based on
+or incorporates Python 1.6.1 or any part thereof, and wants to make
+the derivative work available to others as provided herein, then
+Licensee hereby agrees to include in any such work a brief summary of
+the changes made to Python 1.6.1.
+
+4. CNRI is making Python 1.6.1 available to Licensee on an "AS IS"
+basis.  CNRI MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, CNRI MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON 1.6.1 WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+5. CNRI SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+1.6.1 FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 1.6.1,
+OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+6. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+7. This License Agreement shall be governed by the federal
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+limitation the federal copyright law, and, to the extent such
+U.S. federal law does not apply, by the law of the Commonwealth of
+Virginia, excluding Virginia's conflict of law provisions.
+Notwithstanding the foregoing, with regard to derivative works based
+on Python 1.6.1 that incorporate non-separable material that was
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+
+        ACCEPT
+
+
+CWI LICENSE AGREEMENT FOR PYTHON 0.9.0 THROUGH 1.2
+--------------------------------------------------
+
+Copyright (c) 1991 - 1995, Stichting Mathematisch Centrum Amsterdam,
+The Netherlands.  All rights reserved.
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
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+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
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+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

lib/spack/external/py2/functools32/__init__.py

@@ -0,0 +1 @@
+from .functools32 import *

lib/spack/external/py2/functools32/_dummy_thread32.py

@@ -0,0 +1,158 @@
+"""Drop-in replacement for the thread module.
+
+Meant to be used as a brain-dead substitute so that threaded code does
+not need to be rewritten for when the thread module is not present.
+
+Suggested usage is::
+
+    try:
+        try:
+            import _thread  # Python >= 3
+        except:
+            import thread as _thread  # Python < 3
+    except ImportError:
+        import _dummy_thread as _thread
+
+"""
+# Exports only things specified by thread documentation;
+# skipping obsolete synonyms allocate(), start_new(), exit_thread().
+__all__ = ['error', 'start_new_thread', 'exit', 'get_ident', 'allocate_lock',
+           'interrupt_main', 'LockType']
+
+# A dummy value
+TIMEOUT_MAX = 2**31
+
+# NOTE: this module can be imported early in the extension building process,
+# and so top level imports of other modules should be avoided.  Instead, all
+# imports are done when needed on a function-by-function basis.  Since threads
+# are disabled, the import lock should not be an issue anyway (??).
+
+class error(Exception):
+    """Dummy implementation of _thread.error."""
+
+    def __init__(self, *args):
+        self.args = args
+
+def start_new_thread(function, args, kwargs={}):
+    """Dummy implementation of _thread.start_new_thread().
+
+    Compatibility is maintained by making sure that ``args`` is a
+    tuple and ``kwargs`` is a dictionary.  If an exception is raised
+    and it is SystemExit (which can be done by _thread.exit()) it is
+    caught and nothing is done; all other exceptions are printed out
+    by using traceback.print_exc().
+
+    If the executed function calls interrupt_main the KeyboardInterrupt will be
+    raised when the function returns.
+
+    """
+    if type(args) != type(tuple()):
+        raise TypeError("2nd arg must be a tuple")
+    if type(kwargs) != type(dict()):
+        raise TypeError("3rd arg must be a dict")
+    global _main
+    _main = False
+    try:
+        function(*args, **kwargs)
+    except SystemExit:
+        pass
+    except:
+        import traceback
+        traceback.print_exc()
+    _main = True
+    global _interrupt
+    if _interrupt:
+        _interrupt = False
+        raise KeyboardInterrupt
+
+def exit():
+    """Dummy implementation of _thread.exit()."""
+    raise SystemExit
+
+def get_ident():
+    """Dummy implementation of _thread.get_ident().
+
+    Since this module should only be used when _threadmodule is not
+    available, it is safe to assume that the current process is the
+    only thread.  Thus a constant can be safely returned.
+    """
+    return -1
+
+def allocate_lock():
+    """Dummy implementation of _thread.allocate_lock()."""
+    return LockType()
+
+def stack_size(size=None):
+    """Dummy implementation of _thread.stack_size()."""
+    if size is not None:
+        raise error("setting thread stack size not supported")
+    return 0
+
+class LockType(object):
+    """Class implementing dummy implementation of _thread.LockType.
+
+    Compatibility is maintained by maintaining self.locked_status
+    which is a boolean that stores the state of the lock.  Pickling of
+    the lock, though, should not be done since if the _thread module is
+    then used with an unpickled ``lock()`` from here problems could
+    occur from this class not having atomic methods.
+
+    """
+
+    def __init__(self):
+        self.locked_status = False
+
+    def acquire(self, waitflag=None, timeout=-1):
+        """Dummy implementation of acquire().
+
+        For blocking calls, self.locked_status is automatically set to
+        True and returned appropriately based on value of
+        ``waitflag``.  If it is non-blocking, then the value is
+        actually checked and not set if it is already acquired.  This
+        is all done so that threading.Condition's assert statements
+        aren't triggered and throw a little fit.
+
+        """
+        if waitflag is None or waitflag:
+            self.locked_status = True
+            return True
+        else:
+            if not self.locked_status:
+                self.locked_status = True
+                return True
+            else:
+                if timeout > 0:
+                    import time
+                    time.sleep(timeout)
+                return False
+
+    __enter__ = acquire
+
+    def __exit__(self, typ, val, tb):
+        self.release()
+
+    def release(self):
+        """Release the dummy lock."""
+        # XXX Perhaps shouldn't actually bother to test?  Could lead
+        #     to problems for complex, threaded code.
+        if not self.locked_status:
+            raise error
+        self.locked_status = False
+        return True
+
+    def locked(self):
+        return self.locked_status
+
+# Used to signal that interrupt_main was called in a "thread"
+_interrupt = False
+# True when not executing in a "thread"
+_main = True
+
+def interrupt_main():
+    """Set _interrupt flag to True to have start_new_thread raise
+    KeyboardInterrupt upon exiting."""
+    if _main:
+        raise KeyboardInterrupt
+    else:
+        global _interrupt
+        _interrupt = True

lib/spack/external/py2/functools32/functools32.py

@@ -0,0 +1,423 @@
+"""functools.py - Tools for working with functions and callable objects
+"""
+# Python module wrapper for _functools C module
+# to allow utilities written in Python to be added
+# to the functools module.
+# Written by Nick Coghlan <ncoghlan at gmail.com>
+# and Raymond Hettinger <python at rcn.com>
+#   Copyright (C) 2006-2010 Python Software Foundation.
+# See C source code for _functools credits/copyright
+
+__all__ = ['update_wrapper', 'wraps', 'WRAPPER_ASSIGNMENTS', 'WRAPPER_UPDATES',
+           'total_ordering', 'cmp_to_key', 'lru_cache', 'reduce', 'partial']
+
+from _functools import partial, reduce
+from collections import MutableMapping, namedtuple
+from .reprlib32 import recursive_repr as _recursive_repr
+from weakref import proxy as _proxy
+import sys as _sys
+try:
+    from thread import allocate_lock as Lock
+except ImportError:
+    from ._dummy_thread32 import allocate_lock as Lock
+
+################################################################################
+### OrderedDict
+################################################################################
+
+class _Link(object):
+    __slots__ = 'prev', 'next', 'key', '__weakref__'
+
+class OrderedDict(dict):
+    'Dictionary that remembers insertion order'
+    # An inherited dict maps keys to values.
+    # The inherited dict provides __getitem__, __len__, __contains__, and get.
+    # The remaining methods are order-aware.
+    # Big-O running times for all methods are the same as regular dictionaries.
+
+    # The internal self.__map dict maps keys to links in a doubly linked list.
+    # The circular doubly linked list starts and ends with a sentinel element.
+    # The sentinel element never gets deleted (this simplifies the algorithm).
+    # The sentinel is in self.__hardroot with a weakref proxy in self.__root.
+    # The prev links are weakref proxies (to prevent circular references).
+    # Individual links are kept alive by the hard reference in self.__map.
+    # Those hard references disappear when a key is deleted from an OrderedDict.
+
+    def __init__(self, *args, **kwds):
+        '''Initialize an ordered dictionary.  The signature is the same as
+        regular dictionaries, but keyword arguments are not recommended because
+        their insertion order is arbitrary.
+
+        '''
+        if len(args) > 1:
+            raise TypeError('expected at most 1 arguments, got %d' % len(args))
+        try:
+            self.__root
+        except AttributeError:
+            self.__hardroot = _Link()
+            self.__root = root = _proxy(self.__hardroot)
+            root.prev = root.next = root
+            self.__map = {}
+        self.__update(*args, **kwds)
+
+    def __setitem__(self, key, value,
+                    dict_setitem=dict.__setitem__, proxy=_proxy, Link=_Link):
+        'od.__setitem__(i, y) <==> od[i]=y'
+        # Setting a new item creates a new link at the end of the linked list,
+        # and the inherited dictionary is updated with the new key/value pair.
+        if key not in self:
+            self.__map[key] = link = Link()
+            root = self.__root
+            last = root.prev
+            link.prev, link.next, link.key = last, root, key
+            last.next = link
+            root.prev = proxy(link)
+        dict_setitem(self, key, value)
+
+    def __delitem__(self, key, dict_delitem=dict.__delitem__):
+        'od.__delitem__(y) <==> del od[y]'
+        # Deleting an existing item uses self.__map to find the link which gets
+        # removed by updating the links in the predecessor and successor nodes.
+        dict_delitem(self, key)
+        link = self.__map.pop(key)
+        link_prev = link.prev
+        link_next = link.next
+        link_prev.next = link_next
+        link_next.prev = link_prev
+
+    def __iter__(self):
+        'od.__iter__() <==> iter(od)'
+        # Traverse the linked list in order.
+        root = self.__root
+        curr = root.next
+        while curr is not root:
+            yield curr.key
+            curr = curr.next
+
+    def __reversed__(self):
+        'od.__reversed__() <==> reversed(od)'
+        # Traverse the linked list in reverse order.
+        root = self.__root
+        curr = root.prev
+        while curr is not root:
+            yield curr.key
+            curr = curr.prev
+
+    def clear(self):
+        'od.clear() -> None.  Remove all items from od.'
+        root = self.__root
+        root.prev = root.next = root
+        self.__map.clear()
+        dict.clear(self)
+
+    def popitem(self, last=True):
+        '''od.popitem() -> (k, v), return and remove a (key, value) pair.
+        Pairs are returned in LIFO order if last is true or FIFO order if false.
+
+        '''
+        if not self:
+            raise KeyError('dictionary is empty')
+        root = self.__root
+        if last:
+            link = root.prev
+            link_prev = link.prev
+            link_prev.next = root
+            root.prev = link_prev
+        else:
+            link = root.next
+            link_next = link.next
+            root.next = link_next
+            link_next.prev = root
+        key = link.key
+        del self.__map[key]
+        value = dict.pop(self, key)
+        return key, value
+
+    def move_to_end(self, key, last=True):
+        '''Move an existing element to the end (or beginning if last==False).
+
+        Raises KeyError if the element does not exist.
+        When last=True, acts like a fast version of self[key]=self.pop(key).
+
+        '''
+        link = self.__map[key]
+        link_prev = link.prev
+        link_next = link.next
+        link_prev.next = link_next
+        link_next.prev = link_prev
+        root = self.__root
+        if last:
+            last = root.prev
+            link.prev = last
+            link.next = root
+            last.next = root.prev = link
+        else:
+            first = root.next
+            link.prev = root
+            link.next = first
+            root.next = first.prev = link
+
+    def __sizeof__(self):
+        sizeof = _sys.getsizeof
+        n = len(self) + 1                       # number of links including root
+        size = sizeof(self.__dict__)            # instance dictionary
+        size += sizeof(self.__map) * 2          # internal dict and inherited dict
+        size += sizeof(self.__hardroot) * n     # link objects
+        size += sizeof(self.__root) * n         # proxy objects
+        return size
+
+    update = __update = MutableMapping.update
+    keys = MutableMapping.keys
+    values = MutableMapping.values
+    items = MutableMapping.items
+    __ne__ = MutableMapping.__ne__
+
+    __marker = object()
+
+    def pop(self, key, default=__marker):
+        '''od.pop(k[,d]) -> v, remove specified key and return the corresponding
+        value.  If key is not found, d is returned if given, otherwise KeyError
+        is raised.
+
+        '''
+        if key in self:
+            result = self[key]
+            del self[key]
+            return result
+        if default is self.__marker:
+            raise KeyError(key)
+        return default
+
+    def setdefault(self, key, default=None):
+        'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od'
+        if key in self:
+            return self[key]
+        self[key] = default
+        return default
+
+    @_recursive_repr()
+    def __repr__(self):
+        'od.__repr__() <==> repr(od)'
+        if not self:
+            return '%s()' % (self.__class__.__name__,)
+        return '%s(%r)' % (self.__class__.__name__, list(self.items()))
+
+    def __reduce__(self):
+        'Return state information for pickling'
+        items = [[k, self[k]] for k in self]
+        inst_dict = vars(self).copy()
+        for k in vars(OrderedDict()):
+            inst_dict.pop(k, None)
+        if inst_dict:
+            return (self.__class__, (items,), inst_dict)
+        return self.__class__, (items,)
+
+    def copy(self):
+        'od.copy() -> a shallow copy of od'
+        return self.__class__(self)
+
+    @classmethod
+    def fromkeys(cls, iterable, value=None):
+        '''OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S.
+        If not specified, the value defaults to None.
+
+        '''
+        self = cls()
+        for key in iterable:
+            self[key] = value
+        return self
+
+    def __eq__(self, other):
+        '''od.__eq__(y) <==> od==y.  Comparison to another OD is order-sensitive
+        while comparison to a regular mapping is order-insensitive.
+
+        '''
+        if isinstance(other, OrderedDict):
+            return len(self)==len(other) and \
+                   all(p==q for p, q in zip(self.items(), other.items()))
+        return dict.__eq__(self, other)
+
+# update_wrapper() and wraps() are tools to help write
+# wrapper functions that can handle naive introspection
+
+WRAPPER_ASSIGNMENTS = ('__module__', '__name__', '__doc__')
+WRAPPER_UPDATES = ('__dict__',)
+def update_wrapper(wrapper,
+                   wrapped,
+                   assigned = WRAPPER_ASSIGNMENTS,
+                   updated = WRAPPER_UPDATES):
+    """Update a wrapper function to look like the wrapped function
+
+       wrapper is the function to be updated
+       wrapped is the original function
+       assigned is a tuple naming the attributes assigned directly
+       from the wrapped function to the wrapper function (defaults to
+       functools.WRAPPER_ASSIGNMENTS)
+       updated is a tuple naming the attributes of the wrapper that
+       are updated with the corresponding attribute from the wrapped
+       function (defaults to functools.WRAPPER_UPDATES)
+    """
+    wrapper.__wrapped__ = wrapped
+    for attr in assigned:
+        try:
+            value = getattr(wrapped, attr)
+        except AttributeError:
+            pass
+        else:
+            setattr(wrapper, attr, value)
+    for attr in updated:
+        getattr(wrapper, attr).update(getattr(wrapped, attr, {}))
+    # Return the wrapper so this can be used as a decorator via partial()
+    return wrapper
+
+def wraps(wrapped,
+          assigned = WRAPPER_ASSIGNMENTS,
+          updated = WRAPPER_UPDATES):
+    """Decorator factory to apply update_wrapper() to a wrapper function
+
+       Returns a decorator that invokes update_wrapper() with the decorated
+       function as the wrapper argument and the arguments to wraps() as the
+       remaining arguments. Default arguments are as for update_wrapper().
+       This is a convenience function to simplify applying partial() to
+       update_wrapper().
+    """
+    return partial(update_wrapper, wrapped=wrapped,
+                   assigned=assigned, updated=updated)
+
+def total_ordering(cls):
+    """Class decorator that fills in missing ordering methods"""
+    convert = {
+        '__lt__': [('__gt__', lambda self, other: not (self < other or self == other)),
+                   ('__le__', lambda self, other: self < other or self == other),
+                   ('__ge__', lambda self, other: not self < other)],
+        '__le__': [('__ge__', lambda self, other: not self <= other or self == other),
+                   ('__lt__', lambda self, other: self <= other and not self == other),
+                   ('__gt__', lambda self, other: not self <= other)],
+        '__gt__': [('__lt__', lambda self, other: not (self > other or self == other)),
+                   ('__ge__', lambda self, other: self > other or self == other),
+                   ('__le__', lambda self, other: not self > other)],
+        '__ge__': [('__le__', lambda self, other: (not self >= other) or self == other),
+                   ('__gt__', lambda self, other: self >= other and not self == other),
+                   ('__lt__', lambda self, other: not self >= other)]
+    }
+    roots = set(dir(cls)) & set(convert)
+    if not roots:
+        raise ValueError('must define at least one ordering operation: < > <= >=')
+    root = max(roots)       # prefer __lt__ to __le__ to __gt__ to __ge__
+    for opname, opfunc in convert[root]:
+        if opname not in roots:
+            opfunc.__name__ = opname
+            opfunc.__doc__ = getattr(int, opname).__doc__
+            setattr(cls, opname, opfunc)
+    return cls
+
+def cmp_to_key(mycmp):
+    """Convert a cmp= function into a key= function"""
+    class K(object):
+        __slots__ = ['obj']
+        def __init__(self, obj):
+            self.obj = obj
+        def __lt__(self, other):
+            return mycmp(self.obj, other.obj) < 0
+        def __gt__(self, other):
+            return mycmp(self.obj, other.obj) > 0
+        def __eq__(self, other):
+            return mycmp(self.obj, other.obj) == 0
+        def __le__(self, other):
+            return mycmp(self.obj, other.obj) <= 0
+        def __ge__(self, other):
+            return mycmp(self.obj, other.obj) >= 0
+        def __ne__(self, other):
+            return mycmp(self.obj, other.obj) != 0
+        __hash__ = None
+    return K
+
+_CacheInfo = namedtuple("CacheInfo", "hits misses maxsize currsize")
+
+def lru_cache(maxsize=100):
+    """Least-recently-used cache decorator.
+
+    If *maxsize* is set to None, the LRU features are disabled and the cache
+    can grow without bound.
+
+    Arguments to the cached function must be hashable.
+
+    View the cache statistics named tuple (hits, misses, maxsize, currsize) with
+    f.cache_info().  Clear the cache and statistics with f.cache_clear().
+    Access the underlying function with f.__wrapped__.
+
+    See:  http://en.wikipedia.org/wiki/Cache_algorithms#Least_Recently_Used
+
+    """
+    # Users should only access the lru_cache through its public API:
+    #       cache_info, cache_clear, and f.__wrapped__
+    # The internals of the lru_cache are encapsulated for thread safety and
+    # to allow the implementation to change (including a possible C version).
+
+    def decorating_function(user_function,
+                tuple=tuple, sorted=sorted, len=len, KeyError=KeyError):
+
+        hits, misses = [0], [0]
+        kwd_mark = (object(),)          # separates positional and keyword args
+        lock = Lock()                   # needed because OrderedDict isn't threadsafe
+
+        if maxsize is None:
+            cache = dict()              # simple cache without ordering or size limit
+
+            @wraps(user_function)
+            def wrapper(*args, **kwds):
+                key = args
+                if kwds:
+                    key += kwd_mark + tuple(sorted(kwds.items()))
+                try:
+                    result = cache[key]
+                    hits[0] += 1
+                    return result
+                except KeyError:
+                    pass
+                result = user_function(*args, **kwds)
+                cache[key] = result
+                misses[0] += 1
+                return result
+        else:
+            cache = OrderedDict()           # ordered least recent to most recent
+            cache_popitem = cache.popitem
+            cache_renew = cache.move_to_end
+
+            @wraps(user_function)
+            def wrapper(*args, **kwds):
+                key = args
+                if kwds:
+                    key += kwd_mark + tuple(sorted(kwds.items()))
+                with lock:
+                    try:
+                        result = cache[key]
+                        cache_renew(key)    # record recent use of this key
+                        hits[0] += 1
+                        return result
+                    except KeyError:
+                        pass
+                result = user_function(*args, **kwds)
+                with lock:
+                    cache[key] = result     # record recent use of this key
+                    misses[0] += 1
+                    if len(cache) > maxsize:
+                        cache_popitem(0)    # purge least recently used cache entry
+                return result
+
+        def cache_info():
+            """Report cache statistics"""
+            with lock:
+                return _CacheInfo(hits[0], misses[0], maxsize, len(cache))
+
+        def cache_clear():
+            """Clear the cache and cache statistics"""
+            with lock:
+                cache.clear()
+                hits[0] = misses[0] = 0
+
+        wrapper.cache_info = cache_info
+        wrapper.cache_clear = cache_clear
+        return wrapper
+
+    return decorating_function

lib/spack/external/py2/functools32/reprlib32.py

@@ -0,0 +1,157 @@
+"""Redo the builtin repr() (representation) but with limits on most sizes."""
+
+__all__ = ["Repr", "repr", "recursive_repr"]
+
+import __builtin__ as builtins
+from itertools import islice
+try:
+    from thread import get_ident
+except ImportError:
+    from _dummy_thread32 import get_ident
+
+def recursive_repr(fillvalue='...'):
+    'Decorator to make a repr function return fillvalue for a recursive call'
+
+    def decorating_function(user_function):
+        repr_running = set()
+
+        def wrapper(self):
+            key = id(self), get_ident()
+            if key in repr_running:
+                return fillvalue
+            repr_running.add(key)
+            try:
+                result = user_function(self)
+            finally:
+                repr_running.discard(key)
+            return result
+
+        # Can't use functools.wraps() here because of bootstrap issues
+        wrapper.__module__ = getattr(user_function, '__module__')
+        wrapper.__doc__ = getattr(user_function, '__doc__')
+        wrapper.__name__ = getattr(user_function, '__name__')
+        wrapper.__annotations__ = getattr(user_function, '__annotations__', {})
+        return wrapper
+
+    return decorating_function
+
+class Repr:
+
+    def __init__(self):
+        self.maxlevel = 6
+        self.maxtuple = 6
+        self.maxlist = 6
+        self.maxarray = 5
+        self.maxdict = 4
+        self.maxset = 6
+        self.maxfrozenset = 6
+        self.maxdeque = 6
+        self.maxstring = 30
+        self.maxlong = 40
+        self.maxother = 30
+
+    def repr(self, x):
+        return self.repr1(x, self.maxlevel)
+
+    def repr1(self, x, level):
+        typename = type(x).__name__
+        if ' ' in typename:
+            parts = typename.split()
+            typename = '_'.join(parts)
+        if hasattr(self, 'repr_' + typename):
+            return getattr(self, 'repr_' + typename)(x, level)
+        else:
+            return self.repr_instance(x, level)
+
+    def _repr_iterable(self, x, level, left, right, maxiter, trail=''):
+        n = len(x)
+        if level <= 0 and n:
+            s = '...'
+        else:
+            newlevel = level - 1
+            repr1 = self.repr1
+            pieces = [repr1(elem, newlevel) for elem in islice(x, maxiter)]
+            if n > maxiter:  pieces.append('...')
+            s = ', '.join(pieces)
+            if n == 1 and trail:  right = trail + right
+        return '%s%s%s' % (left, s, right)
+
+    def repr_tuple(self, x, level):
+        return self._repr_iterable(x, level, '(', ')', self.maxtuple, ',')
+
+    def repr_list(self, x, level):
+        return self._repr_iterable(x, level, '[', ']', self.maxlist)
+
+    def repr_array(self, x, level):
+        header = "array('%s', [" % x.typecode
+        return self._repr_iterable(x, level, header, '])', self.maxarray)
+
+    def repr_set(self, x, level):
+        x = _possibly_sorted(x)
+        return self._repr_iterable(x, level, 'set([', '])', self.maxset)
+
+    def repr_frozenset(self, x, level):
+        x = _possibly_sorted(x)
+        return self._repr_iterable(x, level, 'frozenset([', '])',
+                                   self.maxfrozenset)
+
+    def repr_deque(self, x, level):
+        return self._repr_iterable(x, level, 'deque([', '])', self.maxdeque)
+
+    def repr_dict(self, x, level):
+        n = len(x)
+        if n == 0: return '{}'
+        if level <= 0: return '{...}'
+        newlevel = level - 1
+        repr1 = self.repr1
+        pieces = []
+        for key in islice(_possibly_sorted(x), self.maxdict):
+            keyrepr = repr1(key, newlevel)
+            valrepr = repr1(x[key], newlevel)
+            pieces.append('%s: %s' % (keyrepr, valrepr))
+        if n > self.maxdict: pieces.append('...')
+        s = ', '.join(pieces)
+        return '{%s}' % (s,)
+
+    def repr_str(self, x, level):
+        s = builtins.repr(x[:self.maxstring])
+        if len(s) > self.maxstring:
+            i = max(0, (self.maxstring-3)//2)
+            j = max(0, self.maxstring-3-i)
+            s = builtins.repr(x[:i] + x[len(x)-j:])
+            s = s[:i] + '...' + s[len(s)-j:]
+        return s
+
+    def repr_int(self, x, level):
+        s = builtins.repr(x) # XXX Hope this isn't too slow...
+        if len(s) > self.maxlong:
+            i = max(0, (self.maxlong-3)//2)
+            j = max(0, self.maxlong-3-i)
+            s = s[:i] + '...' + s[len(s)-j:]
+        return s
+
+    def repr_instance(self, x, level):
+        try:
+            s = builtins.repr(x)
+            # Bugs in x.__repr__() can cause arbitrary
+            # exceptions -- then make up something
+        except Exception:
+            return '<%s instance at %x>' % (x.__class__.__name__, id(x))
+        if len(s) > self.maxother:
+            i = max(0, (self.maxother-3)//2)
+            j = max(0, self.maxother-3-i)
+            s = s[:i] + '...' + s[len(s)-j:]
+        return s
+
+
+def _possibly_sorted(x):
+    # Since not all sequences of items can be sorted and comparison
+    # functions may raise arbitrary exceptions, return an unsorted
+    # sequence in that case.
+    try:
+        return sorted(x)
+    except Exception:
+        return list(x)
+
+aRepr = Repr()
+repr = aRepr.repr

lib/spack/external/py2/typing.py

@@ -0,0 +1,103 @@
+# 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)
+"""
+This is a fake set of symbols to allow spack to import typing in python
+versions where we do not support type checking (<3)
+"""
+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
+
+## 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/util/argparsewriter.py

@@ -7,10 +7,11 @@
 
 import argparse
 import errno
-import io
 import re
 import sys
 
+from six import StringIO
+
 
 class Command(object):
     """Parsed representation of a command from argparse.
@@ -28,8 +29,8 @@ class Command(object):
       - optionals: list of optional arguments (list)
       - subcommands: list of subcommand parsers (list)
     """
-
-    def __init__(self, prog, description, usage, positionals, optionals, subcommands):
+    def __init__(self, prog, description, usage,
+                 positionals, optionals, subcommands):
         self.prog = prog
         self.description = description
         self.usage = usage
@@ -70,15 +71,15 @@ def parse(self, parser, prog):
         """
         self.parser = parser
 
-        split_prog = parser.prog.split(" ")
+        split_prog = parser.prog.split(' ')
         split_prog[-1] = prog
-        prog = " ".join(split_prog)
+        prog = ' '.join(split_prog)
         description = parser.description
 
         fmt = parser._get_formatter()
         actions = parser._actions
         groups = parser._mutually_exclusive_groups
-        usage = fmt._format_usage(None, actions, groups, "").strip()
+        usage = fmt._format_usage(None, actions, groups, '').strip()
 
         # Go through actions and split them into optionals, positionals,
         # and subcommands
@@ -89,8 +90,8 @@ def parse(self, parser, prog):
             if action.option_strings:
                 flags = action.option_strings
                 dest_flags = fmt._format_action_invocation(action)
-                help = self._expand_help(action) if action.help else ""
-                help = help.replace("\n", " ")
+                help = self._expand_help(action) if action.help else ''
+                help = help.replace('\n', ' ')
                 optionals.append((flags, dest_flags, help))
             elif isinstance(action, argparse._SubParsersAction):
                 for subaction in action._choices_actions:
@@ -99,19 +100,20 @@ def parse(self, parser, prog):
 
                     # Look for aliases of the form 'name (alias, ...)'
                     if self.aliases:
-                        match = re.match(r"(.*) \((.*)\)", subaction.metavar)
+                        match = re.match(r'(.*) \((.*)\)', subaction.metavar)
                         if match:
-                            aliases = match.group(2).split(", ")
+                            aliases = match.group(2).split(', ')
                             for alias in aliases:
                                 subparser = action._name_parser_map[alias]
                                 subcommands.append((subparser, alias))
             else:
                 args = fmt._format_action_invocation(action)
-                help = self._expand_help(action) if action.help else ""
-                help = help.replace("\n", " ")
+                help = self._expand_help(action) if action.help else ''
+                help = help.replace('\n', ' ')
                 positionals.append((args, help))
 
-        return Command(prog, description, usage, positionals, optionals, subcommands)
+        return Command(
+            prog, description, usage, positionals, optionals, subcommands)
 
     def format(self, cmd):
         """Returns the string representation of a single node in the
@@ -159,13 +161,14 @@ def write(self, parser):
                 raise
 
 
-_rst_levels = ["=", "-", "^", "~", ":", "`"]
+_rst_levels = ['=', '-', '^', '~', ':', '`']
 
 
 class ArgparseRstWriter(ArgparseWriter):
     """Write argparse output as rst sections."""
 
-    def __init__(self, prog, out=None, aliases=False, rst_levels=_rst_levels):
+    def __init__(self, prog, out=None, aliases=False,
+                 rst_levels=_rst_levels):
         """Create a new ArgparseRstWriter.
 
         Parameters:
@@ -180,7 +183,7 @@ def __init__(self, prog, out=None, aliases=False, rst_levels=_rst_levels):
         self.rst_levels = rst_levels
 
     def format(self, cmd):
-        string = io.StringIO()
+        string = StringIO()
         string.write(self.begin_command(cmd.prog))
 
         if cmd.description:
@@ -214,12 +217,11 @@ def begin_command(self, prog):
 {1}
 {2}
 
-""".format(
-            prog.replace(" ", "-"), prog, self.rst_levels[self.level] * len(prog)
-        )
+""".format(prog.replace(' ', '-'), prog,
+           self.rst_levels[self.level] * len(prog))
 
     def description(self, description):
-        return description + "\n\n"
+        return description + '\n\n'
 
     def usage(self, usage):
         return """\
@@ -227,39 +229,33 @@ def usage(self, usage):
 
     {0}
 
-""".format(
-            usage
-        )
+""".format(usage)
 
     def begin_positionals(self):
-        return "\n**Positional arguments**\n\n"
+        return '\n**Positional arguments**\n\n'
 
     def positional(self, name, help):
         return """\
 {0}
   {1}
 
-""".format(
-            name, help
-        )
+""".format(name, help)
 
     def end_positionals(self):
-        return ""
+        return ''
 
     def begin_optionals(self):
-        return "\n**Optional arguments**\n\n"
+        return '\n**Optional arguments**\n\n'
 
     def optional(self, opts, help):
         return """\
 ``{0}``
   {1}
 
-""".format(
-            opts, help
-        )
+""".format(opts, help)
 
     def end_optionals(self):
-        return ""
+        return ''
 
     def begin_subcommands(self, subcommands):
         string = """
@@ -271,10 +267,11 @@ def begin_subcommands(self, subcommands):
 """
 
         for cmd, _ in subcommands:
-            prog = re.sub(r"^[^ ]* ", "", cmd.prog)
-            string += "   * :ref:`{0} <{1}>`\n".format(prog, cmd.prog.replace(" ", "-"))
+            prog = re.sub(r'^[^ ]* ', '', cmd.prog)
+            string += '   * :ref:`{0} <{1}>`\n'.format(
+                prog, cmd.prog.replace(' ', '-'))
 
-        return string + "\n"
+        return string + '\n'
 
 
 class ArgparseCompletionWriter(ArgparseWriter):
@@ -309,11 +306,9 @@ def format(self, cmd):
         # Flatten lists of lists
         optionals = [x for xx in optionals for x in xx]
 
-        return (
-            self.start_function(cmd.prog)
-            + self.body(positionals, optionals, subcommands)
-            + self.end_function(cmd.prog)
-        )
+        return (self.start_function(cmd.prog) +
+                self.body(positionals, optionals, subcommands) +
+                self.end_function(cmd.prog))
 
     def start_function(self, prog):
         """Returns the syntax needed to begin a function definition.
@@ -324,8 +319,8 @@ def start_function(self, prog):
         Returns:
             str: the function definition beginning
         """
-        name = prog.replace("-", "_").replace(" ", "_")
-        return "\n_{0}() {{".format(name)
+        name = prog.replace('-', '_').replace(' ', '_')
+        return '\n_{0}() {{'.format(name)
 
     def end_function(self, prog=None):
         """Returns the syntax needed to end a function definition.
@@ -336,7 +331,7 @@ def end_function(self, prog=None):
         Returns:
             str: the function definition ending
         """
-        return "}\n"
+        return '}\n'
 
     def body(self, positionals, optionals, subcommands):
         """Returns the body of the function.
@@ -349,7 +344,7 @@ def body(self, positionals, optionals, subcommands):
         Returns:
             str: the function body
         """
-        return ""
+        return ''
 
     def positionals(self, positionals):
         """Returns the syntax for reporting positional arguments.
@@ -360,7 +355,7 @@ def positionals(self, positionals):
         Returns:
             str: the syntax for positional arguments
         """
-        return ""
+        return ''
 
     def optionals(self, optionals):
         """Returns the syntax for reporting optional flags.
@@ -371,7 +366,7 @@ def optionals(self, optionals):
         Returns:
             str: the syntax for optional flags
         """
-        return ""
+        return ''
 
     def subcommands(self, subcommands):
         """Returns the syntax for reporting subcommands.
@@ -382,4 +377,4 @@ def subcommands(self, subcommands):
         Returns:
             str: the syntax for subcommand parsers
         """
-        return ""
+        return ''

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/lang.py

@@ -5,20 +5,23 @@
 
 from __future__ import division
 
-import collections.abc
 import contextlib
 import functools
 import inspect
-import itertools
 import os
 import re
 import sys
 import traceback
 from datetime import datetime, timedelta
-from typing import Any, Callable, Iterable, List, Tuple
+from typing import List, Tuple
+
+import six
+from six import string_types
+
+from llnl.util.compat import MutableMapping, MutableSequence, zip_longest
 
 # Ignore emacs backups when listing modules
-ignore_modules = [r"^\.#", "~$"]
+ignore_modules = [r'^\.#', '~$']
 
 
 def index_by(objects, *funcs):
@@ -88,9 +91,9 @@ def index_by(objects, *funcs):
 
 def caller_locals():
     """This will return the locals of the *parent* of the caller.
-    This allows a function to insert variables into its caller's
-    scope.  Yes, this is some black magic, and yes it's useful
-    for implementing things like depends_on and provides.
+       This allows a function to insert variables into its caller's
+       scope.  Yes, this is some black magic, and yes it's useful
+       for implementing things like depends_on and provides.
     """
     # Passing zero here skips line context for speed.
     stack = inspect.stack(0)
@@ -102,7 +105,7 @@ def caller_locals():
 
 def get_calling_module_name():
     """Make sure that the caller is a class definition, and return the
-    enclosing module's name.
+       enclosing module's name.
     """
     # Passing zero here skips line context for speed.
     stack = inspect.stack(0)
@@ -112,13 +115,12 @@ def get_calling_module_name():
     finally:
         del stack
 
-    if "__module__" not in caller_locals:
-        raise RuntimeError(
-            "Must invoke get_calling_module_name() " "from inside a class definition!"
-        )
+    if '__module__' not in caller_locals:
+        raise RuntimeError("Must invoke get_calling_module_name() "
+                           "from inside a class definition!")
 
-    module_name = caller_locals["__module__"]
-    base_name = module_name.split(".")[-1]
+    module_name = caller_locals['__module__']
+    base_name = module_name.split('.')[-1]
     return base_name
 
 
@@ -126,8 +128,8 @@ def attr_required(obj, attr_name):
     """Ensure that a class has a required attribute."""
     if not hasattr(obj, attr_name):
         raise RequiredAttributeError(
-            "No required attribute '%s' in class '%s'" % (attr_name, obj.__class__.__name__)
-        )
+            "No required attribute '%s' in class '%s'"
+            % (attr_name, obj.__class__.__name__))
 
 
 def attr_setdefault(obj, name, value):
@@ -197,32 +199,35 @@ def _memoized_function(*args, **kwargs):
             return ret
         except TypeError as e:
             # TypeError is raised when indexing into a dict if the key is unhashable.
-            raise UnhashableArguments(
-                "args + kwargs '{}' was not hashable for function '{}'".format(key, func.__name__),
-            ) from e
+            raise six.raise_from(
+                UnhashableArguments(
+                    "args + kwargs '{}' was not hashable for function '{}'"
+                    .format(key, func.__name__),
+                ),
+                e)
 
     return _memoized_function
 
 
 def list_modules(directory, **kwargs):
     """Lists all of the modules, excluding ``__init__.py``, in a
-    particular directory.  Listed packages have no particular
-    order."""
-    list_directories = kwargs.setdefault("directories", True)
+       particular directory.  Listed packages have no particular
+       order."""
+    list_directories = kwargs.setdefault('directories', True)
 
     for name in os.listdir(directory):
-        if name == "__init__.py":
+        if name == '__init__.py':
             continue
 
         path = os.path.join(directory, name)
         if list_directories and os.path.isdir(path):
-            init_py = os.path.join(path, "__init__.py")
+            init_py = os.path.join(path, '__init__.py')
             if os.path.isfile(init_py):
                 yield name
 
-        elif name.endswith(".py"):
+        elif name.endswith('.py'):
             if not any(re.search(pattern, name) for pattern in ignore_modules):
-                yield re.sub(".py$", "", name)
+                yield re.sub('.py$', '', name)
 
 
 def decorator_with_or_without_args(decorator):
@@ -252,34 +257,41 @@ def new_dec(*args, **kwargs):
 
 def key_ordering(cls):
     """Decorates a class with extra methods that implement rich comparison
-    operations and ``__hash__``.  The decorator assumes that the class
-    implements a function called ``_cmp_key()``.  The rich comparison
-    operations will compare objects using this key, and the ``__hash__``
-    function will return the hash of this key.
+       operations and ``__hash__``.  The decorator assumes that the class
+       implements a function called ``_cmp_key()``.  The rich comparison
+       operations will compare objects using this key, and the ``__hash__``
+       function will return the hash of this key.
 
-    If a class already has ``__eq__``, ``__ne__``, ``__lt__``, ``__le__``,
-    ``__gt__``, or ``__ge__`` defined, this decorator will overwrite them.
+       If a class already has ``__eq__``, ``__ne__``, ``__lt__``, ``__le__``,
+       ``__gt__``, or ``__ge__`` defined, this decorator will overwrite them.
 
-    Raises:
-        TypeError: If the class does not have a ``_cmp_key`` method
+       Raises:
+           TypeError: If the class does not have a ``_cmp_key`` method
     """
-
     def setter(name, value):
         value.__name__ = name
         setattr(cls, name, value)
 
-    if not has_method(cls, "_cmp_key"):
+    if not has_method(cls, '_cmp_key'):
         raise TypeError("'%s' doesn't define _cmp_key()." % cls.__name__)
 
-    setter("__eq__", lambda s, o: (s is o) or (o is not None and s._cmp_key() == o._cmp_key()))
-    setter("__lt__", lambda s, o: o is not None and s._cmp_key() < o._cmp_key())
-    setter("__le__", lambda s, o: o is not None and s._cmp_key() <= o._cmp_key())
+    setter('__eq__',
+           lambda s, o:
+           (s is o) or (o is not None and s._cmp_key() == o._cmp_key()))
+    setter('__lt__',
+           lambda s, o: o is not None and s._cmp_key() < o._cmp_key())
+    setter('__le__',
+           lambda s, o: o is not None and s._cmp_key() <= o._cmp_key())
 
-    setter("__ne__", lambda s, o: (s is not o) and (o is None or s._cmp_key() != o._cmp_key()))
-    setter("__gt__", lambda s, o: o is None or s._cmp_key() > o._cmp_key())
-    setter("__ge__", lambda s, o: o is None or s._cmp_key() >= o._cmp_key())
+    setter('__ne__',
+           lambda s, o:
+           (s is not o) and (o is None or s._cmp_key() != o._cmp_key()))
+    setter('__gt__',
+           lambda s, o: o is None or s._cmp_key() > o._cmp_key())
+    setter('__ge__',
+           lambda s, o: o is None or s._cmp_key() >= o._cmp_key())
 
-    setter("__hash__", lambda self: hash(self._cmp_key()))
+    setter('__hash__', lambda self: hash(self._cmp_key()))
 
     return cls
 
@@ -304,7 +316,7 @@ def lazy_eq(lseq, rseq):
     # zip_longest is implemented in native code, so use it for speed.
     # use zip_longest instead of zip because it allows us to tell
     # which iterator was longer.
-    for left, right in itertools.zip_longest(liter, riter, fillvalue=done):
+    for left, right in zip_longest(liter, riter, fillvalue=done):
         if (left is done) or (right is done):
             return False
 
@@ -324,7 +336,7 @@ def lazy_lt(lseq, rseq):
     liter = lseq()
     riter = rseq()
 
-    for left, right in itertools.zip_longest(liter, riter, fillvalue=done):
+    for left, right in zip_longest(liter, riter, fillvalue=done):
         if (left is done) or (right is done):
             return left is done  # left was shorter than right
 
@@ -446,7 +458,8 @@ def gt(self, other):
     def le(self, other):
         if self is other:
             return True
-        return (other is not None) and not lazy_lt(other._cmp_iter, self._cmp_iter)
+        return (other is not None) and not lazy_lt(other._cmp_iter,
+                                                   self._cmp_iter)
 
     def ge(self, other):
         if self is other:
@@ -474,11 +487,9 @@ def add_func_to_class(name, func):
 
 
 @lazy_lexicographic_ordering
-class HashableMap(collections.abc.MutableMapping):
+class HashableMap(MutableMapping):
     """This is a hashable, comparable dictionary.  Hash is performed on
-    a tuple of the values in the dictionary."""
-
-    __slots__ = ("dict",)
+       a tuple of the values in the dictionary."""
 
     def __init__(self):
         self.dict = {}
@@ -516,7 +527,7 @@ def copy(self):
 
 def in_function(function_name):
     """True if the caller was called from some function with
-    the supplied Name, False otherwise."""
+       the supplied Name, False otherwise."""
     stack = inspect.stack()
     try:
         for elt in stack[2:]:
@@ -529,25 +540,24 @@ def in_function(function_name):
 
 def check_kwargs(kwargs, fun):
     """Helper for making functions with kwargs.  Checks whether the kwargs
-    are empty after all of them have been popped off.  If they're
-    not, raises an error describing which kwargs are invalid.
+       are empty after all of them have been popped off.  If they're
+       not, raises an error describing which kwargs are invalid.
 
-    Example::
+       Example::
 
-       def foo(self, **kwargs):
-           x = kwargs.pop('x', None)
-           y = kwargs.pop('y', None)
-           z = kwargs.pop('z', None)
-           check_kwargs(kwargs, self.foo)
+          def foo(self, **kwargs):
+              x = kwargs.pop('x', None)
+              y = kwargs.pop('y', None)
+              z = kwargs.pop('z', None)
+              check_kwargs(kwargs, self.foo)
 
-       # This raises a TypeError:
-       foo(w='bad kwarg')
+          # This raises a TypeError:
+          foo(w='bad kwarg')
     """
     if kwargs:
         raise TypeError(
             "'%s' is an invalid keyword argument for function %s()."
-            % (next(iter(kwargs)), fun.__name__)
-        )
+            % (next(iter(kwargs)), fun.__name__))
 
 
 def match_predicate(*args):
@@ -563,10 +573,9 @@ def match_predicate(*args):
     * any regex in a list or tuple of regexes matches.
     * any predicate in args matches.
     """
-
     def match(string):
         for arg in args:
-            if isinstance(arg, str):
+            if isinstance(arg, string_types):
                 if re.search(arg, string):
                     return True
             elif isinstance(arg, list) or isinstance(arg, tuple):
@@ -576,11 +585,9 @@ def match(string):
                 if arg(string):
                     return True
             else:
-                raise ValueError(
-                    "args to match_predicate must be regex, " "list of regexes, or callable."
-                )
+                raise ValueError("args to match_predicate must be regex, "
+                                 "list of regexes, or callable.")
         return False
-
     return match
 
 
@@ -640,7 +647,7 @@ def pretty_date(time, now=None):
     day_diff = diff.days
 
     if day_diff < 0:
-        return ""
+        return ''
 
     if day_diff == 0:
         if second_diff < 10:
@@ -698,40 +705,43 @@ def pretty_string_to_date(date_str, now=None):
     now = now or datetime.now()
 
     # datetime formats
-    pattern[re.compile(r"^\d{4}$")] = lambda x: datetime.strptime(x, "%Y")
-    pattern[re.compile(r"^\d{4}-\d{2}$")] = lambda x: datetime.strptime(x, "%Y-%m")
-    pattern[re.compile(r"^\d{4}-\d{2}-\d{2}$")] = lambda x: datetime.strptime(x, "%Y-%m-%d")
-    pattern[re.compile(r"^\d{4}-\d{2}-\d{2} \d{2}:\d{2}$")] = lambda x: datetime.strptime(
-        x, "%Y-%m-%d %H:%M"
+    pattern[re.compile(r'^\d{4}$')] = lambda x: datetime.strptime(x, '%Y')
+    pattern[re.compile(r'^\d{4}-\d{2}$')] = lambda x: datetime.strptime(
+        x, '%Y-%m'
     )
-    pattern[re.compile(r"^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$")] = lambda x: datetime.strptime(
-        x, "%Y-%m-%d %H:%M:%S"
+    pattern[re.compile(r'^\d{4}-\d{2}-\d{2}$')] = lambda x: datetime.strptime(
+        x, '%Y-%m-%d'
     )
+    pattern[re.compile(r'^\d{4}-\d{2}-\d{2} \d{2}:\d{2}$')] = \
+        lambda x: datetime.strptime(x, '%Y-%m-%d %H:%M')
+    pattern[re.compile(r'^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$')] = \
+        lambda x: datetime.strptime(x, '%Y-%m-%d %H:%M:%S')
 
-    pretty_regex = re.compile(r"(a|\d+)\s*(year|month|week|day|hour|minute|second)s?\s*ago")
+    pretty_regex = re.compile(
+        r'(a|\d+)\s*(year|month|week|day|hour|minute|second)s?\s*ago')
 
     def _n_xxx_ago(x):
         how_many, time_period = pretty_regex.search(x).groups()
 
-        how_many = 1 if how_many == "a" else int(how_many)
+        how_many = 1 if how_many == 'a' else int(how_many)
 
         # timedelta natively supports time periods up to 'weeks'.
         # To apply month or year we convert to 30 and 365 days
-        if time_period == "month":
+        if time_period == 'month':
             how_many *= 30
-            time_period = "day"
-        elif time_period == "year":
+            time_period = 'day'
+        elif time_period == 'year':
             how_many *= 365
-            time_period = "day"
+            time_period = 'day'
 
-        kwargs = {(time_period + "s"): how_many}
+        kwargs = {(time_period + 's'): how_many}
         return now - timedelta(**kwargs)
 
     pattern[pretty_regex] = _n_xxx_ago
 
     # yesterday
     callback = lambda x: now - timedelta(days=1)
-    pattern[re.compile("^yesterday$")] = callback
+    pattern[re.compile('^yesterday$')] = callback
 
     for regexp, parser in pattern.items():
         if bool(regexp.match(date_str)):
@@ -741,27 +751,8 @@ def _n_xxx_ago(x):
     raise ValueError(msg)
 
 
-def pretty_seconds(seconds):
-    """Seconds to string with appropriate units
-
-    Arguments:
-        seconds (float): Number of seconds
-
-    Returns:
-        str: Time string with units
-    """
-    if seconds >= 1:
-        value, unit = seconds, "s"
-    elif seconds >= 1e-3:
-        value, unit = seconds * 1e3, "ms"
-    elif seconds >= 1e-6:
-        value, unit = seconds * 1e6, "us"
-    else:
-        value, unit = seconds * 1e9, "ns"
-    return "%.3f%s" % (value, unit)
-
-
 class RequiredAttributeError(ValueError):
+
     def __init__(self, message):
         super(RequiredAttributeError, self).__init__(message)
 
@@ -773,7 +764,6 @@ class ObjectWrapper(object):
     This class is modeled after the stackoverflow answer:
     * http://stackoverflow.com/a/1445289/771663
     """
-
     def __init__(self, wrapped_object):
         wrapped_cls = type(wrapped_object)
         wrapped_name = wrapped_cls.__name__
@@ -817,7 +807,7 @@ def __getattr__(self, name):
         # requested but not yet set. The final 'getattr' line here requires
         # 'instance'/'_instance' to be defined or it will enter an infinite
         # loop, so protect against that here.
-        if name in ["_instance", "instance"]:
+        if name in ['_instance', 'instance']:
             raise AttributeError()
         return getattr(self.instance, name)
 
@@ -847,7 +837,7 @@ def __init__(self, ref_function):
         self.ref_function = ref_function
 
     def __getattr__(self, name):
-        if name == "ref_function":
+        if name == 'ref_function':
             raise AttributeError()
         return getattr(self.ref_function(), name)
 
@@ -879,28 +869,31 @@ def load_module_from_file(module_name, module_path):
         ImportError: when the module can't be loaded
         FileNotFoundError: when module_path doesn't exist
     """
-    import importlib.util
-
     if module_name in sys.modules:
         return sys.modules[module_name]
 
     # This recipe is adapted from https://stackoverflow.com/a/67692/771663
-
-    spec = importlib.util.spec_from_file_location(module_name, module_path)  # novm
-    module = importlib.util.module_from_spec(spec)  # novm
-    # The module object needs to exist in sys.modules before the
-    # loader executes the module code.
-    #
-    # See https://docs.python.org/3/reference/import.html#loading
-    sys.modules[spec.name] = module
-    try:
-        spec.loader.exec_module(module)
-    except BaseException:
+    if sys.version_info[0] == 3 and sys.version_info[1] >= 5:
+        import importlib.util
+        spec = importlib.util.spec_from_file_location(  # novm
+            module_name, module_path)
+        module = importlib.util.module_from_spec(spec)  # novm
+        # The module object needs to exist in sys.modules before the
+        # loader executes the module code.
+        #
+        # See https://docs.python.org/3/reference/import.html#loading
+        sys.modules[spec.name] = module
         try:
-            del sys.modules[spec.name]
-        except KeyError:
-            pass
-        raise
+            spec.loader.exec_module(module)
+        except BaseException:
+            try:
+                del sys.modules[spec.name]
+            except KeyError:
+                pass
+            raise
+    elif sys.version_info[0] == 2:
+        import imp
+        module = imp.load_source(module_name, module_path)
     return module
 
 
@@ -931,10 +924,8 @@ def uniq(sequence):
 
 def star(func):
     """Unpacks arguments for use with Multiprocessing mapping functions"""
-
     def _wrapper(args):
         return func(*args)
-
     return _wrapper
 
 
@@ -943,23 +934,22 @@ class Devnull(object):
 
     See https://stackoverflow.com/a/2929954.
     """
-
     def write(self, *_):
         pass
 
 
 def elide_list(line_list, max_num=10):
     """Takes a long list and limits it to a smaller number of elements,
-    replacing intervening elements with '...'.  For example::
+       replacing intervening elements with '...'.  For example::
 
-        elide_list([1,2,3,4,5,6], 4)
+           elide_list([1,2,3,4,5,6], 4)
 
-    gives::
+       gives::
 
-        [1, 2, 3, '...', 6]
+           [1, 2, 3, '...', 6]
     """
     if len(line_list) > max_num:
-        return line_list[: max_num - 1] + ["..."] + line_list[-1:]
+        return line_list[:max_num - 1] + ['...'] + line_list[-1:]
     else:
         return line_list
 
@@ -982,43 +972,10 @@ def enum(**kwargs):
     Args:
         **kwargs: explicit dictionary of enums
     """
-    return type("Enum", (object,), kwargs)
+    return type('Enum', (object,), kwargs)
 
 
-def stable_partition(
-    input_iterable,  # type: Iterable
-    predicate_fn,  # type: Callable[[Any], bool]
-):
-    # type: (...) -> Tuple[List[Any], List[Any]]
-    """Partition the input iterable according to a custom predicate.
-
-    Args:
-        input_iterable: input iterable to be partitioned.
-        predicate_fn: predicate function accepting an iterable item
-            as argument.
-
-    Return:
-        Tuple of the list of elements evaluating to True, and
-        list of elements evaluating to False.
-    """
-    true_items, false_items = [], []
-    for item in input_iterable:
-        if predicate_fn(item):
-            true_items.append(item)
-            continue
-        false_items.append(item)
-    return true_items, false_items
-
-
-def ensure_last(lst, *elements):
-    """Performs a stable partition of lst, ensuring that ``elements``
-    occur at the end of ``lst`` in specified order. Mutates ``lst``.
-    Raises ``ValueError`` if any ``elements`` are not already in ``lst``."""
-    for elt in elements:
-        lst.append(lst.pop(lst.index(elt)))
-
-
-class TypedMutableSequence(collections.abc.MutableSequence):
+class TypedMutableSequence(MutableSequence):
     """Base class that behaves like a list, just with a different type.
 
     Client code can inherit from this base class:
@@ -1031,7 +988,6 @@ class Foo(TypedMutableSequence):
         if isinstance(l, Foo):
             # do something
     """
-
     def __init__(self, iterable):
         self.data = list(iterable)
 
@@ -1061,7 +1017,7 @@ class GroupedExceptionHandler(object):
     """A generic mechanism to coalesce multiple exceptions and preserve tracebacks."""
 
     def __init__(self):
-        self.exceptions = []  # type: List[Tuple[str, Exception, List[str]]]
+        self.exceptions = []    # type: List[Tuple[str, Exception, List[str]]]
 
     def __bool__(self):
         """Whether any exceptions were handled."""
@@ -1080,15 +1036,17 @@ def grouped_message(self, with_tracebacks=True):
         # type: (bool) -> str
         """Print out an error message coalescing all the forwarded errors."""
         each_exception_message = [
-            "{0} raised {1}: {2}{3}".format(
+            '{0} raised {1}: {2}{3}'.format(
                 context,
                 exc.__class__.__name__,
                 exc,
-                "\n{0}".format("".join(tb)) if with_tracebacks else "",
+                '\n{0}'.format(''.join(tb)) if with_tracebacks else '',
             )
             for context, exc, tb in self.exceptions
         ]
-        return "due to the following failures:\n{0}".format("\n".join(each_exception_message))
+        return 'due to the following failures:\n{0}'.format(
+            '\n'.join(each_exception_message)
+        )
 
 
 class GroupedExceptionForwarder(object):
@@ -1121,7 +1079,6 @@ class classproperty(object):
     the evaluation is injected at creation time and take an instance (could be None) and
     an owner (i.e. the class that originated the instance)
     """
-
     def __init__(self, callback):
         self.callback = callback
 

lib/spack/llnl/util/link_tree.py

@@ -13,12 +13,12 @@
 from collections import OrderedDict
 
 import llnl.util.tty as tty
-from llnl.util.filesystem import BaseDirectoryVisitor, mkdirp, touch, traverse_tree
+from llnl.util.filesystem import mkdirp, touch, traverse_tree
 from llnl.util.symlink import islink, symlink
 
-__all__ = ["LinkTree"]
+__all__ = ['LinkTree']
 
-empty_file_name = ".spack-empty"
+empty_file_name = '.spack-empty'
 
 
 def remove_link(src, dest):
@@ -38,28 +38,26 @@ class MergeConflict:
 
         project(src_a) == project(src_b) == dst
     """
-
     def __init__(self, dst, src_a=None, src_b=None):
         self.dst = dst
         self.src_a = src_a
         self.src_b = src_b
 
 
-class SourceMergeVisitor(BaseDirectoryVisitor):
+class SourceMergeVisitor(object):
     """
     Visitor that produces actions:
     - An ordered list of directories to create in dst
     - A list of files to link in dst
     - A list of merge conflicts in dst/
     """
-
     def __init__(self, ignore=None):
         self.ignore = ignore if ignore is not None else lambda f: False
 
         # When mapping <src root> to <dst root>/<projection>, we need
         # to prepend the <projection> bit to the relative path in the
         # destination dir.
-        self.projection = ""
+        self.projection = ''
 
         # When a file blocks another file, the conflict can sometimes
         # be resolved / ignored (e.g. <prefix>/LICENSE or
@@ -90,13 +88,10 @@ def before_visit_dir(self, root, rel_path, depth):
         elif proj_rel_path in self.files:
             # Can't create a dir where a file is.
             src_a_root, src_a_relpath = self.files[proj_rel_path]
-            self.fatal_conflicts.append(
-                MergeConflict(
-                    dst=proj_rel_path,
-                    src_a=os.path.join(src_a_root, src_a_relpath),
-                    src_b=os.path.join(root, rel_path),
-                )
-            )
+            self.fatal_conflicts.append(MergeConflict(
+                dst=proj_rel_path,
+                src_a=os.path.join(src_a_root, src_a_relpath),
+                src_b=os.path.join(root, rel_path)))
             return False
         elif proj_rel_path in self.directories:
             # No new directory, carry on.
@@ -106,6 +101,9 @@ def before_visit_dir(self, root, rel_path, depth):
             self.directories[proj_rel_path] = (root, rel_path)
             return True
 
+    def after_visit_dir(self, root, rel_path, depth):
+        pass
+
     def before_visit_symlinked_dir(self, root, rel_path, depth):
         """
         Replace symlinked dirs with actual directories when possible in low depths,
@@ -138,6 +136,9 @@ def before_visit_symlinked_dir(self, root, rel_path, depth):
         self.visit_file(root, rel_path, depth)
         return False
 
+    def after_visit_symlinked_dir(self, root, rel_path, depth):
+        pass
+
     def visit_file(self, root, rel_path, depth):
         proj_rel_path = os.path.join(self.projection, rel_path)
 
@@ -146,59 +147,46 @@ def visit_file(self, root, rel_path, depth):
         elif proj_rel_path in self.directories:
             # Can't create a file where a dir is; fatal error
             src_a_root, src_a_relpath = self.directories[proj_rel_path]
-            self.fatal_conflicts.append(
-                MergeConflict(
-                    dst=proj_rel_path,
-                    src_a=os.path.join(src_a_root, src_a_relpath),
-                    src_b=os.path.join(root, rel_path),
-                )
-            )
+            self.fatal_conflicts.append(MergeConflict(
+                dst=proj_rel_path,
+                src_a=os.path.join(src_a_root, src_a_relpath),
+                src_b=os.path.join(root, rel_path)))
         elif proj_rel_path in self.files:
             # In some cases we can resolve file-file conflicts
             src_a_root, src_a_relpath = self.files[proj_rel_path]
-            self.file_conflicts.append(
-                MergeConflict(
-                    dst=proj_rel_path,
-                    src_a=os.path.join(src_a_root, src_a_relpath),
-                    src_b=os.path.join(root, rel_path),
-                )
-            )
+            self.file_conflicts.append(MergeConflict(
+                dst=proj_rel_path,
+                src_a=os.path.join(src_a_root, src_a_relpath),
+                src_b=os.path.join(root, rel_path)))
         else:
             # Otherwise register this file to be linked.
             self.files[proj_rel_path] = (root, rel_path)
 
-    def visit_symlinked_file(self, root, rel_path, depth):
-        # Treat symlinked files as ordinary files (without "dereferencing")
-        self.visit_file(root, rel_path, depth)
-
     def set_projection(self, projection):
         self.projection = os.path.normpath(projection)
 
         # Todo, is this how to check in general for empty projection?
-        if self.projection == ".":
-            self.projection = ""
+        if self.projection == '.':
+            self.projection = ''
             return
 
         # If there is a projection, we'll also create the directories
         # it consists of, and check whether that's causing conflicts.
-        path = ""
+        path = ''
         for part in self.projection.split(os.sep):
             path = os.path.join(path, part)
             if path not in self.files:
-                self.directories[path] = ("<projection>", path)
+                self.directories[path] = ('<projection>', path)
             else:
                 # Can't create a dir where a file is.
                 src_a_root, src_a_relpath = self.files[path]
-                self.fatal_conflicts.append(
-                    MergeConflict(
-                        dst=path,
-                        src_a=os.path.join(src_a_root, src_a_relpath),
-                        src_b=os.path.join("<projection>", path),
-                    )
-                )
+                self.fatal_conflicts.append(MergeConflict(
+                    dst=path,
+                    src_a=os.path.join(src_a_root, src_a_relpath),
+                    src_b=os.path.join('<projection>', path)))
 
 
-class DestinationMergeVisitor(BaseDirectoryVisitor):
+class DestinationMergeVisitor(object):
     """DestinatinoMergeVisitor takes a SourceMergeVisitor
     and:
 
@@ -212,7 +200,6 @@ class DestinationMergeVisitor(BaseDirectoryVisitor):
     in the target prefix will never be merged with
     directories in the sources directories.
     """
-
     def __init__(self, source_merge_visitor):
         self.src = source_merge_visitor
 
@@ -221,11 +208,10 @@ def before_visit_dir(self, root, rel_path, depth):
         # and don't traverse deeper
         if rel_path in self.src.files:
             src_a_root, src_a_relpath = self.src.files[rel_path]
-            self.src.fatal_conflicts.append(
-                MergeConflict(
-                    rel_path, os.path.join(src_a_root, src_a_relpath), os.path.join(root, rel_path)
-                )
-            )
+            self.src.fatal_conflicts.append(MergeConflict(
+                rel_path,
+                os.path.join(src_a_root, src_a_relpath),
+                os.path.join(root, rel_path)))
             return False
 
         # If destination dir was also a src dir, remove the mkdir
@@ -238,6 +224,9 @@ def before_visit_dir(self, root, rel_path, depth):
         # don't descend into it.
         return False
 
+    def after_visit_dir(self, root, rel_path, depth):
+        pass
+
     def before_visit_symlinked_dir(self, root, rel_path, depth):
         """
         Symlinked directories in the destination prefix should
@@ -247,44 +236,39 @@ def before_visit_symlinked_dir(self, root, rel_path, depth):
         # Always conflict
         if rel_path in self.src.directories:
             src_a_root, src_a_relpath = self.src.directories[rel_path]
-            self.src.fatal_conflicts.append(
-                MergeConflict(
-                    rel_path, os.path.join(src_a_root, src_a_relpath), os.path.join(root, rel_path)
-                )
-            )
+            self.src.fatal_conflicts.append(MergeConflict(
+                rel_path,
+                os.path.join(src_a_root, src_a_relpath),
+                os.path.join(root, rel_path)))
 
         if rel_path in self.src.files:
             src_a_root, src_a_relpath = self.src.files[rel_path]
-            self.src.fatal_conflicts.append(
-                MergeConflict(
-                    rel_path, os.path.join(src_a_root, src_a_relpath), os.path.join(root, rel_path)
-                )
-            )
+            self.src.fatal_conflicts.append(MergeConflict(
+                rel_path,
+                os.path.join(src_a_root, src_a_relpath),
+                os.path.join(root, rel_path)))
 
         # Never descend into symlinked target dirs.
         return False
 
+    def after_visit_symlinked_dir(self, root, rel_path, depth):
+        pass
+
     def visit_file(self, root, rel_path, depth):
         # Can't merge a file if target already exists
         if rel_path in self.src.directories:
             src_a_root, src_a_relpath = self.src.directories[rel_path]
-            self.src.fatal_conflicts.append(
-                MergeConflict(
-                    rel_path, os.path.join(src_a_root, src_a_relpath), os.path.join(root, rel_path)
-                )
-            )
+            self.src.fatal_conflicts.append(MergeConflict(
+                rel_path,
+                os.path.join(src_a_root, src_a_relpath),
+                os.path.join(root, rel_path)))
 
         elif rel_path in self.src.files:
             src_a_root, src_a_relpath = self.src.files[rel_path]
-            self.src.fatal_conflicts.append(
-                MergeConflict(
-                    rel_path, os.path.join(src_a_root, src_a_relpath), os.path.join(root, rel_path)
-                )
-            )
-
-    def visit_symlinked_file(self, root, rel_path, depth):
-        # Treat symlinked files as ordinary files (without "dereferencing")
-        self.visit_file(root, rel_path, depth)
+            self.src.fatal_conflicts.append(MergeConflict(
+                rel_path,
+                os.path.join(src_a_root, src_a_relpath),
+                os.path.join(root, rel_path)))
 
 
 class LinkTree(object):
@@ -297,31 +281,30 @@ class LinkTree(object):
     symlinked to, to prevent the source directory from ever being
     modified.
     """
-
     def __init__(self, source_root):
         if not os.path.exists(source_root):
             raise IOError("No such file or directory: '%s'", source_root)
 
         self._root = source_root
 
-    def find_conflict(self, dest_root, ignore=None, ignore_file_conflicts=False):
+    def find_conflict(self, dest_root, ignore=None,
+                      ignore_file_conflicts=False):
         """Returns the first file in dest that conflicts with src"""
         ignore = ignore or (lambda x: False)
         conflicts = self.find_dir_conflicts(dest_root, ignore)
 
         if not ignore_file_conflicts:
             conflicts.extend(
-                dst
-                for src, dst in self.get_file_map(dest_root, ignore).items()
-                if os.path.exists(dst)
-            )
+                dst for src, dst
+                in self.get_file_map(dest_root, ignore).items()
+                if os.path.exists(dst))
 
         if conflicts:
             return conflicts[0]
 
     def find_dir_conflicts(self, dest_root, ignore):
         conflicts = []
-        kwargs = {"follow_nonexisting": False, "ignore": ignore}
+        kwargs = {'follow_nonexisting': False, 'ignore': ignore}
         for src, dest in traverse_tree(self._root, dest_root, **kwargs):
             if os.path.isdir(src):
                 if os.path.exists(dest) and not os.path.isdir(dest):
@@ -332,7 +315,7 @@ def find_dir_conflicts(self, dest_root, ignore):
 
     def get_file_map(self, dest_root, ignore):
         merge_map = {}
-        kwargs = {"follow_nonexisting": True, "ignore": ignore}
+        kwargs = {'follow_nonexisting': True, 'ignore': ignore}
         for src, dest in traverse_tree(self._root, dest_root, **kwargs):
             if not os.path.isdir(src):
                 merge_map[src] = dest
@@ -354,7 +337,8 @@ def merge_directories(self, dest_root, ignore):
                     touch(marker)
 
     def unmerge_directories(self, dest_root, ignore):
-        for src, dest in traverse_tree(self._root, dest_root, ignore=ignore, order="post"):
+        for src, dest in traverse_tree(
+                self._root, dest_root, ignore=ignore, order='post'):
             if os.path.isdir(src):
                 if not os.path.exists(dest):
                     continue
@@ -370,7 +354,8 @@ def unmerge_directories(self, dest_root, ignore):
                 if os.path.exists(marker):
                     os.remove(marker)
 
-    def merge(self, dest_root, ignore_conflicts=False, ignore=None, link=symlink, relative=False):
+    def merge(self, dest_root, ignore_conflicts=False, ignore=None,
+              link=symlink, relative=False):
         """Link all files in src into dest, creating directories
            if necessary.
 
@@ -392,8 +377,7 @@ def merge(self, dest_root, ignore_conflicts=False, ignore=None, link=symlink, re
             ignore = lambda x: False
 
         conflict = self.find_conflict(
-            dest_root, ignore=ignore, ignore_file_conflicts=ignore_conflicts
-        )
+            dest_root, ignore=ignore, ignore_file_conflicts=ignore_conflicts)
         if conflict:
             raise SingleMergeConflictError(conflict)
 
@@ -432,7 +416,8 @@ class MergeConflictError(Exception):
 
 class SingleMergeConflictError(MergeConflictError):
     def __init__(self, path):
-        super(MergeConflictError, self).__init__("Package merge blocked by file: %s" % path)
+        super(MergeConflictError, self).__init__(
+            "Package merge blocked by file: %s" % path)
 
 
 class MergeConflictSummary(MergeConflictError):
@@ -445,6 +430,5 @@ def __init__(self, conflicts):
         # show the first 3 merge conflicts.
         for conflict in conflicts[:3]:
             msg += "\n    `{0}` and `{1}` both project to `{2}`".format(
-                conflict.src_a, conflict.src_b, conflict.dst
-            )
+                conflict.src_a, conflict.src_b, conflict.dst)
         super(MergeConflictSummary, self).__init__(msg)