Merge pull request #29540 from overleaf/gs-jenkins-pr-build-tags-remote

Check if Jenkins checkout revision exists on remote

GitOrigin-RevId: cb110f5479836ccbfd1a62f501210dee6606d37e

services/web/Jenkinsfile

@@ -30,9 +30,21 @@ pipeline {
         script {
           def relevantCommitHash
           if (env.CHANGE_BRANCH) {
-            echo "PR build detected. Jenkins checked out a merge commit: ${GIT_COMMIT}"
-            relevantCommitHash = sh(script: 'git rev-parse HEAD^1', returnStdout: true).trim()
-            echo "Found actual branch commit: ${relevantCommitHash}"
+            def commitExistsOnRemote = sh(script: "git branch --remotes --contains ${GIT_COMMIT}", returnStdout: true).trim()
+            if (commitExistsOnRemote) {
+              echo "PR build detected, but commit exists on remote. Using ${GIT_COMMIT}"
+              relevantCommitHash = "${GIT_COMMIT}"
+            } else {
+              def parentCommits = sh(script: 'git rev-parse HEAD^@', returnStdout: true).trim().split('\n')
+              if (parentCommits.size() >= 2) {
+                echo "PR build detected. Jenkins checked out a merge commit: ${GIT_COMMIT} (parents: ${parentCommits.join(', ')})"
+                relevantCommitHash = parentCommits[0]
+                echo "Using first parent (branch commit): ${relevantCommitHash}"
+              } else {
+                echo "WARN: PR build detected, but ${GIT_COMMIT} is neither a merge commit, nor does it exist on the remote."
+                relevantCommitHash = "${GIT_COMMIT}"
+              }
+            }
           } else {
             echo "Branch build detected. Using commit: ${GIT_COMMIT}"
             relevantCommitHash = "${GIT_COMMIT}"