ci: cache fixtures

Only generate fixtures if any grammar from any parser or the parser
generation itself has changed.

.github/workflows/build.yml

@@ -156,16 +156,21 @@ jobs:
     - name: Build CLI
       run: $BUILD_CMD build --release --target=${{ matrix.target }} --features=${CLI_FEATURES}
 
-    - name: Fetch fixtures
-      if: ${{ !matrix.cli-only && inputs.run_test }} # Don't fetch fixtures for only CLI building targets
-      run: script/fetch-fixtures
+    - run: script/fetch-fixtures
+
+    - uses: actions/cache@v4
+      id: cache_fixtures
+      with:
+        path: test/fixtures/grammars
+        key: fixtures-${{ join(matrix.*, '_') }}-${{ hashFiles('test/fixtures/grammars/*/**/src/*.c', 'cli/src/generate/**',
+          'script/generate-fixtures*', '.github/workflows/builds.yml') }}
 
     - name: Generate fixtures
-      if: ${{ !matrix.cli-only && inputs.run_test }} # Can't natively run CLI on Github runner's host
+      if: ${{ !matrix.cli-only && inputs.run_test && steps.cache_fixtures.outputs.cache-hit != 'true' }} # Can't natively run CLI on Github runner's host
       run: script/generate-fixtures
 
     - name: Generate WASM fixtures
-      if: ${{ !matrix.cli-only && !matrix.use-cross && inputs.run_test }} # See comment for the "Build wasm library" step
+      if: ${{ !matrix.cli-only && !matrix.use-cross && inputs.run_test && steps.cache_fixtures.outputs.cache-hit != 'true' }} # See comment for the "Build wasm library" step
       run: script/generate-fixtures-wasm
 
     - name: Run main tests

.github/workflows/sanitize.yml

@@ -27,10 +27,15 @@ jobs:
     - name: Build CLI
       run: cargo build --release
 
-    - name: Fetch fixtures
-      run: script/fetch-fixtures
-
-    - name: Generate fixtures
+    - run: script/fetch-fixtures
+    - uses: actions/cache@v4
+      id: cache_fixtures
+      with:
+        path: test/fixtures/grammars
+        key: fixtures-sanitize-${{ hashFiles('test/fixtures/grammars/*/**/src/*.c', 'cli/src/generate/**',
+          'script/generate-fixtures', '.github/workflows/sanitize.yml') }}
+
+    - if: ${{ steps.cache_fixtures.outputs.cache-hit != 'true' }}
       run: script/generate-fixtures
 
     - name: Run main tests with undefined behaviour sanitizer (UBSAN)