build: depend on bazelisk rather than directly on Bazel

.bazelversion

@@ -0,0 +1,3 @@
+2.1.1
+# [NB: this comment has to be after the first line, see https://github.com/bazelbuild/bazelisk/issues/117]
+# When updating the Bazel version you also need to update the RBE toolchains version in package.bzl

.circleci/config.yml

@@ -195,10 +195,11 @@ commands:
             - *cache_key_win_fallback
       # Reinstall to get windows binaries.
       - run: yarn install --frozen-lockfile --non-interactive
-      # Install @bazel/bazel globally and use that for the first run.
+      # Install @bazel/bazelisk globally and use that for the first run.
       # Workaround for https://github.com/bazelbuild/rules_nodejs/issues/894
-      - run: yarn global add @bazel/bazel@$env:BAZEL_VERSION
-      - run: bazel info
+      # NB: the issue was for @bazel/bazel but the same problem applies to @bazel/bazelisk
+      - run: yarn global add @bazel/bazelisk@$env:BAZELISK_VERSION
+      - run: bazelisk info
 
   notify_webhook_on_fail:
     description: Notify a webhook about failure

.circleci/windows-env.ps1

@@ -14,12 +14,12 @@ Add-Content $profile '$Env:path = "${Env:ProgramFiles}\nodejs\;C:\Users\circleci
 # Environment variables for Bazel
 Add-Content $profile '$Env:BAZEL_SH = "C:\tools\msys64\usr\bin\bash.exe"'
 
-# Get the bazel version devdep and store it in a global var for use in the circleci job.
-$bazelVersion = & ${Env:ProgramFiles}\nodejs\node.exe -e "console.log(require('./package.json').devDependencies['@bazel/bazel'])"
-# This is a tricky situation: we want $bazelVersion to be evaluated but not $Env:BAZEL_VERSION.
+# Get the bazelisk version devdep and store it in a global var for use in the circleci job.
+$bazeliskVersion = & ${Env:ProgramFiles}\nodejs\node.exe -e "console.log(require('./package.json').devDependencies['@bazel/bazelisk'])"
+# This is a tricky situation: we want $bazeliskVersion to be evaluated but not $Env:BAZELISK_VERSION.
 # Formatting works https://stackoverflow.com/questions/32127583/expand-variable-inside-single-quotes
-$bazelVersionGlobalVar = '$Env:BAZEL_VERSION = "{0}"' -f $bazelVersion
-Add-Content $profile $bazelVersionGlobalVar
+$bazeliskVersionGlobalVar = '$Env:BAZELISK_VERSION = "{0}"' -f $bazeliskVersion
+Add-Content $profile $bazeliskVersionGlobalVar
 
 # Remove the CircleCI checkout SSH override, because it breaks cloning repositories through Bazel.
 # See https://circleci.com/gh/angular/angular/401454 for an example.

WORKSPACE

@@ -12,23 +12,10 @@ http_archive(
     urls = ["https://github.com/bazelbuild/rules_nodejs/releases/download/1.4.1/rules_nodejs-1.4.1.tar.gz"],
 )
 
-# Check the bazel version and download npm dependencies
-load("@build_bazel_rules_nodejs//:index.bzl", "check_bazel_version", "check_rules_nodejs_version", "node_repositories", "yarn_install")
-
-# Bazel version must be at least the following version because:
-#   - 0.26.0 managed_directories feature added which is required for nodejs rules 0.30.0
-#   - 0.27.0 has a fix for managed_directories after `rm -rf node_modules`
-#   - 2.1.0 feature added to honor .bazelignore in external repositories
-check_bazel_version(
-    message = """
-You no longer need to install Bazel on your machine.
-Angular has a dependency on the @bazel/bazel package which supplies it.
-Try running `yarn bazel` instead.
-    (If you did run that, check that you've got a fresh `yarn install`)
-
-""",
-    minimum_bazel_version = "2.1.0",
-)
+# Check the rules_nodejs version and download npm dependencies
+# Note: bazel (version 2 and after) will check the .bazelversion file so we don't need to
+# assert on that.
+load("@build_bazel_rules_nodejs//:index.bzl", "check_rules_nodejs_version", "node_repositories", "yarn_install")
 
 check_rules_nodejs_version(minimum_version_string = "1.4.1")
 

aio/content/guide/bazel.md

@@ -82,16 +82,16 @@ Documentation for using Bazel for frontend projects is linked from https://docs.
 ## Running Bazel directly
 
 In some cases you'll want to bypass the Angular CLI builder, and run the Bazel CLI directly.
-The Bazel CLI is in the `@bazel/bazel` npm package.
-You can install it globally to get the `bazel` command in your path, or use `$(npm bin)/bazel` in place of bazel below.
+The Bazel tool is managed by the `@bazel/bazelisk` package (similar to how Node.js can be managed by `nvm`).
+You can install it globally to get the `bazelisk` command in your path, or use `$(npm bin)/bazelisk` in place of bazelisk below.
 
 The common commands in Bazel are:
 
-* `bazel build [targets]`: Compile the default output artifacts of the given targets.
-* `bazel test [targets]`: For whichever `*_test` targets are found in the patterns, run the tests.
-* `bazel run [target]`: Compile the program represented by target, and then run it.
+* `bazelisk build [targets]`: Compile the default output artifacts of the given targets.
+* `bazelisk test [targets]`: For whichever `*_test` targets are found in the patterns, run the tests.
+* `bazelisk run [target]`: Compile the program represented by target, and then run it.
 
-To repeat the command any time the inputs change (watch mode), replace `bazel` with `ibazel` in these commands.
+To repeat the command any time the inputs change (watch mode), replace `bazelisk` with `ibazel` in these commands.
 
 The output locations are printed in the output.
 

docs/BAZEL.md

@@ -13,7 +13,7 @@ In order to ensure that everyone builds Angular in a _consistent_ way, Bazel
 will be installed through NPM and therefore it's not necessary to install Bazel
 manually.
 
-The binaries for Bazel will be provided by the [`@bazel/bazel`](https://github.com/bazelbuild/rules_nodejs/tree/master/packages)
+The binaries for Bazel will be provided by the [`@bazel/bazelisk`](https://github.com/bazelbuild/bazelisk)
 NPM package and its platform-specific dependencies.
 
 You can access Bazel with the `yarn bazel` command

integration/angular_integration_test.bzl

@@ -26,7 +26,7 @@ NPM_PACKAGE_ARCHIVES = [
     "webdriver-manager",
     "@angular/cli",
     "@angular-devkit/build-angular",
-    "@bazel/bazel",
+    "@bazel/bazelisk",
     "@types/jasmine",
     "@types/jasminewd2",
     "@types/node",

integration/bazel-schematics/package.json

@@ -8,16 +8,15 @@
     "@angular/animations": "file:../../dist/packages-dist/animations",
     "@angular/bazel": "file:../../dist/packages-dist/bazel",
     "@angular/cli": "file:../../node_modules/@angular/cli",
-    "@angular/common": "file:../../node_modules/@angular/common",
-    "@angular/compiler": "file:../../node_modules/@angular/compiler",
-    "@angular/compiler-cli": "file:../../node_modules/@angular/compiler-cli",
-    "@angular/core": "file:../../node_modules/@angular/core",
-    "@angular/forms": "file:../../node_modules/@angular/forms",
-    "@angular/language-service": "file:../../node_modules/@angular/language-service",
-    "@angular/platform-browser": "file:../../node_modules/@angular/platform-browser",
-    "@angular/platform-browser-dynamic": "file:../../node_modules/@angular/platform-browser-dynamic",
-    "@angular/router": "file:../../node_modules/@angular/router",
-    "@bazel/bazel": "file:../../node_modules/@bazel/bazel",
+    "@angular/common": "file:../../dist/packages-dist/common",
+    "@angular/compiler": "file:../../dist/packages-dist/compiler",
+    "@angular/compiler-cli": "file:../../dist/packages-dist/compiler-cli",
+    "@angular/core": "file:../../dist/packages-dist/core",
+    "@angular/forms": "file:../../dist/packages-dist/forms",
+    "@angular/language-service": "file:../../dist/packages-dist/language-service",
+    "@angular/platform-browser": "file:../../dist/packages-dist/platform-browser",
+    "@angular/platform-browser-dynamic": "file:../../dist/packages-dist/platform-browser-dynamic",
+    "@angular/router": "file:../../dist/packages-dist/router",
     "@types/node": "file:../../node_modules/@types/node",
     "patch-package": "^6.2.1",
     "protractor": "file:../../node_modules/protractor",

integration/bazel-schematics/test.sh

@@ -52,7 +52,6 @@ function patchProtractorConf() {
 
 function testBazel() {
   # Set up
-  bazel version
   ng version
   rm -rf demo
   # Create project