chore(check-node-modules): make check/reinstall node_modules work across platforms

The previous implementations (based on shell scripts) threw errors on
Windows, because it was not able to `rm -rf` 'node_modules' (due to the
255 character limit in file-paths).

This implementation works consistently across platforms and is heavily based on
'https://github.com/angular/angular/blob/3b9c08676a4c921bbfa847802e08566fb601ba7a/tools/npm/check-node-modules.js'.

Fixes angular#11143
Closes angular#11353

Author: gkalpak

.travis.yml

@@ -48,7 +48,7 @@ install:
   - npm config set loglevel http
   - npm install -g [email protected]
   # Instal npm dependecies and ensure that npm cache is not stale
-  - scripts/npm/install-dependencies.sh
+  - node scripts/npm/check-node-modules.js --reinstall
 
 before_script:
   - mkdir -p $LOGS_DIR

Gruntfile.js

@@ -305,7 +305,7 @@ module.exports = function(grunt) {
 
     shell: {
       "npm-install": {
-        command: path.normalize('scripts/npm/install-dependencies.sh')
+        command: 'node scripts/npm/check-node-modules.js'
       },
 
       "promises-aplus-tests": {

scripts/npm/check-node-modules.js

@@ -0,0 +1,175 @@
+// Implementation based on
+// https://github.com/angular/angular/blob/3b9c08676a4c921bbfa847802e08566fb601ba7a/tools/npm/check-node-modules.js
+'use strict';
+
+// Imports
+var fs = require('fs');
+var path = require('path');
+
+// Constants
+var NPM_SHRINKWRAP_FILE = 'npm-shrinkwrap.json';
+var NPM_SHRINKWRAP_CACHED_FILE = 'node_modules/npm-shrinkwrap.cached.json';
+var FS_OPTS = {encoding: 'utf-8'};
+var PROJECT_ROOT = path.join(__dirname, '../../');
+
+// Variables
+var progressIndicatorTimer = null;
+
+// Run
+_main();
+
+// Functions - Definitions
+function _main() {
+  var reinstallIfStale = process.argv.indexOf('--reinstall') !== -1;
+  checkNodeModules(reinstallIfStale);
+}
+
+function cacheNpmShrinkwrapFile() {
+  var absoluteMarkerFilePath = path.join(PROJECT_ROOT, NPM_SHRINKWRAP_FILE);
+  var absoluteCachedMarkerFilePath = path.join(PROJECT_ROOT, NPM_SHRINKWRAP_CACHED_FILE);
+
+  startProgressIndicator('    Caching marker file...');
+  copyFile(absoluteMarkerFilePath, absoluteCachedMarkerFilePath, onCopied);
+
+  // Helpers
+  function onCopied(err) {
+    stopProgressIndicator();
+    if (err) logError(err);
+  }
+}
+
+function checkNodeModules(reinstallIfStale) {
+  var nodeModulesOk = compareMarkerFiles();
+
+  if (nodeModulesOk) {
+    console.log(':-) npm dependencies are looking good!');
+  } else {
+    console.warn(':-( npm dependencies are stale or in an unknown state!');
+
+    if (reinstallIfStale) {
+      purgeModules();
+      installModules();
+    }
+  }
+
+  return nodeModulesOk;
+}
+
+function compareMarkerFiles() {
+  var absoluteMarkerFilePath = path.join(PROJECT_ROOT, NPM_SHRINKWRAP_FILE);
+  var absoluteCachedMarkerFilePath = path.join(PROJECT_ROOT, NPM_SHRINKWRAP_CACHED_FILE);
+
+  if (!fs.existsSync(absoluteCachedMarkerFilePath)) return false;
+
+  var markerContent = fs.readFileSync(absoluteMarkerFilePath, FS_OPTS);
+  var cachedMarkerContent = fs.readFileSync(absoluteCachedMarkerFilePath, FS_OPTS);
+
+  return markerContent === cachedMarkerContent;
+}
+
+// Implementation based on
+// https://stackoverflow.com/questions/11293857/fastest-way-to-copy-file-in-node-js#answer-21995878
+function copyFile(srcPath, dstPath, callback) {
+  var callbackCalled = false;
+
+  if (!fs.existsSync(srcPath)) {
+    done(new Error('Missing source file: ' + srcPath));
+    return;
+  }
+
+  var rs = fs.createReadStream(srcPath);
+  rs.on('error', done);
+
+  var ws = fs.createWriteStream(dstPath);
+  ws.on('error', done);
+  ws.on('finish', done);
+
+  rs.pipe(ws);
+
+  // Helpers
+  function done(err) {
+    if (callback && !callbackCalled) {
+      callbackCalled = true;
+      callback(err);
+    }
+  }
+}
+
+// Custom implementation of `rm -rf` that works consistently across OSes
+function deleteDirSync(path) {
+  if (fs.existsSync(path)) {
+    fs.readdirSync(path).forEach(deleteDirOrFileSync);
+    fs.rmdirSync(path);
+  }
+
+  // Helpers
+  function deleteDirOrFileSync(subpath) {
+    var curPath = path + '/' + subpath;
+
+    if (fs.lstatSync(curPath).isDirectory()) {
+      deleteDirSync(curPath);
+    } else {
+      fs.unlinkSync(curPath);
+    }
+  }
+}
+
+function installModules() {
+  startProgressIndicator('    Running `npm install` (this may take a while)...');
+
+  var exec = require('child_process').exec;
+  var opts = {cwd: PROJECT_ROOT};
+  var proc = exec('npm install', opts, onInstalled);
+
+  // TODO(gkalpak): Decide if we actually want these
+  // proc.stdout.pipe(process.stdout);
+  // proc.stderr.pipe(process.stderr);
+
+  // Helpers
+  function onInstalled(err) {
+    stopProgressIndicator();
+
+    if (err) {
+      logError(err);
+      return;
+    }
+
+    cacheNpmShrinkwrapFile();
+  }
+}
+
+function purgeModules() {
+  startProgressIndicator('    Purging \'node_modules\'...');
+
+  var nodeModulesPath = path.join(PROJECT_ROOT, 'node_modules');
+  deleteDirSync(nodeModulesPath);
+
+  stopProgressIndicator();
+}
+
+function logError(err) {
+  var separator = new Array(81).join('!');
+
+  console.error(separator);
+  console.error('Operation completed with errors:');
+  console.error(err);
+  console.error(separator);
+}
+
+function startProgressIndicator(taskDescription) {
+  stopProgressIndicator();
+
+  var stdout = process.stdout;
+
+  stdout.write(taskDescription);
+  progressIndicatorTimer = setInterval(stdout.write.bind(stdout, '.'), 5000);
+}
+
+function stopProgressIndicator() {
+  if (progressIndicatorTimer) {
+    clearInterval(progressIndicatorTimer);
+    progressIndicatorTimer = null;
+
+    process.stdout.write('\n');
+  }
+}