fix(check-merge-safety): expand error type handling

src/helpers/check-merge-safety.ts

@@ -130,7 +130,7 @@ const getDiff = async (compareBase: DiffRefs, compareHead: DiffRefs, basehead: s
     core.info(`Failed to fetch diff: ${(err as GithubError).message} Status: ${(err as GithubError).status}`);
 
     // diff too large error
-    if ((err as GithubError)?.status === 406) {
+    if ((err as GithubError)?.status === 406 || (err as GithubError)?.message.includes('diff is taking too long to generate')) {
       core.info(`Attempting to generate diff using local git command`);
       if (compareBase.repo?.html_url) {
         changedFileNames = await getDiffUsingGitCommand(compareBase.repo?.html_url, compareBase.sha, compareHead.sha);

test/helpers/check-merge-safety.test.ts

@@ -62,7 +62,7 @@ type MockGithubRequests = (
   filesOutOfDate: string[],
   changedFilesOnPr: string[],
   branch?: string,
-  error?: { status: number; message?: string } | null
+  error?: { status: number | string; message?: string } | null
 ) => void;
 const mockGithubRequests: MockGithubRequests = (filesOutOfDate, changedFilesOnPr, branch = branchName, error = null) => {
   (octokit.repos.compareCommitsWithBasehead as unknown as Mocktokit).mockImplementation(async ({ basehead }) => {
@@ -136,7 +136,7 @@ describe('checkMergeSafety', () => {
     expect(core.setFailed).toHaveBeenCalledWith('This branch has one or more outdated projects. Please update with main.');
   });
 
-  it('should allow merge when branch is only out of date for an unchanged project - diff too large error', async () => {
+  it('should allow merge when branch is only out of date for an unchanged project - diff too large error status', async () => {
     const filesOutOfDate = ['packages/package-2/src/another-file.ts'];
     const changedFilesOnPr = ['packages/package-1/src/some-file.ts'];
     mockGithubRequests(filesOutOfDate, changedFilesOnPr, branchName, { status: 406 });
@@ -157,6 +157,30 @@ describe('checkMergeSafety', () => {
     expect(core.setFailed).not.toHaveBeenCalled();
   });
 
+  it('should allow merge when branch is only out of date for an unchanged project - diff too large error message', async () => {
+    const filesOutOfDate = ['packages/package-2/src/another-file.ts'];
+    const changedFilesOnPr = ['packages/package-1/src/some-file.ts'];
+    mockGithubRequests(filesOutOfDate, changedFilesOnPr, branchName, {
+      status: 'not_available',
+      message: 'yadda yadda diff is taking too long to generate yadda yadda'
+    });
+    mockGitInteractions(filesOutOfDate, changedFilesOnPr);
+
+    await checkMergeSafety({
+      paths: allProjectPaths,
+      ...context.repo
+    });
+    expect(setCommitStatus).toHaveBeenCalledWith({
+      sha,
+      state: 'success',
+      context: 'Merge Safety',
+      description: 'Branch username:some-branch-name is safe to merge!',
+      repo: 'repo',
+      owner: 'owner'
+    });
+    expect(core.setFailed).not.toHaveBeenCalled();
+  });
+
   it('should prevent merge when branch is out of date for a changed project - diff too large error', async () => {
     const filesOutOfDate = ['packages/package-1/src/another-file.ts'];
     const changedFilesOnPr = ['packages/package-1/src/some-file.ts'];