chore(workflows): Fix benchmark workflow (#119)

Author: devsjc

.github/workflows/bench.yml

@@ -42,65 +42,70 @@ jobs:
             ${{ steps.gopaths.outputs.path }}/include
           key: ${{ runner.os }}-gobin-${{ hashfiles('Makefile') }}
 
-      - name: Generate code
-        run: make gen
-
-      - name: Get benchmark filename for base branch
-        id: base-benchfile
-        if: github.event_name == 'pull_request'
+      - name: Get benchmark filenames and cache keys
+        id: benchfiles
         run: |
-          BASE_BENCHFILE="${{ github.event.pull_request.base.ref }}"
-          echo "name=bench-${BASE_BENCHFILE////-}.txt" >> "$GITHUB_OUTPUT"
+          if [[ "${{ github.event_name }}" == "pull_request" ]]; then
+            BASE_REF="${{ github.event.pull_request.base.ref }}"
+          else
+            BASE_REF="main"
+          fi
+          SAFE_BASE_REF="${BASE_REF////-}"
+          echo "base-filename=bench-${SAFE_BASE_REF}.txt" >> "$GITHUB_OUTPUT"
+          echo "base-cache-key=${{ runner.os }}-benchmark-${SAFE_BASE_REF}" >> "$GITHUB_OUTPUT"
+
+          HEAD_REF="${{ github.head_ref || github.ref_name }}"
+          SAFE_HEAD_REF="${HEAD_REF////-}"
+          echo "head-filename=bench-${SAFE_HEAD_REF}.txt" >> "$GITHUB_OUTPUT"
+          echo "head-cache-key=${{ runner.os }}-benchmark-${SAFE_HEAD_REF}" >> "$GITHUB_OUTPUT"
 
-      - name: Get benchmark filename for head branch
-        id: head-benchfile
-        run: |
-          HEAD_BENCHFILE="${{ github.head_ref || github.ref_name }}"
-          echo "name=bench-${HEAD_BENCHFILE////-}.txt" >> "$GITHUB_OUTPUT"
+      - name: Generate code
+        run: make gen
 
       - name: Restore PR base branch benchmarks
         uses: actions/cache/restore@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
-        id: cache-base-bench
+        id: restore-base-bench
         if: github.event_name == 'pull_request'
         with:
-          path: ${{ steps.base-benchfile.outputs.name }}
-          key: ${{ runner.os }}-bench-${{ steps.base-benchfile.outputs.name }}
+          path: ${{ steps.benchfiles.outputs.base-filename }}
+          key: ${{ steps.benchfiles.outputs.base-cache-key }}
 
       - name: Run benchmarks
-        env:
-          BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
         run: |
-          make bench > ${{ steps.head-benchfile.outputs.name }}
-          cat ${{ steps.head-benchfile.outputs.name }}
+          make bench > ${{ steps.benchfiles.outputs.head-filename }}
+          cat ${{ steps.benchfiles.outputs.head-filename }}
 
       - name: Delete old benchmark caches
         if: github.event_name != 'pull_request'
         continue-on-error: true
         run: |
-          gh cache delete ${{ runner.os }}-bench-main.txt
+          gh cache delete "${{ steps.benchfiles.outputs.head-cache-key }}"
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Cache benchmark results
         uses: actions/cache/save@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         if: github.event_name != 'pull_request'
         with:
-          path: ${{ steps.head-benchfile.outputs.name }}
-          key: ${{ runner.os }}-bench-${{ steps.head-benchfile.outputs.name }}
+          path: ${{ steps.benchfiles.outputs.head-filename }}
+          key: ${{ steps.benchfiles.outputs.head-cache-key }}
 
       - name: Compare benchmarks
         id: bench-diff
         if: github.event_name == 'pull_request' && steps.cache-base-bench.outputs.cache-hit == 'true'
         run: |
-          go run golang.org/x/perf/cmd/benchstat@latest ${{ steps.base-benchfile.outputs.name }} ${{ steps.head-benchfile.outputs.name }} > bench-diff.txt
+          go run golang.org/x/perf/cmd/benchstat@latest \
+            ${{ steps.benchfiles.outputs.base-filename }} \
+            ${{ steps.benchfiles.outputs.head-filename }} > bench-diff.txt
           cat bench-diff.txt
           echo 'summary<<EOF' >> $GITHUB_OUTPUT
           cat bench-diff.txt >> $GITHUB_OUTPUT
           echo 'EOF' >> $GITHUB_OUTPUT
 
       - name: Write results to markdown file
         env:
-          FILENAME: ${{ steps.head-benchfile.outputs.name }}
+          FILENAME: ${{ steps.benchfiles.outputs.head-filename }}
+          BENCH_DIFF: ${{ steps.bench-diff.outputs.summary }}
         run: |
           {
             echo "### Benchmark Results"
@@ -111,21 +116,17 @@ jobs:
             cat "$FILENAME"
             echo '```'
             echo "</details>"
-          } > bench-comment.md
 
-      - name: Write benchmark diff to markdown file
-        if: github.event_name == 'pull_request' && steps.cache-base-bench.outputs.cache-hit == 'true'
-        run: |
-          BENCH_DIFF="${{ steps.bench-diff.outputs.summary }}"
-          cat <<EOF >> bench-comment.md
-
-          <details><summary>Benchmark vs base branch</summary>
-
-          \`\`\`
-          $BENCH_DIFF
-          \`\`\`
-          </details>
-          EOF
+            if [ -n "$BENCH_DIFF" ]; then
+              echo ""
+              echo "<details open><summary>Benchmark vs base branch</summary>"
+              echo ""
+              echo '```'
+              echo "$BENCH_DIFF"
+              echo '```'
+              echo "</details>"
+            fi
+          } > bench-comment.md
 
       - name: Upload benchmark results
         if: github.event_name == 'pull_request'