feat(dev-infra): add script for merging pull requests [patch version]

.ng-dev-config.ts

@@ -1,3 +1,7 @@
+import {exec} from 'shelljs';
+
+import {MergeConfig} from './dev-infra/pr/merge/config';
+
 // The configuration for `ng-dev commit-message` commands.
 const commitMessage = {
   'maxLength': 120,
@@ -72,15 +76,72 @@ const format = {
   'buildifier': true
 };
 
-// Github metadata information for `ng-dev` commands.
+/** Github metadata information for `ng-dev` commands. */
 const github = {
   owner: 'angular',
   name: 'angular',
 };
 
+/**
+ * Gets the name of the current patch branch. The patch branch is determined by
+ * looking for upstream branches that follow the format of `{major}.{minor}.x`.
+ */
+const getPatchBranchName = (): string => {
+  const branches =
+      exec(
+          `git ls-remote --heads https://github.com/${github.owner}/${github.name}.git`,
+          {silent: true})
+          .trim()
+          .split('\n');
+
+  for (let i = branches.length - 1; i >= 0; i--) {
+    const branchName = branches[i];
+    const matches = branchName.match(/refs\/heads\/([0-9]+\.[0-9]+\.x)/);
+    if (matches !== null) {
+      return matches[1];
+    }
+  }
+
+  throw Error('Could not determine patch branch name.');
+};
+
+// Configuration for the `ng-dev pr merge` command. The command can be used
+// for merging upstream pull requests into branches based on a PR target label.
+const merge = () => {
+  const patchBranch = getPatchBranchName();
+  const config: MergeConfig = {
+    githubApiMerge: false,
+    claSignedLabel: 'cla: yes',
+    mergeReadyLabel: /^PR action: merge(-assistance)?/,
+    commitMessageFixupLabel: 'commit message fixup',
+    labels: [
+      {
+        pattern: 'PR target: master-only',
+        branches: ['master'],
+      },
+      {
+        pattern: 'PR target: patch-only',
+        branches: [patchBranch],
+      },
+      {
+        pattern: 'PR target: master & patch',
+        branches: ['master', patchBranch],
+      },
+    ],
+    requiredBaseCommits: {
+      // PRs that target either `master` or the patch branch, need to be rebased
+      // on top of the latest commit message validation fix.
+      'master': '4341743b4a6d7e23c6f944aa9e34166b701369a1',
+      [patchBranch]: '2a53f471592f424538802907aca1f60f1177a86d'
+    },
+  };
+  return config;
+};
+
 // Export function to build ng-dev configuration object.
 module.exports = {
   commitMessage,
   format,
   github,
+  merge,
 };

dev-infra/pr/BUILD.bazel

@@ -2,20 +2,12 @@ load("@npm_bazel_typescript//:index.bzl", "ts_library")
 
 ts_library(
     name = "pr",
-    srcs = glob([
-        "*.ts",
-    ]),
+    srcs = ["cli.ts"],
     module_name = "@angular/dev-infra-private/pr",
     visibility = ["//dev-infra:__subpackages__"],
     deps = [
-        "//dev-infra/utils",
-        "@npm//@types/cli-progress",
-        "@npm//@types/node",
-        "@npm//@types/shelljs",
+        "//dev-infra/pr/discover-new-conflicts",
+        "//dev-infra/pr/merge",
         "@npm//@types/yargs",
-        "@npm//cli-progress",
-        "@npm//shelljs",
-        "@npm//typed-graphqlify",
-        "@npm//yargs",
     ],
 )

dev-infra/pr/cli.ts

@@ -7,39 +7,20 @@
  */
 
 import * as yargs from 'yargs';
-import {discoverNewConflictsForPr} from './discover-new-conflicts';
 
-/** A Date object 30 days ago. */
-const THIRTY_DAYS_AGO = (() => {
-  const date = new Date();
-  // Set the hours, minutes and seconds to 0 to only consider date.
-  date.setHours(0, 0, 0, 0);
-  // Set the date to 30 days in the past.
-  date.setDate(date.getDate() - 30);
-  return date;
-})();
+import {buildDiscoverNewConflictsCommand, handleDiscoverNewConflictsCommand} from './discover-new-conflicts/cli';
+import {buildMergeCommand, handleMergeCommand} from './merge/cli';
 
-/** Build the parser for the pr commands. */
+/** Build the parser for pull request commands. */
 export function buildPrParser(localYargs: yargs.Argv) {
-  return localYargs.help().strict().demandCommand().command(
-      'discover-new-conflicts <pr>',
-      'Check if a pending PR causes new conflicts for other pending PRs',
-      args => {
-        return args.option('date', {
-          description: 'Only consider PRs updated since provided date',
-          defaultDescription: '30 days ago',
-          coerce: Date.parse,
-          default: THIRTY_DAYS_AGO,
-        });
-      },
-      ({pr, date}) => {
-        // If a provided date is not able to be parsed, yargs provides it as NaN.
-        if (isNaN(date)) {
-          console.error('Unable to parse the value provided via --date flag');
-          process.exit(1);
-        }
-        discoverNewConflictsForPr(pr, date);
-      });
+  return localYargs.help()
+      .strict()
+      .demandCommand()
+      .command('merge <pr-number>', 'Merge pull requests', buildMergeCommand, handleMergeCommand)
+      .command(
+          'discover-new-conflicts <pr-number>',
+          'Check if a pending PR causes new conflicts for other pending PRs',
+          buildDiscoverNewConflictsCommand, handleDiscoverNewConflictsCommand)
 }
 
 if (require.main === module) {

dev-infra/pr/discover-new-conflicts/BUILD.bazel

@@ -0,0 +1,19 @@
+load("@npm_bazel_typescript//:index.bzl", "ts_library")
+
+ts_library(
+    name = "discover-new-conflicts",
+    srcs = [
+        "cli.ts",
+        "index.ts",
+    ],
+    module_name = "@angular/dev-infra-private/pr/discover-new-conflicts",
+    visibility = ["//dev-infra:__subpackages__"],
+    deps = [
+        "//dev-infra/utils",
+        "@npm//@types/cli-progress",
+        "@npm//@types/node",
+        "@npm//@types/shelljs",
+        "@npm//@types/yargs",
+        "@npm//typed-graphqlify",
+    ],
+)

dev-infra/pr/discover-new-conflicts/cli.ts

@@ -0,0 +1,33 @@
+import {Arguments, Argv} from 'yargs';
+
+import {discoverNewConflictsForPr} from './index';
+
+/** Builds the discover-new-conflicts pull request command. */
+export function buildDiscoverNewConflictsCommand(yargs: Argv) {
+  return yargs.option('date', {
+    description: 'Only consider PRs updated since provided date',
+    defaultDescription: '30 days ago',
+    coerce: Date.parse,
+    default: getThirtyDaysAgoDate,
+  });
+}
+
+/** Handles the discover-new-conflicts pull request command. */
+export async function handleDiscoverNewConflictsCommand({prNumber, date}: Arguments) {
+  // If a provided date is not able to be parsed, yargs provides it as NaN.
+  if (isNaN(date)) {
+    console.error('Unable to parse the value provided via --date flag');
+    process.exit(1);
+  }
+  await discoverNewConflictsForPr(prNumber, date);
+}
+
+/** Gets a date object 30 days ago from today. */
+function getThirtyDaysAgoDate(): Date {
+  const date = new Date();
+  // Set the hours, minutes and seconds to 0 to only consider date.
+  date.setHours(0, 0, 0, 0);
+  // Set the date to 30 days in the past.
+  date.setDate(date.getDate() - 30);
+  return date;
+}

dev-infra/pr/discover-new-conflicts.ts → dev-infra/pr/discover-new-conflicts/index.ts

@@ -9,10 +9,10 @@
 import {Bar} from 'cli-progress';
 import {types as graphQLTypes} from 'typed-graphqlify';
 
-import {getConfig, NgDevConfig} from '../utils/config';
-import {getCurrentBranch, hasLocalChanges} from '../utils/git';
-import {getPendingPrs} from '../utils/github';
-import {exec} from '../utils/shelljs';
+import {getConfig, NgDevConfig} from '../../utils/config';
+import {getCurrentBranch, hasLocalChanges} from '../../utils/git';
+import {getPendingPrs} from '../../utils/github';
+import {exec} from '../../utils/shelljs';
 
 
 /* GraphQL schema for the response body for each pending PR. */
@@ -67,8 +67,6 @@ export async function discoverNewConflictsForPr(
   const progressBar = new Bar({format: `[{bar}] ETA: {eta}s | {value}/{total}`});
   /* PRs which were found to be conflicting. */
   const conflicts: Array<PullRequest> = [];
-  /* String version of the updatedAfter value, for logging. */
-  const updatedAfterString = new Date(updatedAfter).toLocaleDateString();
 
   console.info(`Requesting pending PRs from Github`);
   /** List of PRs from github currently known as mergable. */

dev-infra/pr/merge/BUILD.bazel

@@ -0,0 +1,17 @@
+load("@npm_bazel_typescript//:index.bzl", "ts_library")
+
+ts_library(
+    name = "merge",
+    srcs = glob(["**/*.ts"]),
+    module_name = "@angular/dev-infra-private/pr/merge",
+    visibility = ["//dev-infra:__subpackages__"],
+    deps = [
+        "//dev-infra/commit-message",
+        "//dev-infra/utils",
+        "@npm//@octokit/rest",
+        "@npm//@types/inquirer",
+        "@npm//@types/node",
+        "@npm//@types/yargs",
+        "@npm//chalk",
+    ],
+)

dev-infra/pr/merge/cli.ts

@@ -0,0 +1,33 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import chalk from 'chalk';
+import {Arguments, Argv} from 'yargs';
+import {GITHUB_TOKEN_GENERATE_URL, mergePullRequest} from './index';
+
+/** Builds the options for the merge command. */
+export function buildMergeCommand(yargs: Argv) {
+  return yargs.help().strict().option('github-token', {
+    type: 'string',
+    description: 'Github token. If not set, token is retrieved from the environment variables.'
+  })
+}
+
+/** Handles the merge command. i.e. performs the merge of a specified pull request. */
+export async function handleMergeCommand(args: Arguments) {
+  const githubToken = args.githubToken || process.env.GITHUB_TOKEN || process.env.TOKEN;
+  if (!githubToken) {
+    console.error(
+        chalk.red('No Github token set. Please set the `GITHUB_TOKEN` environment variable.'));
+    console.error(chalk.red('Alternatively, pass the `--github-token` command line flag.'));
+    console.error(chalk.yellow(`You can generate a token here: ${GITHUB_TOKEN_GENERATE_URL}`));
+    process.exit(1);
+  }
+
+  await mergePullRequest(args.prNumber, githubToken);
+}