feat(github-actions): introduce action to identify PRs affecting Google

.prettierignore

@@ -5,6 +5,7 @@ ng-dev/utils/protos/*.js
 
 github-actions/create-pr-for-changes/main.js
 github-actions/feature-request/main.js
+github-actions/google-internal-tests/main.js
 github-actions/lock-closed/main.js
 github-actions/commit-message-based-labels/main.js
 github-actions/slash-commands/main.js

github-actions/google-internal-tests/BUILD.bazel

@@ -0,0 +1,12 @@
+load("//tools:defaults.bzl", "esbuild_checked_in")
+
+package(default_visibility = ["//github-actions/google-internal-tests:__subpackages__"])
+
+esbuild_checked_in(
+    name = "main",
+    entry_point = "//github-actions/google-internal-tests/lib:main.ts",
+    target = "node16",
+    deps = [
+        "//github-actions/google-internal-tests/lib",
+    ],
+)

github-actions/google-internal-tests/action.yml

@@ -0,0 +1,22 @@
+name: Google Internal Tests
+description: |
+  Action for identifying pull requests which require the execution of Google Internal
+  tests. For irrelevant PRs, a status check is added to indicate the irrelevance to G3.
+author: 'Angular'
+inputs:
+  github-token:
+    required: true
+    description: GitHub Token used for creating the commit statuses.
+  affected-file-patterns:
+    required: true
+    description: |
+      List of file patterns which match files synced into Google.
+      Multiple patterns should be separated by new lines.
+  run-tests-guide-url:
+    required: false
+    description: |
+      URL to post into the GitHub commit status when Google Internal
+      tests need to be run. This is useful for helping other Googlers.
+runs:
+  using: 'node16'
+  main: 'main.js'

github-actions/google-internal-tests/lib/BUILD.bazel

@@ -0,0 +1,15 @@
+load("//tools:defaults.bzl", "ts_library")
+
+package(default_visibility = ["//github-actions/google-internal-tests:__subpackages__"])
+
+ts_library(
+    name = "lib",
+    srcs = glob(["*.ts"]),
+    deps = [
+        "@npm//@actions/core",
+        "@npm//@actions/github",
+        "@npm//@octokit/rest",
+        "@npm//@types/minimatch",
+        "@npm//minimatch",
+    ],
+)

github-actions/google-internal-tests/lib/main.ts

@@ -0,0 +1,75 @@
+import core from '@actions/core';
+import {context} from '@actions/github';
+import {Octokit} from '@octokit/rest';
+import minimatch from 'minimatch';
+
+async function main() {
+  if (context.repo.owner !== 'angular') {
+    core.info('Skipping Google Internal Tests action for non-Angular repos.');
+    return;
+  }
+  if (context.eventName !== 'pull_request_target' || context.payload.action !== 'synchronize') {
+    throw new Error(
+      'Expected Google Internal Tests action to be triggered for ' +
+        '`pull_request_target.synchronize` events.',
+    );
+  }
+
+  const githubToken = core.getInput('github-token', {required: true});
+  const rawPatterns = core.getInput('affected-file-patterns', {required: true});
+  const runTestGuideURL = core.getInput('run-tests-guide-url', {required: false});
+  const patterns = constructPatterns(rawPatterns);
+
+  const github = new Octokit({auth: githubToken});
+  const prNum = context.payload.pull_request!.number;
+  const prHeadSHA = context.payload.pull_request!.head!.sha;
+
+  const files = await github.paginate(github.pulls.listFiles, {
+    ...context.repo,
+    pull_number: prNum,
+  });
+
+  let affectsGoogle = false;
+  for (const f of files) {
+    if (patterns.some((p) => p.match(f.filename))) {
+      affectsGoogle = true;
+      break;
+    }
+  }
+
+  const waitingForG3Status = {
+    state: 'pending' as const,
+    // The initial waiting status is expected to be overridden by the
+    // internal presubmit status service then.
+    description: `Waiting for Google Internal Tests. ${
+      runTestGuideURL ? `@Googlers: See Details for instructions -->` : ''
+    }`.trim(),
+    target_url: runTestGuideURL,
+  };
+  const irrelevantToG3Status = {
+    state: 'success' as const,
+    description: 'Does not affect Google.',
+  };
+
+  await github.repos.createCommitStatus({
+    ...context.repo,
+    ...(affectsGoogle ? waitingForG3Status : irrelevantToG3Status),
+    sha: prHeadSHA,
+  });
+}
+
+function constructPatterns(rawPatterns: string): minimatch.IMinimatch[] {
+  const patterns: minimatch.IMinimatch[] = [];
+  for (let p of rawPatterns.split(/\r?\n/g)) {
+    p = p.trim();
+    if (p !== '') {
+      patterns.push(new minimatch.Minimatch(p));
+    }
+  }
+  return patterns;
+}
+
+main().catch((e: Error) => {
+  core.error(e);
+  core.setFailed(e.message);
+});