Reliable PR number relay for labeler workflow (#8628)

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

@@ -1,7 +1,7 @@
 name: PR review labeler
 on:
   workflow_run:
-    workflows: ["PR review listener"]   # must match the other workflow's name
+    workflows: ["PR review listener"]
     types: [completed]
 
 jobs:
@@ -14,30 +14,18 @@ jobs:
       pull-requests: write
 
     steps:
-      - name: Resolve PR number from head_sha
-        id: pr
-        uses: actions/github-script@v7
+      - name: Download PR number artifact from upstream run
+        uses: actions/download-artifact@v4
         with:
-          script: |
-            const { owner, repo } = context.repo;
-            const sha = context.payload.workflow_run.head_sha;
+          name: pr-number-${{ github.event.workflow_run.id }}   # same unique name
+          path: .
+          run-id: ${{ github.event.workflow_run.id }}           # ← CRITICAL: fetch from the upstream run
+          github-token: ${{ secrets.GITHUB_TOKEN }}
 
-            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));
+      - id: pr
+        run: echo "number=$(cat pr.txt)" >> $GITHUB_OUTPUT
 
       - name: Label when approved
-        if: ${{ success() }}
         uses: j-fulbright/label-when-approved-action@v1.2
         with:
           token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/pr-review-listener.yml

@@ -6,10 +6,15 @@ on:
 jobs:
   ping:
     if: ${{ github.event.review.state == 'approved' }}
-    name: "Listen"
+    runs-on: ubuntu-latest
     permissions:
       contents: read
-    runs-on: ubuntu-latest
     steps:
-      - run:
-          echo "Approved review detected for PR ${{ github.event.pull_request.number }}"
+      - name: Save PR number
+        run: echo "${{ github.event.pull_request.number }}" > pr.txt
+
+      - uses: actions/upload-artifact@v4
+        with:
+          # unique name: includes workflow run id
+          name: pr-number-${{ github.run_id }}
+          path: pr.txt