fix(pr): ensure PR update after branch commit (#18839)

Co-authored-by: Rhys Arkins <rhys@arkins.net>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>
Closes #17388

lib/workers/repository/update/branch/index.spec.ts

@@ -1955,5 +1955,59 @@ describe('workers/repository/update/branch/index', () => {
         result: 'done',
       });
     });
+
+    it('continues branch, skips automerge if there are artifact errors', async () => {
+      jest.spyOn(getUpdated, 'getUpdatedPackageFiles').mockResolvedValueOnce({
+        updatedPackageFiles: [{}],
+        artifactErrors: [{}],
+      } as PackageFilesResult);
+      npmPostExtract.getAdditionalFiles.mockResolvedValueOnce({
+        artifactErrors: [],
+        updatedArtifacts: [],
+      });
+      git.branchExists.mockReturnValueOnce(true);
+      git.isBranchModified.mockResolvedValueOnce(true);
+      git.getBranchCommit.mockReturnValueOnce('123test');
+      platform.findPr.mockResolvedValueOnce({ sha: '123test' } as any);
+      const res = await branchWorker.processBranch(config);
+      expect(automerge.tryBranchAutomerge).not.toHaveBeenCalled();
+      expect(prAutomerge.checkAutoMerge).not.toHaveBeenCalled();
+      expect(res).toEqual({
+        branchExists: true,
+        commitSha: '123test',
+        prNo: undefined,
+        result: 'done',
+        updatesVerified: true,
+      });
+    });
+
+    it('continues to update PR, if branch got updated, even when prCreation!==immediate', async () => {
+      git.branchExists.mockReturnValueOnce(true);
+      git.isBranchModified.mockResolvedValueOnce(false);
+      git.getBranchCommit.mockReturnValueOnce('123test');
+      npmPostExtract.getAdditionalFiles.mockResolvedValueOnce({
+        artifactErrors: [],
+        updatedArtifacts: [partial<FileChange>({})],
+      } as WriteExistingFilesResult);
+      platform.getBranchPr.mockResolvedValueOnce({
+        state: 'open',
+      } as Pr);
+      jest.spyOn(getUpdated, 'getUpdatedPackageFiles').mockResolvedValueOnce({
+        updatedPackageFiles: [{}],
+      } as PackageFilesResult);
+      const inconfig = {
+        ...config,
+        prCreation: 'not-pending',
+      } as BranchConfig;
+      expect(await branchWorker.processBranch(inconfig)).toEqual({
+        branchExists: true,
+        updatesVerified: true,
+        prNo: undefined,
+        result: 'done',
+        commitSha: '123test',
+      });
+      expect(automerge.tryBranchAutomerge).not.toHaveBeenCalled();
+      expect(prWorker.ensurePr).toHaveBeenCalledTimes(1);
+    });
   });
 });

lib/workers/repository/update/branch/index.ts

@@ -553,9 +553,11 @@ export async function processBranch(
     await setStability(config);
     await setConfidence(config);
 
-    // break if we pushed a new commit because status check are pretty sure pending but maybe not reported yet
+    // new commit means status check are pretty sure pending but maybe not reported yet
+    // if PR has not been created + new commit + prCreation !== immediate skip
     // but do not break when there are artifact errors
     if (
+      !branchPr &&
       !config.artifactErrors?.length &&
       !userRebaseRequested &&
       commitSha &&
@@ -565,14 +567,15 @@ export async function processBranch(
       return {
         branchExists: true,
         updatesVerified,
-        prNo: branchPr?.number,
         result: BranchResult.Pending,
         commitSha,
       };
     }
 
     // Try to automerge branch and finish if successful, but only if branch already existed before this run
-    if (branchExists || config.ignoreTests) {
+    // skip if we have a non-immediate pr and there is an existing PR,
+    // we want to update the PR and skip the Auto merge since status checks aren't done yet
+    if (!config.artifactErrors?.length && (!commitSha || config.ignoreTests)) {
       const mergeStatus = await tryBranchAutomerge(config);
       logger.debug(`mergeStatus=${mergeStatus}`);
       if (mergeStatus === 'automerged') {
@@ -811,13 +814,17 @@ export async function processBranch(
         }
       } else if (config.automerge) {
         logger.debug('PR is configured for automerge');
-        const prAutomergeResult = await checkAutoMerge(pr, config);
-        if (prAutomergeResult?.automerged) {
-          return {
-            branchExists,
-            result: BranchResult.Automerged,
-            commitSha,
-          };
+        // skip automerge if there is a new commit since status checks aren't done yet
+        if (!commitSha || config.ignoreTests) {
+          logger.debug('checking auto-merge');
+          const prAutomergeResult = await checkAutoMerge(pr, config);
+          if (prAutomergeResult?.automerged) {
+            return {
+              branchExists,
+              result: BranchResult.Automerged,
+              commitSha,
+            };
+          }
         }
       } else {
         logger.debug('PR is not configured for automerge');