feat(dev-infra): create environment stamping script in ng-dev (#36844)

Create a common environment stamping script in the ng-dev tooling
as to be used in common release tasks.  This is the first step in
consolidating pieces of the release scripting process into a single
location to develop a release tool.

PR Close #36844

dev-infra/BUILD.bazel

@@ -11,6 +11,7 @@ ts_library(
         "//dev-infra/commit-message",
         "//dev-infra/format",
         "//dev-infra/pullapprove",
+        "//dev-infra/release",
         "//dev-infra/ts-circular-dependencies",
         "//dev-infra/utils",
         "@npm//@types/node",

dev-infra/cli.ts

@@ -11,14 +11,16 @@ import {tsCircularDependenciesBuilder} from './ts-circular-dependencies/index';
 import {buildPullapproveParser} from './pullapprove/cli';
 import {buildCommitMessageParser} from './commit-message/cli';
 import {buildFormatParser} from './format/cli';
+import {buildReleaseParser} from './release/cli';
 
 yargs.scriptName('ng-dev')
     .demandCommand()
     .recommendCommands()
-    .command('ts-circular-deps <command>', '', tsCircularDependenciesBuilder)
-    .command('pullapprove <command>', '', buildPullapproveParser)
     .command('commit-message <command>', '', buildCommitMessageParser)
     .command('format <command>', '', buildFormatParser)
+    .command('pullapprove <command>', '', buildPullapproveParser)
+    .command('release <command>', '', buildReleaseParser)
+    .command('ts-circular-deps <command>', '', tsCircularDependenciesBuilder)
     .wrap(120)
     .strict()
     .parse();

dev-infra/release/BUILD.bazel

@@ -0,0 +1,17 @@
+load("@npm_bazel_typescript//:index.bzl", "ts_library")
+
+ts_library(
+    name = "release",
+    srcs = glob([
+        "*.ts",
+    ]),
+    module_name = "@angular/dev-infra-private/release",
+    visibility = ["//dev-infra:__subpackages__"],
+    deps = [
+        "@npm//@types/node",
+        "@npm//@types/shelljs",
+        "@npm//@types/yargs",
+        "@npm//shelljs",
+        "@npm//yargs",
+    ],
+)

dev-infra/release/cli.ts

@@ -0,0 +1,19 @@
+/**
+ * @license
+ * Copyright Google Inc. 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 * as yargs from 'yargs';
+import {buildEnvStamp} from './env-stamp';
+
+/** Build the parser for the release commands. */
+export function buildReleaseParser(localYargs: yargs.Argv) {
+  return localYargs.help().strict().demandCommand().command(
+      'build-env-stamp', 'Build the environment stamping information', {}, () => buildEnvStamp());
+}
+
+if (require.main === module) {
+  buildReleaseParser(yargs).parse();
+}

dev-infra/release/env-stamp.ts

@@ -0,0 +1,64 @@
+/**
+ * @license
+ * Copyright Google Inc. 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 {exec as _exec} from 'shelljs';
+
+/**
+ * Log the environment variables expected by bazel for stamping.
+ *
+ * See the section on stamping in docs / BAZEL.md
+ *
+ * This script must be a NodeJS script in order to be cross-platform.
+ * See https://github.com/bazelbuild/bazel/issues/5958
+ * Note: git operations, especially git status, take a long time inside mounted docker volumes
+ * in Windows or OSX hosts (https://github.com/docker/for-win/issues/188).
+ */
+export function buildEnvStamp() {
+  console.info(`BUILD_SCM_BRANCH ${getCurrentBranch()}`);
+  console.info(`BUILD_SCM_COMMIT_SHA ${getCurrentSha()}`);
+  console.info(`BUILD_SCM_HASH ${getCurrentSha()}`);
+  console.info(`BUILD_SCM_LOCAL_CHANGES ${hasLocalChanges()}`);
+  console.info(`BUILD_SCM_USER ${getCurrentGitUser()}`);
+  console.info(`BUILD_SCM_VERSION ${getSCMVersion()}`);
+  process.exit(0);
+}
+
+/** Run the exec command and return the stdout as a trimmed string. */
+function exec(cmd: string) {
+  return _exec(cmd, {silent: true}).toString().trim();
+}
+
+/** Whether the repo has local changes. */
+function hasLocalChanges() {
+  return !!exec(`git status --untracked-files=no --porcelain`);
+}
+
+/** Get the version based on the most recent semver tag. */
+function getSCMVersion() {
+  const version = exec(`git describe --match [0-9]*.[0-9]*.[0-9]* --abbrev=7 --tags HEAD`);
+  return `${version.replace(/-([0-9]+)-g/, '+$1.sha-')}${
+      (hasLocalChanges() ? '.with-local-changes' : '')}`;
+}
+
+/** Get the current SHA of HEAD. */
+function getCurrentSha() {
+  return exec(`git rev-parse HEAD`);
+}
+
+/** Get the currently checked out branch. */
+function getCurrentBranch() {
+  return exec(`git symbolic-ref --short HEAD`);
+}
+
+/** Get the current git user based on the git config. */
+function getCurrentGitUser() {
+  const userName = exec(`git config user.name`);
+  const userEmail = exec(`git config user.email`);
+
+  return `${userName} <${userEmail}>`;
+}