chore(*): use Yarn for dependency management

.nvmrc

@@ -1,2 +1 @@
-4
-
+6

.travis.yml

@@ -1,7 +1,7 @@
 language: node_js
 sudo: false
 node_js:
-  - '4.4'
+  - '6'
 
 cache:
   directories:
@@ -36,19 +36,12 @@ addons:
     packages:
       - g++-4.8
 
-install:
-  # Check the size of caches
-  - du -sh ./node_modules ./bower_components/ ./docs/bower_components/ || true
-  # - npm config set registry http://23.251.144.68
-  # Disable the spinner, it looks bad on Travis
-  - npm config set spin false
-  # Log HTTP requests
-  - npm config set loglevel http
-  #- npm install -g [email protected]
-  # Install npm dependencies and ensure that npm cache is not stale
-  - npm install
+before_install:
+  - curl -o- -L https://raw.githubusercontent.com/yarnpkg/yarn/2a0afc73210c7a82082585283e518eeb88ca19ae/scripts/install-latest.sh | bash -s -- --version 0.17.9
+  - export PATH=$HOME/.yarn/bin:$PATH
 
 before_script:
+  - du -sh ./node_modules ./bower_components/ ./docs/bower_components/ || true
   - ./scripts/travis/before_build.sh
 
 script:

CONTRIBUTING.md

@@ -209,7 +209,9 @@ We have very precise rules over how our git commit messages can be formatted.  T
 readable messages** that are easy to follow when looking through the **project history**.  But also,
 we use the git commit messages to **generate the AngularJS change log**.
 
-The commit message formatting can be added using a typical git workflow or through the use of a CLI wizard ([Commitizen](https://github.com/commitizen/cz-cli)). To use the wizard, run `npm run commit` in your terminal after staging your changes in git.
+The commit message formatting can be added using a typical git workflow or through the use of a CLI
+wizard ([Commitizen](https://github.com/commitizen/cz-cli)). To use the wizard, run `yarn run commit`
+in your terminal after staging your changes in git.
 
 ### Commit Message Format
 Each commit message consists of a **header**, a **body** and a **footer**.  The header has a special
@@ -229,7 +231,8 @@ Any line of the commit message cannot be longer 100 characters! This allows the
 to read on GitHub as well as in various git tools.
 
 ### Revert
-If the commit reverts a previous commit, it should begin with `revert: `, followed by the header of the reverted commit. In the body it should say: `This reverts commit <hash>.`, where the hash is the SHA of the commit being reverted.
+If the commit reverts a previous commit, it should begin with `revert: `, followed by the header of the reverted commit.
+In the body it should say: `This reverts commit <hash>.`, where the hash is the SHA of the commit being reverted.
 
 ### Type
 Must be one of the following:
@@ -266,7 +269,8 @@ The body should include the motivation for the change and contrast this with pre
 The footer should contain any information about **Breaking Changes** and is also the place to
 [reference GitHub issues that this commit closes][closing-issues].
 
-**Breaking Changes** should start with the word `BREAKING CHANGE:` with a space or two newlines. The rest of the commit message is then used for this.
+**Breaking Changes** should start with the word `BREAKING CHANGE:` with a space or two newlines.
+The rest of the commit message is then used for this.
 
 A detailed explanation can be found in this [document][commit-message-format].
 

Gruntfile.js

@@ -10,26 +10,63 @@ var path = require('path');
 var e2e = require('./test/e2e/tools');
 
 var semver = require('semver');
-var fs = require('fs');
+var exec = require('shelljs').exec;
+var pkg = require(__dirname + '/package.json');
 
-var useNodeVersion = fs.readFileSync('.nvmrc', 'utf8');
-if (!semver.satisfies(process.version, useNodeVersion)) {
-  throw new Error('Invalid node version; please use node v' + useNodeVersion);
+// Node.js version checks
+if (!semver.satisfies(process.version, pkg.engines.node)) {
+  reportOrFail('Invalid node version (' + process.version + '). ' +
+               'Please use a version that satisfies ' + pkg.engines.node);
 }
 
+// Yarn version checks
+var expectedYarnVersion = pkg.engines.yarn;
+var currentYarnVersion = exec('yarn --version', {silent: true}).stdout.trim();
+if (!semver.satisfies(currentYarnVersion, expectedYarnVersion)) {
+  reportOrFail('Invalid yarn version (' + currentYarnVersion + '). ' +
+               'Please use a version that satisfies ' + expectedYarnVersion);
+}
+
+// Grunt CLI version checks
+var expectedGruntVersion = pkg.engines.grunt;
+var currentGruntVersions = exec('grunt --version', {silent: true}).stdout;
+var match = /^grunt-cli v(.+)$/m.exec(currentGruntVersions);
+if (!match) {
+  reportOrFail('Unable to compute the current grunt-cli version. We found:\n' +
+               currentGruntVersions);
+} else {
+  if (!semver.satisfies(match[1], expectedGruntVersion)) {
+  reportOrFail('Invalid grunt-cli version (' + match[1] + '). ' +
+               'Please use a version that satisfies ' + expectedGruntVersion);
+  }
+}
+
+// Ensure Node.js dependencies have been installed
+if (!process.env.TRAVIS && !process.env.JENKINS_HOME) {
+  var yarnOutput = exec('yarn install');
+  if (yarnOutput.code !== 0) {
+    throw new Error('Yarn install failed: ' + yarnOutput.stderr);
+  }
+}
+
+
 module.exports = function(grunt) {
-  //grunt plugins
+
+  // this loads all the node_modules that start with `grunt-` as plugins
   require('load-grunt-tasks')(grunt);
 
+  // load additional grunt tasks
   grunt.loadTasks('lib/grunt');
   grunt.loadNpmTasks('angular-benchpress');
 
+  // compute version related info for this build
   var NG_VERSION = versionInfo.currentVersion;
   NG_VERSION.cdn = versionInfo.cdnVersion;
   var dist = 'angular-' + NG_VERSION.full;
 
   if (versionInfo.cdnVersion == null) {
-    throw new Error('Unable to read CDN version, are you offline or has the CDN not been properly pushed?');
+    throw new Error('Unable to read CDN version, are you offline or has the CDN not been properly pushed?\n' +
+                    'Perhaps you want to set the NG1_BUILD_NO_REMOTE_VERSION_REQUESTS environment variable?');
   }
 
   //config
@@ -292,10 +329,9 @@ module.exports = function(grunt) {
     },
 
     shell: {
-      'npm-install': {
-        command: 'node scripts/npm/check-node-modules.js'
+      'install-node-dependencies': {
+        command: 'yarn'
       },
-
       'promises-aplus-tests': {
         options: {
           stdout: false,
@@ -322,13 +358,6 @@ module.exports = function(grunt) {
     }
   });
 
-  // global beforeEach task
-  if (!process.env.TRAVIS) {
-    grunt.task.run('shell:npm-install');
-  }
-
-
-
   //alias tasks
   grunt.registerTask('test', 'Run unit, docs and e2e tests with Karma', ['eslint', 'package', 'test:unit', 'test:promises-aplus', 'tests:docs', 'test:protractor']);
   grunt.registerTask('test:jqlite', 'Run the unit tests with Karma' , ['tests:jqlite']);
@@ -350,3 +379,14 @@ module.exports = function(grunt) {
   grunt.registerTask('ci-checks', ['ddescribe-iit', 'merge-conflict', 'eslint']);
   grunt.registerTask('default', ['package']);
 };
+
+
+function reportOrFail(message) {
+  if (process.env.TRAVIS || process.env.JENKINS_HOME) {
+    throw new Error(message);
+  } else {
+    console.log('===============================================================================');
+    console.log(message);
+    console.log('===============================================================================');
+  }
+}

TRIAGING.md

@@ -95,7 +95,7 @@ You can mention him in the relevant thread like this: `@btford`.
 
 > Thanks for submitting this issue!
 > Unfortunately, we don't think this functionality belongs in core.
-> The good news is that you could easily implement this as a third-party module and publish it on Bower and/or npm.
+> The good news is that you could easily implement this as a third-party module and publish it on Bower and/or to the npm repository.
 
 
 ## Assigning Work