feat(dev-infra): automatically add labels to release PRs (#40016)

Automatically add provided labels to PRs created for release.

PR Close #40016

.ng-dev/release.ts

@@ -32,7 +32,5 @@ export const release: ReleaseConfig = {
   generateReleaseNotesForHead: async () => {
     exec('yarn -s gulp changelog', {cwd: join(__dirname, '../')});
   },
-  // The `comp: *` labels will be automatically added by PullApprove and the targeting label will
-  // be added by the release tooling, only `action: merge` must be manually included to the list.
   releasePrLabels: ['comp: build & ci', 'action: merge', 'PullApprove: disable'],
 };

dev-infra/ng-dev.js

@@ -5676,6 +5676,10 @@ class ReleaseAction {
             const { fork, branchName } = yield this._pushHeadToFork(proposedForkBranchName, true);
             const { data } = yield this.git.github.pulls.create(Object.assign(Object.assign({}, this.git.remoteParams), { head: `${fork.owner}:${branchName}`, base: targetBranch, body,
                 title }));
+            // Add labels to the newly created PR if provided in the configuration.
+            if (this.config.releasePrLabels !== undefined) {
+                yield this.git.github.issues.addLabels(Object.assign(Object.assign({}, this.git.remoteParams), { issue_number: data.number, labels: this.config.releasePrLabels }));
+            }
             info(green(`  ✓   Created pull request #${data.number} in ${repoSlug}.`));
             return {
                 id: data.number,

dev-infra/release/config/index.ts

@@ -34,6 +34,8 @@ export interface ReleaseConfig {
    */
   // TODO: Remove this in favor of a canonical changelog format across the Angular organization.
   extractReleaseNotesPattern?: (version: semver.SemVer) => RegExp;
+  /** The list of github labels to add to the release PRs. */
+  releasePrLabels?: string[];
 }
 
 /** Configuration for releases in the dev-infra configuration. */

dev-infra/release/publish/actions.ts

@@ -282,6 +282,15 @@ export abstract class ReleaseAction {
       title,
     });
 
+    // Add labels to the newly created PR if provided in the configuration.
+    if (this.config.releasePrLabels !== undefined) {
+      await this.git.github.issues.addLabels({
+        ...this.git.remoteParams,
+        issue_number: data.number,
+        labels: this.config.releasePrLabels,
+      });
+    }
+
     info(green(`  ✓   Created pull request #${data.number} in ${repoSlug}.`));
     return {
       id: data.number,