fix: handle renamed branch refs for signed commits

__test__/github-helper.unit.test.ts

@@ -0,0 +1,82 @@
+jest.mock('../src/octokit-client', () => ({
+  Octokit: class {},
+  retryOptions: {},
+  throttleOptions: {}
+}))
+jest.mock('@octokit/request-error', () => ({
+  RequestError: class extends Error {}
+}))
+jest.mock('p-limit', () => ({
+  __esModule: true,
+  default: () => (fn: () => unknown) => fn()
+}))
+
+import {GitHubHelper} from '../src/github-helper'
+import type {Commit, GitCommandManager} from '../src/git-command-manager'
+
+describe('GitHubHelper signed commit refs', () => {
+  const createHelper = (returnedBranchName: string) => {
+    const octokit = {
+      rest: {
+        repos: {
+          getBranch: jest
+            .fn()
+            .mockResolvedValue({data: {name: returnedBranchName}})
+        },
+        git: {
+          updateRef: jest.fn().mockResolvedValue({}),
+          createRef: jest.fn().mockResolvedValue({})
+        }
+      }
+    }
+    const helper = new GitHubHelper('github.com', '')
+    Object.defineProperty(helper, 'octokit', {value: octokit})
+    return {helper, octokit}
+  }
+
+  const git = {} as GitCommandManager
+  const baseCommit = {sha: 'base-sha', tree: 'tree-sha'} as Commit
+
+  test('creates a ref when getBranch redirects to a renamed branch', async () => {
+    const {helper, octokit} = createHelper('renamed-topic')
+
+    await helper.pushSignedCommits(
+      git,
+      [],
+      baseCommit,
+      '',
+      'owner/repo',
+      'topic'
+    )
+
+    expect(octokit.rest.git.createRef).toHaveBeenCalledWith({
+      owner: 'owner',
+      repo: 'repo',
+      sha: 'base-sha',
+      ref: 'refs/heads/topic'
+    })
+    expect(octokit.rest.git.updateRef).not.toHaveBeenCalled()
+  })
+
+  test('updates the ref when getBranch returns the requested branch', async () => {
+    const {helper, octokit} = createHelper('topic')
+
+    await helper.pushSignedCommits(
+      git,
+      [],
+      baseCommit,
+      '',
+      'owner/repo',
+      'topic'
+    )
+
+    expect(octokit.rest.git.updateRef).toHaveBeenCalledWith({
+      owner: 'owner',
+      repo: 'repo',
+      sha: 'base-sha',
+      ref: 'heads/topic',
+      force: true
+    })
+    expect(octokit.rest.git.createRef).not.toHaveBeenCalled()
+  })
+})

src/github-helper.ts

@@ -441,7 +441,7 @@ export class GitHubHelper {
         branch: branch
       })
       .then(
-        () => true,
+        ({data}) => data.name === branch,
         () => false
       )