feat(ng-dev/pr): support auto-merging pull requests once pending status checks pass

ng-dev/pr/common/validation/assert-passing-ci.ts

@@ -31,10 +31,11 @@ class Validation extends PullRequestValidation {
     if (statuses.find((status) => status.name === 'lint') === undefined) {
       throw this._createError(
         'Pull request is missing expected status checks. Check the pull request for pending workflows',
+        false,
       );
     }
     if (combinedStatus === PullRequestStatus.PENDING) {
-      throw this._createError('Pull request has pending status checks.');
+      throw this._createError('Pull request has pending status checks.', false);
     }
     if (combinedStatus === PullRequestStatus.FAILING) {
       throw this._createError('Pull request has failing status checks.');

ng-dev/pr/common/validation/validate-pull-request.ts

@@ -10,7 +10,9 @@ import {parseCommitMessage} from '../../../commit-message/parse.js';
 import {ActiveReleaseTrains} from '../../../release/versioning/active-release-trains.js';
 import {NgDevConfig, GithubConfig} from '../../../utils/config.js';
 import {PullRequestConfig, PullRequestValidationConfig} from '../../config/index.js';
-import {PullRequestFromGithub} from '../fetch-pull-request.js';
+import {fetchPullRequestFromGithub, PullRequestFromGithub} from '../fetch-pull-request.js';
+import {Log} from '../../../utils/logging.js';
+import {Spinner} from '../../../utils/spinner.js';
 import {PullRequestTarget} from '../targeting/target-label.js';
 import {changesAllowForTargetLabelValidation} from './assert-allowed-target-label.js';
 import {breakingChangeInfoValidation} from './assert-breaking-change-info.js';
@@ -25,20 +27,18 @@ import {pendingStateValidation} from './assert-pending.js';
 import {signedClaValidation} from './assert-signed-cla.js';
 import {PullRequestValidationFailure} from './validation-failure.js';
 import {AuthenticatedGitClient} from '../../../utils/git/authenticated-git-client.js';
+import {setTimeout} from 'node:timers/promises';
 
 /**
  * Runs all valiations that the given pull request is valid, returning a list of all failing
  * validations.
  *
  * Active release trains may be available for additional checks or not.
  */
-export async function assertValidPullRequest(
+async function runValidations(
   pullRequest: PullRequestFromGithub,
   validationConfig: PullRequestValidationConfig,
-  ngDevConfig: NgDevConfig<{
-    pullRequest: PullRequestConfig;
-    github: GithubConfig;
-  }>,
+  ngDevConfig: NgDevConfig<{pullRequest: PullRequestConfig; github: GithubConfig}>,
   activeReleaseTrains: ActiveReleaseTrains | null,
   target: PullRequestTarget,
   gitClient: AuthenticatedGitClient,
@@ -48,7 +48,7 @@ export async function assertValidPullRequest(
     return parseCommitMessage(n.commit.message);
   });
 
-  const validationResults = [
+  const validationPromises = [
     minimumReviewsValidation.run(validationConfig, pullRequest),
     completedReviewsValidation.run(validationConfig, pullRequest),
     mergeReadyValidation.run(validationConfig, pullRequest),
@@ -67,7 +67,7 @@ export async function assertValidPullRequest(
   ];
 
   if (activeReleaseTrains !== null) {
-    validationResults.push(
+    validationPromises.push(
       changesAllowForTargetLabelValidation.run(
         validationConfig,
         commitsInPr,
@@ -80,11 +80,75 @@ export async function assertValidPullRequest(
     );
   }
 
-  return await Promise.all(validationResults).then((results) => {
-    return results.filter(
-      <(result: null | PullRequestValidationFailure) => result is PullRequestValidationFailure>(
-        ((result) => result !== null)
-      ),
+  const results = await Promise.all(validationPromises);
+  return results.filter((result): result is PullRequestValidationFailure => result !== null);
+}
+
+export async function assertValidPullRequest(
+  originalPullRequest: PullRequestFromGithub,
+  validationConfig: PullRequestValidationConfig,
+  ngDevConfig: NgDevConfig<{
+    pullRequest: PullRequestConfig;
+    github: GithubConfig;
+  }>,
+  activeReleaseTrains: ActiveReleaseTrains | null,
+  target: PullRequestTarget,
+  gitClient: AuthenticatedGitClient,
+): Promise<PullRequestValidationFailure[]> {
+  let pullRequest = originalPullRequest;
+  let spinner: Spinner | undefined;
+  const maxAttempts = 60;
+  let attempts = 0;
+
+  while (true) {
+    const failures = await runValidations(
+      pullRequest,
+      validationConfig,
+      ngDevConfig,
+      activeReleaseTrains,
+      target,
+      gitClient,
     );
-  });
+
+    const finalFailures = failures.filter((f) => f.isFinal);
+    const nonFinalFailures = failures.filter((f) => !f.isFinal);
+
+    const shouldWaitForPending =
+      nonFinalFailures.length > 0 && finalFailures.length === 0 && validationConfig.waitIfPending;
+
+    if (!shouldWaitForPending) {
+      if (spinner) {
+        spinner.complete();
+      }
+      return failures;
+    }
+
+    if (attempts >= maxAttempts) {
+      if (spinner) {
+        spinner.complete();
+      }
+      Log.error(
+        `Timed out waiting for non-final validations to complete after ${maxAttempts} minutes.`,
+      );
+      return failures;
+    }
+
+    const names = nonFinalFailures.map((f) => f.validationName).join(', ');
+    const verb = nonFinalFailures.length === 1 ? 'is' : 'are';
+    const spinnerText = `[${names}] ${verb} not final. Waiting for completion (attempt ${attempts + 1}/${maxAttempts})...`;
+
+    if (!spinner) {
+      spinner = new Spinner(spinnerText);
+    } else {
+      spinner.update(spinnerText);
+    }
+
+    await setTimeout(60000); // Wait 1 minute
+    const freshPr = await fetchPullRequestFromGithub(gitClient, originalPullRequest.number);
+    if (!freshPr) {
+      throw new Error('Failed to re-fetch pull request data');
+    }
+    pullRequest = freshPr;
+    attempts++;
+  }
 }

ng-dev/pr/common/validation/validation-config.ts

@@ -33,7 +33,10 @@ export function createPullRequestValidationConfig(
 }
 
 /** Type describing a helper function for validations to create a validation failure. */
-export type PullRequestValidationErrorCreateFn = (message: string) => PullRequestValidationFailure;
+export type PullRequestValidationErrorCreateFn = (
+  message: string,
+  isFinal?: boolean,
+) => PullRequestValidationFailure;
 
 /**
  * Base class for pull request validations, providing helpers for the validation errors,
@@ -62,7 +65,8 @@ export function createPullRequestValidation<T extends PullRequestValidation>(
       if (validationConfig[name]) {
         const validation = new (getValidationCtor())(
           name,
-          (message) => new PullRequestValidationFailure(message, name, canBeForceIgnored),
+          (message, isFinal = true) =>
+            new PullRequestValidationFailure(message, name, canBeForceIgnored, isFinal),
         );
         try {
           await validation.assert(...args);

ng-dev/pr/common/validation/validation-failure.ts

@@ -17,5 +17,7 @@ export class PullRequestValidationFailure {
     public readonly validationName: keyof PullRequestValidationConfig,
     /** Validation config name for the failure. */
     public readonly canBeForceIgnored: boolean,
+    /** Whether the failure is final and will not change without action from a human. */
+    public readonly isFinal: boolean = true,
   ) {}
 }

ng-dev/pr/config/index.ts

@@ -90,4 +90,5 @@ export function assertValidPullRequestConfig<T extends NgDevConfig>(
 
 export interface PullRequestValidationConfig {
   [key: `assert${string}`]: boolean;
+  waitIfPending?: boolean;
 }

ng-dev/pr/merge/cli.ts

@@ -18,6 +18,7 @@ export interface MergeCommandOptions {
   forceManualBranches: boolean;
   dryRun: boolean;
   ignorePendingReviews: boolean;
+  waitForValidations: boolean;
 }
 
 /** Builds the command. */
@@ -45,6 +46,11 @@ async function builder(argv: Argv) {
       type: 'boolean',
       default: false,
       description: 'Bypass the check for pending reviews on the pull request',
+    })
+    .option('wait-for-validations' as 'waitForValidations', {
+      type: 'boolean',
+      default: false,
+      description: 'Wait for pending validations to complete before merging.',
     });
 }
 
@@ -55,8 +61,15 @@ async function handler({
   forceManualBranches,
   dryRun,
   ignorePendingReviews,
+  waitForValidations,
 }: Arguments<MergeCommandOptions>) {
-  await mergePullRequest(pr, {branchPrompt, forceManualBranches, dryRun, ignorePendingReviews});
+  await mergePullRequest(pr, {
+    branchPrompt,
+    forceManualBranches,
+    dryRun,
+    ignorePendingReviews,
+    waitForValidations,
+  });
 }
 
 /** yargs command module describing the command. */

ng-dev/pr/merge/merge-tool.ts

@@ -39,13 +39,15 @@ export interface PullRequestMergeFlags {
   forceManualBranches: boolean;
   dryRun: boolean;
   ignorePendingReviews: boolean;
+  waitForValidations: boolean;
 }
 
 const defaultPullRequestMergeFlags: PullRequestMergeFlags = {
   branchPrompt: true,
   forceManualBranches: false,
   dryRun: false,
   ignorePendingReviews: false,
+  waitForValidations: false,
 };
 
 /**
@@ -82,6 +84,7 @@ export class MergeTool {
     const validationConfig = createPullRequestValidationConfig({
       ...this.config.pullRequest.validators,
       ...partialValidationConfig,
+      waitIfPending: this.flags.waitForValidations,
     });
 
     if (this.git.hasUncommittedChanges()) {