fix(circleci-orb): rebase script not working on windows

Fixes that the rebase script is not working on Windows by
using `spawnSync` with `shell: true`. Like we do in the ng-dev
git client (which we cannot use here).

Also fixes that the rebease command fails if there is no user
configured. We always set a user as part of rebasing. The user
may be overriden later by other scripts- like the publish snapshots
script.

circleci-orb/BUILD.bazel

@@ -2,7 +2,7 @@ load("@build_bazel_rules_nodejs//:index.bzl", "nodejs_binary")
 
 ORB_NAME = "angular/dev-infra"
 
-ORB_VERSION = "1.0.0"
+ORB_VERSION = "1.0.1"
 
 nodejs_binary(
     name = "pack_orb_script",

circleci-orb/scripts/rebase-pr-on-target-branch/helpers.ts

@@ -6,21 +6,37 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {execSync as execSync_} from 'child_process';
+import {spawnSync} from 'child_process';
 import {getRefFromBranchList} from './ref-branch-list';
 
-/** Synchronously executes the command, suppressing errors as empty string outputs. */
-export function exec(command: string): string {
-  try {
-    return execSync_(command, {stdio: 'pipe', encoding: 'utf8'}).trim();
-  } catch (err: unknown) {
-    return '';
+/**
+ * Synchronously executes the Git command.
+ *
+ * @throws {Error} Errors will be thrown on non-successful commands.
+ */
+export function execGit(args: string[]): string {
+  const cmd = `git ${args.join(' ')}`;
+  const proc = spawnSync('git', args, {shell: true, stdio: 'pipe', encoding: 'utf8'});
+
+  if (proc.error !== undefined) {
+    console.error(proc.error);
+    throw new Error(`Unexpected error while executing: ${cmd}`);
   }
+
+  if (proc.status !== 0) {
+    console.error(`Failed executing: ${cmd}.`);
+    console.error(`Status Code: ${proc.status}`);
+    console.error(`Stdout: ${proc.stdout}`);
+    console.error(`Stderr: ${proc.stdout}`);
+    throw new Error(`Unexpected error while executing: ${cmd}`);
+  }
+
+  return proc.stdout.trim();
 }
 
 /**
- * Get the list of branches which contain the provided sha, sorted in descending
- * order by committerdate.
+ * Get the list of branches which contain the provided sha, sorted in
+ * descending order by committerdate.
  *
  * example:
  *   upstream/main
@@ -29,25 +45,25 @@ export function exec(command: string): string {
  *   upstream/1.1.x
  */
 export function getBranchListForSha(sha: string, remote: string) {
-  return exec(`git branch -r '${remote}/*' --sort=-committerdate --contains ${sha}`);
+  return execGit(['branch', '-r', `${remote}/*`, '--sort=-committerdate', '--contains', sha]);
 }
 
 /** Get the common ancestor sha of the two provided shas. */
 export function getCommonAncestorSha(sha1: string, sha2: string) {
-  return exec(`git merge-base ${sha1} ${sha2}`);
+  return execGit(['merge-base', sha1, sha2]);
 }
 
 /** * Adds the remote to git, if it doesn't already exist. */
 export function addAndFetchRemote(owner: string, name: string) {
   const remoteName = `${owner}_${name}`;
-  exec(`git remote add ${remoteName} https://github.com/${owner}/${name}.git`);
-  exec(`git fetch ${remoteName}`);
+  execGit(['remote', 'add', remoteName, `https://github.com/${owner}/${name}.git`]);
+  execGit(['fetch', remoteName]);
   return remoteName;
 }
 
 /** Get the full sha of the ref provided. */
 export function getShaFromRef(ref: string) {
-  return exec(`git rev-parse ${ref}`);
+  return execGit(['rev-parse', ref]);
 }
 
 /** Get the ref and latest shas for the provided sha on a specific remote. */

circleci-orb/scripts/rebase-pr-on-target-branch/index.ts

@@ -8,7 +8,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {exec, getCommonAncestorSha, lookupSha} from './helpers';
+import {execGit, getCommonAncestorSha, lookupSha} from './helpers';
 
 // Parameter variables.
 const baseRevision = process.env.CIRCLE_GIT_BASE_REVISION!;
@@ -32,6 +32,10 @@ if (!process.env.CIRCLE_PR_NUMBER) {
 
 /** Rebase on the latest commit for the targeted branch. */
 (async () => {
+  // Rebasing requires a Git user set.
+  execGit(['config', 'user.email', '[email protected]']);
+  execGit(['config', 'user.name', 'Angular Robot']);
+
   const base = lookupSha(baseRevision, baseRepoOwner, baseRepoName, primaryBranchName);
   const head = lookupSha(headRevision, headRepoOwner, headRepoName, primaryBranchName);
   const commonAncestorSha = getCommonAncestorSha(base.sha, head.sha);
@@ -46,14 +50,20 @@ if (!process.env.CIRCLE_PR_NUMBER) {
   console.log();
 
   // Get the count of commits between the latest commit from origin and the common ancestor SHA.
-  const commitCount = exec(`git rev-list --count origin/${base.ref}...${commonAncestorSha}`);
+  const commitCount = execGit(['rev-list', '--count', `origin/${base.ref}...${commonAncestorSha}`]);
   console.log(`Checking ${commitCount} commits for changes in the CircleCI config file.`);
 
   // Check if the files changed between the latest commit from origin and the common ancestor SHA
   // includes the CircleCI config.
-  const circleCIConfigChanged = exec(
-    `git diff --name-only origin/${base.ref} ${commonAncestorSha} -- .circleci/config.yml`,
-  );
+  const circleCIConfigChanged = execGit([
+    'diff',
+    '--name-only',
+    `origin/${base.ref}`,
+    commonAncestorSha,
+    '--',
+    '.circleci/config.yml',
+  ]);
+
   if (!!circleCIConfigChanged) {
     throw Error(`
         CircleCI config on ${base.ref} has been modified since commit
@@ -77,7 +87,7 @@ if (!process.env.CIRCLE_PR_NUMBER) {
   console.log();
 
   // Rebase the PR.
-  exec(`git rebase origin/${base.ref}`);
+  execGit(['rebase', `origin/${base.ref}`]);
   console.log(`Rebased current branch onto ${base.ref}.`);
 })().catch((err: unknown) => {
   console.error('Failed to rebase on top of target branch.');

circleci-orb/scripts/rebase-pr-on-target-branch/ref-branch-list.ts

@@ -20,7 +20,7 @@ const semverRegex = /^(\d+)\.(\d+)\.x$/;
  * likely correct branch will be the first one encountered in the list.
  */
 export function getRefFromBranchList(gitOutput: string, primaryBranchName: string): string {
-  const branches = gitOutput.split('\n').map((b) => b.split('/').slice(1).join('').trim());
+  const branches = gitOutput.split(/\r?\n/g).map((b) => b.split('/').slice(1).join('').trim());
 
   return branches.sort((a: string, b: string) => {
     if (a === primaryBranchName) {