fix: call setFailed when push fails with existing PR (review feedback)

Co-Authored-By: Niels Swimberghe <3382717+Swimburger@users.noreply.github.com>

Author: devin-ai-integration[bot]

dist/index.js

@@ -39678,6 +39678,7 @@ async function pushWithFallback(branchName, owner, repo, octokit) {
                 `- Merge or close this PR so the next run creates a fresh one, or\n` +
                 `- Manually rebase this branch on \`${github.context.ref.replace("refs/heads/", "")}\` and re-run the workflow.`,
         });
+        core.setFailed(`Failed to push changes to '${branchName}' due to conflicts. A comment has been left on PR #${existingPRNumber}.`);
     }
     else {
         core.setFailed(`Failed to push changes to '${branchName}' and no existing PR was found to comment on.`);

src/sync.test.ts

@@ -327,6 +327,13 @@ describe("updateFromSourceSpec", () => {
             const commentCall = mockIssuesCreateComment.mock.calls[0][0];
             expect(commentCall.body).toContain("Sync failed");
             expect(commentCall.body).toContain("merge conflicts");
+
+            // Action should still fail (not silently succeed)
+            expect(state.setFailedCalls).toEqual(
+                expect.arrayContaining([
+                    expect.stringContaining("conflicts"),
+                ]),
+            );
         });
 
         it("should call setFailed when push fails and no existing PR to comment on", async () => {

src/sync.ts

@@ -564,6 +564,9 @@ async function pushWithFallback(
                 `- Merge or close this PR so the next run creates a fresh one, or\n` +
                 `- Manually rebase this branch on \`${github.context.ref.replace("refs/heads/", "")}\` and re-run the workflow.`,
         });
+        core.setFailed(
+            `Failed to push changes to '${branchName}' due to conflicts. A comment has been left on PR #${existingPRNumber}.`,
+        );
     } else {
         core.setFailed(
             `Failed to push changes to '${branchName}' and no existing PR was found to comment on.`,