perf(aio): improve unit test rebuild time

aio/package.json

@@ -10,7 +10,7 @@
     "start": "yarn check-env && ng serve",
     "build": "yarn check-env && yarn setup && ng build -prod -sm",
     "lint": "yarn check-env && yarn docs-lint && ng lint",
-    "test": "yarn check-env && ng test --sourcemap=false",
+    "test": "yarn check-env && ng test",
     "pree2e": "yarn ~~update-webdriver",
     "e2e": "yarn check-env && ng e2e --no-webdriver-update",
     "setup": "yarn && yarn boilerplate:add && yarn docs &&  yarn generate-plunkers && yarn generate-zips",

aio/src/test-specs.ts

@@ -0,0 +1,4 @@
+// Find all the tests.
+const context = (<any>require).context('./', true, /\.spec\.ts$/);
+// And load the modules.
+context.keys().map(context);

aio/src/test.ts

@@ -1,5 +1,6 @@
 // This file is required by karma.conf.js and loads recursively all the .spec and framework files
 
+// Test dependencies.
 import 'zone.js/dist/long-stack-trace-zone';
 import 'zone.js/dist/proxy.js';
 import 'zone.js/dist/sync-test';
@@ -12,9 +13,25 @@ import {
   platformBrowserDynamicTesting
 } from '@angular/platform-browser-dynamic/testing';
 
+// List vendors here to increase test rebuild performance.
+import '@angular/common';
+import '@angular/common/testing';
+import '@angular/core/';
+import '@angular/core/testing';
+import '@angular/platform-browser';
+import '@angular/platform-browser/testing';
+import '@angular/platform-browser/animations';
+import '@angular/platform-browser-dynamic';
+import '@angular/platform-browser-dynamic/testing';
+import '@angular/http';
+import '@angular/http/testing';
+import '@angular/animations';
+import '@angular/material';
+import '@angular/service-worker';
+import 'rxjs'; // tslint:disable-line
+
 // Unfortunately there's no typing for the `__karma__` variable. Just declare it as any.
 declare var __karma__: any;
-declare var require: any;
 
 // Prevent Karma from running prematurely.
 __karma__.loaded = function () {};
@@ -24,9 +41,9 @@ getTestBed().initTestEnvironment(
   BrowserDynamicTestingModule,
   platformBrowserDynamicTesting()
 );
+
+declare var System: any;
 // Then we find all the tests.
-const context = require.context('./', true, /\.spec\.ts$/);
+System.import('./test-specs.ts')
-// And load the modules.
+  // Finally, start Karma to run the tests.
-context.keys().map(context);
+  .then(() => __karma__.start());
-// Finally, start Karma to run the tests.
-__karma__.start();

aio/src/tsconfig.app.json

@@ -9,6 +9,7 @@
   "exclude": [
     "testing/**/*",
     "test.ts",
+    "test-specs.ts",
     "**/*.spec.ts"
   ]
 }