PR review labeler: extract PR number from commit ID (#8627)

.github/workflows/pr-label-on-approved.yml

@@ -1,25 +1,43 @@
 name: PR review labeler
 on:
   workflow_run:
-    workflows: ["PR review listener"]
+    workflows: ["PR review listener"]   # must match the other workflow's name
     types: [completed]
 
 jobs:
   label:
-    if: ${{ github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.pull_requests[0] }}
-    name: "Set label"
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    runs-on: ubuntu-latest
     permissions:
       contents: read
       issues: write
       pull-requests: write
-    runs-on: ubuntu-latest
+
     steps:
-      - name: Extract PR number
+      - name: Resolve PR number from head_sha
         id: pr
-        run: |
-          echo "number=${{ github.event.workflow_run.pull_requests[0].number }}" >> "$GITHUB_OUTPUT"
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const { owner, repo } = context.repo;
+            const sha = context.payload.workflow_run.head_sha;
+
+            const { data: prs } = await github.rest.repos.listPullRequestsAssociatedWithCommit({
+              owner, repo, commit_sha: sha
+            });
+
+            if (!prs.length) {
+              core.setFailed(`❌ No PR found for commit ${sha}`);
+              return;
+            }
+
+            // Pick an open PR if possible
+            const pr = prs.find(p => p.state === 'open') || prs[0];
+            core.info(`Using PR #${pr.number}`);
+            core.setOutput('number', String(pr.number));
 
       - name: Label when approved
+        if: ${{ success() }}
         uses: j-fulbright/label-when-approved-action@v1.2
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
@@ -27,5 +45,4 @@ jobs:
           require_committers_approval: 'true'
           remove_label_when_approval_missing: 'true'
           comment: '✅ This PR has been reviewed and approved — all set for merge!'
-          # action runs on workflow_run, so pass PR number explicitly
           pullRequestNumber: ${{ steps.pr.outputs.number }}