[3.12] Convert change detection to a Python script (GH-129627) (#130370)

Co-authored-by: Adam Turner <[email protected]>
Co-authored-by: Hugo van Kemenade <[email protected]>
Co-authored-by: Sviatoslav Sydorenko (Святослав Сидоренко) <[email protected]>

Author: 3 people

.github/workflows/build.yml

@@ -22,32 +22,32 @@ env:
   FORCE_COLOR: 1
 
 jobs:
-  check_source:
+  build-context:
     name: Change detection
     # To use boolean outputs from this job, parse them as JSON.
     # Here's some examples:
     #
-    #   if: fromJSON(needs.check_source.outputs.run-docs)
+    #   if: fromJSON(needs.build-context.outputs.run-docs)
     #
     #   ${{
-    #        fromJSON(needs.check_source.outputs.run_tests)
+    #        fromJSON(needs.build-context.outputs.run-tests)
     #        && 'truthy-branch'
     #        || 'falsy-branch'
     #   }}
     #
-    uses: ./.github/workflows/reusable-change-detection.yml
+    uses: ./.github/workflows/reusable-context.yml
 
   check-docs:
     name: Docs
-    needs: check_source
-    if: fromJSON(needs.check_source.outputs.run-docs)
+    needs: build-context
+    if: fromJSON(needs.build-context.outputs.run-docs)
     uses: ./.github/workflows/reusable-docs.yml
 
   check_abi:
     name: 'Check if the ABI has changed'
     runs-on: ubuntu-22.04
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     steps:
       - uses: actions/checkout@v4
         with:
@@ -96,8 +96,8 @@ jobs:
     container:
       image: ghcr.io/python/autoconf:2024.10.16.11360930377
     timeout-minutes: 60
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     steps:
       - name: Install Git
         run: |
@@ -137,8 +137,8 @@ jobs:
     # reproducible: to get the same tools versions (autoconf, aclocal, ...)
     runs-on: ubuntu-24.04
     timeout-minutes: 60
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     steps:
       - uses: actions/checkout@v4
         with:
@@ -153,7 +153,7 @@ jobs:
         with:
           path: config.cache
           # Include env.pythonLocation in key to avoid changes in environment when setup-python updates Python
-          key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.check_source.outputs.config_hash }}-${{ env.pythonLocation }}
+          key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.build-context.outputs.config-hash }}-${{ env.pythonLocation }}
       - name: Install dependencies
         run: sudo ./.github/workflows/posix-deps-apt.sh
       - name: Add ccache to PATH
@@ -199,8 +199,8 @@ jobs:
     name: >-
       Windows
       ${{ fromJSON(matrix.free-threading) && '(free-threading)' || '' }}
-    needs: check_source
-    if: fromJSON(needs.check_source.outputs.run_tests)
+    needs: build-context
+    if: fromJSON(needs.build-context.outputs.run-tests)
     strategy:
       matrix:
         arch:
@@ -218,8 +218,8 @@ jobs:
   build_windows_msi:
     name: >-  # ${{ '' } is a hack to nest jobs under the same sidebar category
       Windows MSI${{ '' }}
-    needs: check_source
-    if: fromJSON(needs.check_source.outputs.run-win-msi)
+    needs: build-context
+    if: fromJSON(needs.build-context.outputs.run-windows-msi)
     strategy:
       matrix:
         arch:
@@ -234,8 +234,8 @@ jobs:
     name: >-
       macOS
       ${{ fromJSON(matrix.free-threading) && '(free-threading)' || '' }}
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     strategy:
       fail-fast: false
       matrix:
@@ -260,32 +260,32 @@ jobs:
           free-threading: true
     uses: ./.github/workflows/reusable-macos.yml
     with:
-      config_hash: ${{ needs.check_source.outputs.config_hash }}
+      config_hash: ${{ needs.build-context.outputs.config-hash }}
       free-threading: ${{ matrix.free-threading }}
       os: ${{ matrix.os }}
 
   build_ubuntu:
     name: >-
       Ubuntu
       ${{ fromJSON(matrix.free-threading) && '(free-threading)' || '' }}
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     strategy:
       matrix:
         free-threading:
         - false
         # - true
     uses: ./.github/workflows/reusable-ubuntu.yml
     with:
-      config_hash: ${{ needs.check_source.outputs.config_hash }}
+      config_hash: ${{ needs.build-context.outputs.config-hash }}
       free-threading: ${{ matrix.free-threading }}
 
   build_ubuntu_ssltests:
     name: 'Ubuntu SSL tests with OpenSSL'
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     strategy:
       fail-fast: false
       matrix:
@@ -306,7 +306,7 @@ jobs:
       uses: actions/cache@v4
       with:
         path: config.cache
-        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.check_source.outputs.config_hash }}
+        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.build-context.outputs.config-hash }}
     - name: Register gcc problem matcher
       run: echo "::add-matcher::.github/problem-matchers/gcc.json"
     - name: Install dependencies
@@ -345,8 +345,8 @@ jobs:
     name: "Hypothesis tests on Ubuntu"
     runs-on: ubuntu-24.04
     timeout-minutes: 60
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true' && needs.check_source.outputs.run_hypothesis == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     env:
       OPENSSL_VER: 3.0.15
       PYTHONSTRICTEXTENSIONBUILD: 1
@@ -393,7 +393,7 @@ jobs:
       uses: actions/cache@v4
       with:
         path: ${{ env.CPYTHON_BUILDDIR }}/config.cache
-        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.check_source.outputs.config_hash }}
+        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.build-context.outputs.config-hash }}
     - name: Configure CPython out-of-tree
       working-directory: ${{ env.CPYTHON_BUILDDIR }}
       run: |
@@ -460,8 +460,8 @@ jobs:
     name: 'Address sanitizer'
     runs-on: ubuntu-22.04
     timeout-minutes: 60
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     strategy:
       matrix:
         os: [ubuntu-24.04]
@@ -479,7 +479,7 @@ jobs:
       uses: actions/cache@v4
       with:
         path: config.cache
-        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.check_source.outputs.config_hash }}
+        key: ${{ github.job }}-${{ env.IMAGE_OS_VERSION }}-${{ needs.build-context.outputs.config-hash }}
     - name: Register gcc problem matcher
       run: echo "::add-matcher::.github/problem-matchers/gcc.json"
     - name: Install dependencies
@@ -523,23 +523,23 @@ jobs:
     name: >-
       Thread sanitizer
       ${{ fromJSON(matrix.free-threading) && '(free-threading)' || '' }}
-    needs: check_source
-    if: needs.check_source.outputs.run_tests == 'true'
+    needs: build-context
+    if: needs.build-context.outputs.run-tests == 'true'
     strategy:
       matrix:
         free-threading:
         - false
     uses: ./.github/workflows/reusable-tsan.yml
     with:
-      config_hash: ${{ needs.check_source.outputs.config_hash }}
+      config_hash: ${{ needs.build-context.outputs.config-hash }}
       free-threading: ${{ matrix.free-threading }}
 
   all-required-green:  # This job does nothing and is only used for the branch protection
     name: All required checks pass
     if: always()
 
     needs:
-    - check_source  # Transitive dependency, needed to access `run_tests` value
+    - build-context  # Transitive dependency, needed to access `run-tests` value
     - check-docs
     - check_autoconf_regen
     - check_generated_files
@@ -564,14 +564,14 @@ jobs:
           test_hypothesis,
         allowed-skips: >-
           ${{
-            !fromJSON(needs.check_source.outputs.run-docs)
+            !fromJSON(needs.build-context.outputs.run-docs)
             && '
             check-docs,
             '
             || ''
           }}
           ${{
-            needs.check_source.outputs.run_tests != 'true'
+            needs.build-context.outputs.run-tests != 'true'
             && '
             check_autoconf_regen,
             check_generated_files,
@@ -581,12 +581,6 @@ jobs:
             build_windows,
             build_asan,
             build_tsan,
-            '
-            || ''
-          }}
-          ${{
-            !fromJSON(needs.check_source.outputs.run_hypothesis)
-            && '
             test_hypothesis,
             '
             || ''

.github/workflows/reusable-context.yml

@@ -0,0 +1,100 @@
+name: Reusable build context
+
+on:  # yamllint disable-line rule:truthy
+  workflow_call:
+    outputs:
+      # Every referenced step MUST always set its output variable,
+      # either via ``Tools/build/compute-changes.py`` or in this workflow file.
+      # Boolean outputs (generally prefixed ``run-``) can then later be used
+      # safely through the following idiom in job conditionals and other
+      # expressions. Here's some examples:
+      #
+      #   if: fromJSON(needs.build-context.outputs.run-tests)
+      #
+      #   ${{
+      #        fromJSON(needs.build-context.outputs.run-tests)
+      #        && 'truthy-branch'
+      #        || 'falsy-branch'
+      #   }}
+      #
+      config-hash:
+        description: Config hash value for use in cache keys
+        value: ${{ jobs.compute-changes.outputs.config-hash }}  # str
+      run-docs:
+        description: Whether to build the docs
+        value: ${{ jobs.compute-changes.outputs.run-docs }}  # bool
+      run-tests:
+        description: Whether to run the regular tests
+        value: ${{ jobs.compute-changes.outputs.run-tests  }}  # bool
+      run-windows-msi:
+        description: Whether to run the MSI installer smoke tests
+        value: ${{ jobs.compute-changes.outputs.run-windows-msi }}  # bool
+      run-ci-fuzz:
+        description: Whether to run the CIFuzz job
+        value: ${{ jobs.compute-changes.outputs.run-ci-fuzz }}  # bool
+
+jobs:
+  compute-changes:
+    name: Create context from changed files
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    outputs:
+      config-hash: ${{ steps.config-hash.outputs.hash }}
+      run-ci-fuzz: ${{ steps.changes.outputs.run-ci-fuzz }}
+      run-docs: ${{ steps.changes.outputs.run-docs }}
+      run-tests: ${{ steps.changes.outputs.run-tests }}
+      run-windows-msi: ${{ steps.changes.outputs.run-windows-msi }}
+    steps:
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: "3"
+
+    - run: >-
+        echo '${{ github.event_name }}'
+
+    - uses: actions/checkout@v4
+      with:
+        persist-credentials: false
+        ref: >-
+          ${{
+            github.event_name == 'pull_request'
+            && github.event.pull_request.head.sha
+            || ''
+          }}
+
+    # Adapted from https://github.com/actions/checkout/issues/520#issuecomment-1167205721
+    - name: Fetch commits to get branch diff
+      if: github.event_name == 'pull_request'
+      run: |
+        set -eux
+
+        # Fetch enough history to find a common ancestor commit (aka merge-base):
+        git fetch origin "${refspec_pr}" --depth=$(( commits + 1 )) \
+          --no-tags --prune --no-recurse-submodules
+
+        # This should get the oldest commit in the local fetched history (which may not be the commit the PR branched from):
+        COMMON_ANCESTOR=$( git rev-list --first-parent --max-parents=0 --max-count=1 "${branch_pr}" )
+        DATE=$( git log --date=iso8601 --format=%cd "${COMMON_ANCESTOR}" )
+
+        # Get all commits since that commit date from the base branch (eg: main):
+        git fetch origin "${refspec_base}" --shallow-since="${DATE}" \
+          --no-tags --prune --no-recurse-submodules
+      env:
+        branch_pr: 'origin/${{ github.event.pull_request.head.ref }}'
+        commits: ${{ github.event.pull_request.commits }}
+        refspec_base: '+${{ github.event.pull_request.base.sha }}:remotes/origin/${{ github.event.pull_request.base.ref }}'
+        refspec_pr: '+${{ github.event.pull_request.head.sha }}:remotes/origin/${{ github.event.pull_request.head.ref }}'
+
+    # We only want to run tests on PRs when related files are changed,
+    # or when someone triggers a manual workflow run.
+    - name: Compute changed files
+      id: changes
+      run: python Tools/build/compute-changes.py
+      env:
+        GITHUB_DEFAULT_BRANCH: ${{ github.event.repository.default_branch }}
+
+    - name: Compute hash for config cache key
+      id: config-hash
+      run: |
+        echo "hash=${{ hashFiles('configure', 'configure.ac', '.github/workflows/build.yml') }}" >> "$GITHUB_OUTPUT"