ci: cache PHPStan results

Author: justlevine

.github/workflows/reusable-php-static-analysis.yml

@@ -25,11 +25,11 @@ jobs:
   # - Checks out the repository.
   # - Sets up PHP.
   # - Logs debug information.
-  # - Configures caching for PHP static analysis scans.
-  # - Validates the composer.json file.
   # - Installs Composer dependencies.
+  # - Configures caching for PHP static analysis scans.
   # - Make Composer packages available globally.
   # - Runs PHPStan static analysis (with Pull Request annotations).
+  # - Saves the PHPStan result cache.
   # - Ensures version-controlled files are not modified or deleted.
   phpstan:
     name: Run PHP static analysis
@@ -62,12 +62,6 @@ jobs:
         id: get-date
         run: echo "date=$(/bin/date -u --date='last Mon' "+%F")" >> "$GITHUB_OUTPUT"
 
-      - name: Cache PHP Static Analysis scan cache
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
-        with:
-          path: .cache/phpcompat.json
-          key: ${{ runner.os }}-date-${{ steps.get-date.outputs.date }}-php-${{ inputs.php-version }}-phpcompat-cache-${{ hashFiles('**/composer.json', 'phpcompat.xml.dist') }}
-
       # Since Composer dependencies are installed using `composer update` and no lock file is in version control,
       # passing a custom cache suffix ensures that the cache is flushed at least once per week.
       - name: Install Composer dependencies
@@ -78,9 +72,24 @@ jobs:
       - name: Make Composer packages available globally
         run: echo "${PWD}/vendor/bin" >> "$GITHUB_PATH"
 
+      - name: Cache PHP Static Analysis scan cache
+        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: .cache # This is defined in the base.neon file.
+          key: "phpstan-result-cache-${{ github.run_id }}"
+          restore-keys: |
+            phpstan-result-cache-
+
       - name: Run PHP static analysis tests
         id: phpstan
-        run: phpstan analyse -vv --error-format=checkstyle |cs2pr
+        run: phpstan analyse -vv --error-format=checkstyle | cs2pr
+
+      - name: "Save result cache"
+        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        if: ${{ !cancelled() }}
+        with:
+          path: .cache
+          key: "phpstan-result-cache-${{ github.run_id }}"
 
       - name: Ensure version-controlled files are not modified or deleted
         run: git diff --exit-code

tests/phpstan/base.neon

@@ -5,6 +5,9 @@
 # https://phpstan.org/config-reference
 
 parameters:
+  # Cache is stored locally, so it's available for CI.
+  tmpDir: ../../.cache
+
   # What directories and files should be scanned.
   paths:
     - ../../src