bug(scripts): Fix two issues with create-patch-pr.js.

.github/workflows/release-patch-1-create-pr.yml

@@ -75,15 +75,20 @@ jobs:
           GH_TOKEN: '${{ steps.generate_token.outputs.token }}'
         continue-on-error: true
         run: |
-          # Capture output and display it in logs using tee
-          {
-            node scripts/releasing/create-patch-pr.js --commit=${{ github.event.inputs.commit }} --channel=${{ github.event.inputs.channel }} --dry-run=${{ github.event.inputs.dry_run }}
-            echo "EXIT_CODE=$?" >> "$GITHUB_OUTPUT"
-          } 2>&1 | tee >(
-            echo "LOG_CONTENT<<EOF" >> "$GITHUB_ENV"
-            cat >> "$GITHUB_ENV"
-            echo "EOF" >> "$GITHUB_ENV"
-          )
+          # Use a temporary file to store the log
+          LOG_FILE=$(mktemp)
+
+          # Run the script and tee the output to the log file
+          node scripts/releasing/create-patch-pr.js --commit=${{ github.event.inputs.commit }} --channel=${{ github.event.inputs.channel }} --dry-run=${{ github.event.inputs.dry_run }} 2>&1 | tee "${LOG_FILE}"
+
+          # Capture the exit code of the node script (the first command in the pipe)
+          EXIT_CODE=${PIPESTATUS[0]}
+          echo "EXIT_CODE=${EXIT_CODE}" >> "$GITHUB_OUTPUT"
+
+          # Store the log content in an environment variable for the comment step
+          echo "LOG_CONTENT<<EOF" >> "$GITHUB_ENV"
+          cat "${LOG_FILE}" >> "$GITHUB_ENV"
+          echo "EOF" >> "$GITHUB_ENV"
 
       - name: 'Comment on Original PR'
         if: 'always() && inputs.original_pr'

scripts/releasing/create-patch-pr.js

@@ -7,10 +7,11 @@
  */
 
 import { execSync } from 'node:child_process';
+import { fileURLToPath } from 'node:url';
 import yargs from 'yargs';
 import { hideBin } from 'yargs/helpers';
 
-async function main() {
+export async function main() {
   const argv = await yargs(hideBin(process.argv))
     .option('commit', {
       alias: 'c',
@@ -134,7 +135,23 @@ async function main() {
       execSync(`git cherry-pick ${commit}`, { stdio: 'pipe' });
       console.log(`✅ Cherry-pick successful - no conflicts detected`);
     } catch (error) {
-      // Check if this is a cherry-pick conflict
+      const output = (error.stdout || '') + (error.stderr || '');
+
+      // Case 1: Commit is empty, which is not an error.
+      if (output.includes('The previous cherry-pick is now empty')) {
+        console.log(`✅ Commit ${commit} is empty and has been skipped.`);
+        process.exit(0);
+      }
+
+      // Case 2: Commit has already been applied.
+      if (output.match(/nothing to commit/)) {
+        console.log(
+          `✅ Commit ${commit} has already been applied to ${releaseBranch}. No patch needed.`,
+        );
+        process.exit(0);
+      }
+
+      // Case 3: It's a real error, check for merge conflicts.
       try {
         const status = execSync('git status --porcelain', { encoding: 'utf8' });
         const conflictFiles = status
@@ -164,11 +181,11 @@ async function main() {
           execSync(`git commit --no-edit`);
           console.log(`✅ Committed cherry-pick with conflict markers`);
         } else {
-          // Re-throw if it's not a conflict error
+          // It's not a conflict, so re-throw the original error.
           throw error;
         }
       } catch (_statusError) {
-        // Re-throw original error if we can't determine the status
+        // If `git status` fails, we can't determine the cause, so re-throw.
         throw error;
       }
     }
@@ -278,7 +295,11 @@ function getLatestReleaseInfo(channel) {
   }
 }
 
-main().catch((err) => {
-  console.error(err);
-  process.exit(1);
-});
+const isMain = process.argv[1] === fileURLToPath(import.meta.url);
+
+if (isMain) {
+  main().catch((err) => {
+    console.error(err);
+    process.exit(1);
+  });
+}

scripts/tests/create-patch-pr.test.js

@@ -0,0 +1,216 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, it, expect, beforeEach, afterEach } from 'vitest';
+
+// Mock the child_process module at the top level
+vi.mock('node:child_process', async (importOriginal) => {
+  const actual = await importOriginal();
+  return {
+    ...actual,
+    execSync: vi.fn(),
+  };
+});
+
+describe('create-patch-pr', () => {
+  const scriptPath = '../../scripts/releasing/create-patch-pr.js';
+  let originalArgv;
+  let execSyncMock;
+  let consoleLogSpy;
+  let consoleErrorSpy;
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  let processExitSpy;
+
+  // Helper to set up mocks with default "happy path" behavior
+  const setupMocks = (overrides = {}) => {
+    const defaultMocks = {
+      'get-release-version.js': () =>
+        JSON.stringify({
+          previousReleaseTag: 'v1.0.0',
+          releaseVersion: 'v1.0.1',
+        }),
+      'git ls-remote': () => {
+        throw new Error('exit code 1');
+      }, // Default: branches don't exist
+      'gh pr list': () => '', // Default: no existing PR
+      'git cherry-pick': () => '', // Default: success
+      'git push': () => '',
+      'git status': () => '',
+    };
+
+    const mocks = { ...defaultMocks, ...overrides };
+
+    execSyncMock.mockImplementation((command) => {
+      for (const key in mocks) {
+        if (command.includes(key)) {
+          return mocks[key]();
+        }
+      }
+      return ''; // Default success for other commands (checkout, config, etc.)
+    });
+  };
+
+  beforeEach(async () => {
+    vi.resetModules();
+    originalArgv = [...process.argv];
+    const cp = await import('node:child_process');
+    execSyncMock = cp.execSync;
+    vi.resetAllMocks();
+
+    consoleLogSpy = vi.spyOn(console, 'log').mockImplementation(() => {});
+    consoleErrorSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
+    processExitSpy = vi.spyOn(process, 'exit').mockImplementation((code) => {
+      throw new Error(`Process exited with code ${code}`);
+    });
+  });
+
+  afterEach(() => {
+    process.argv = originalArgv;
+    vi.restoreAllMocks();
+  });
+
+  async function runScript(args = []) {
+    process.argv = ['node', 'create-patch-pr.js', ...args];
+    const { main } = await import(scriptPath);
+    await main();
+  }
+
+  // --- TEST CASES ---
+
+  it('should complete successfully on the happy path', async () => {
+    setupMocks();
+    await runScript(['--commit', 'abcdef1', '--channel', 'stable']);
+
+    const prCommand = execSyncMock.mock.calls.find((call) =>
+      call[0].startsWith('gh pr create'),
+    );
+    expect(prCommand).toBeDefined();
+    expect(prCommand[0]).toContain('fix(patch): cherry-pick abcdef1');
+    expect(prCommand[0]).not.toContain('[CONFLICTS]');
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      '✅ Patch process completed successfully!',
+    );
+  });
+
+  it('should handle cherry-pick with merge conflicts', async () => {
+    setupMocks({
+      'git cherry-pick': () => {
+        throw new Error('Cherry-pick failed');
+      },
+      'git status': () => 'UU file1.js\nUU file2.js',
+    });
+
+    await runScript(['--commit', 'abcdef1', '--channel', 'stable']);
+
+    const prCommand = execSyncMock.mock.calls.find((call) =>
+      call[0].startsWith('gh pr create'),
+    );
+    expect(prCommand).toBeDefined();
+    expect(prCommand[0]).toContain('[CONFLICTS]');
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      expect.stringContaining('Cherry-pick has conflicts'),
+    );
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      '⚠️  Patch process completed with conflicts - manual resolution required!',
+    );
+  });
+
+  it('should exit gracefully if commit is already applied', async () => {
+    setupMocks({
+      'git cherry-pick': () => {
+        const error = new Error('Command failed');
+        error.stderr = 'nothing to commit, working tree clean';
+        throw error;
+      },
+    });
+
+    await expect(
+      runScript(['--commit', 'abcdef1', '--channel', 'stable']),
+    ).rejects.toThrow('Process exited with code 0');
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      expect.stringContaining('already been applied'),
+    );
+  });
+
+  it('should exit gracefully if commit is empty', async () => {
+    setupMocks({
+      'git cherry-pick': () => {
+        const error = new Error('Command failed');
+        error.stdout = 'The previous cherry-pick is now empty';
+        throw error;
+      },
+    });
+
+    await expect(
+      runScript(['--commit', 'abcdef1', '--channel', 'stable']),
+    ).rejects.toThrow('Process exited with code 0');
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      expect.stringContaining('is empty and has been skipped'),
+    );
+  });
+
+  it('should detect and report an existing PR', async () => {
+    setupMocks({
+      'git ls-remote': () => '', // Branches exist
+      'gh pr list': () =>
+        JSON.stringify({
+          number: 123,
+          url: 'https://github.com/owner/repo/pull/123',
+        }),
+    });
+
+    await runScript(['--commit', 'abcdef1', '--channel', 'stable']);
+
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      'Found existing PR #123: https://github.com/owner/repo/pull/123',
+    );
+    const prCreateCall = execSyncMock.mock.calls.find((call) =>
+      call[0].startsWith('gh pr create'),
+    );
+    expect(prCreateCall).toBeUndefined();
+  });
+
+  it('should log commands but not execute them in dry-run mode', async () => {
+    setupMocks();
+    await runScript([
+      '--commit',
+      'abcdef1',
+      '--channel',
+      'stable',
+      '--dry-run',
+    ]);
+
+    expect(consoleLogSpy).toHaveBeenCalledWith('Running in dry-run mode.');
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      expect.stringContaining('[DRY RUN] Would cherry-pick'),
+    );
+    const pushCall = execSyncMock.mock.calls.find((call) =>
+      call[0].startsWith('git push'),
+    );
+    expect(pushCall).toBeUndefined();
+  });
+
+  it('should provide manual instructions on permission failure', async () => {
+    setupMocks({
+      'git push': () => {
+        const error = new Error('Command failed');
+        error.message =
+          'GH013: refusing to allow a GitHub App to create or update workflow without the workflows permission.';
+        throw error;
+      },
+    });
+
+    await expect(
+      runScript(['--commit', 'abcdef1', '--channel', 'stable']),
+    ).rejects.toThrow('Process exited with code 1');
+    expect(consoleErrorSpy).toHaveBeenCalledWith(
+      expect.stringContaining('insufficient GitHub App permissions'),
+    );
+    expect(consoleLogSpy).toHaveBeenCalledWith(
+      expect.stringContaining('Please run these commands manually'),
+    );
+  });
+});