@@ -66,6 +66,7 @@
     "isbinaryfile": "^3.0.0",
     "istanbul-instrumenter-loader": "^2.0.0",
     "json-loader": "^0.5.4",
+    "karma-source-map-support": "^1.2.0",
     "less": "^2.7.2",
     "less-loader": "^4.0.5",
     "license-webpack-plugin": "^0.4.3",
 
@@ -53,6 +53,7 @@
     "inquirer": "^3.0.0",
     "isbinaryfile": "^3.0.0",
     "json-loader": "^0.5.4",
+    "karma-source-map-support": "^1.2.0",
     "less": "^2.7.2",
     "less-loader": "^4.0.5",
     "license-webpack-plugin": "^0.4.2",
 
@@ -54,6 +54,20 @@ const init: any = (config: any, emitter: any, customFileHandlers: any) => {
     progress: true,
   }, config.angularCli);
 
+  if (testConfig.sourcemaps) {
+    config.reporters.unshift('@angular/cli');
+    // Code taken from https://github.com/tschaub/karma-source-map-support.
+    // We can't use it directly because we need to add it conditionally in this file, and karma
+    // frameworks cannot be added dynamically.
+    const smsPath = path.dirname(require.resolve('source-map-support'));
+    const ksmsPath = path.dirname(require.resolve('karma-source-map-support'));
+
+    addKarmaFiles(config.files, [
+      { pattern: path.join(smsPath, 'browser-source-map-support.js'), watched: false },
+      { pattern: path.join(ksmsPath, 'client.js'), watched: false }
+    ], true);
+  }
+
   // Add assets. This logic is mimics the one present in GlobCopyWebpackPlugin.
   if (appConfig.assets) {
     config.proxies = config.proxies || {};
@@ -227,9 +241,25 @@ function requestBlocker() {
   };
 }
 
-// Also export karma-webpack and karma-sourcemap-loader.
+// Strip the server address and webpack scheme (webpack://) from error log.
+const initSourcemapReporter: any = function (baseReporterDecorator: any) {
+  baseReporterDecorator(this);
+  const urlRegexp = /\(http:\/\/localhost:\d+\/_karma_webpack_\/webpack:\//gi;
+
+  this.onSpecComplete = function (_browser: any, result: any) {
+    if (!result.success && result.log.length > 0) {
+      result.log.forEach((log: string, idx: number) => {
+        result.log[idx] = log.replace(urlRegexp, '');
+      });
+    }
+  };
+};
+
+initSourcemapReporter.$inject = ['baseReporterDecorator'];
+
 module.exports = Object.assign({
   'framework:@angular/cli': ['factory', init],
   'preprocessor:@angular/cli': ['factory', preprocessor],
+  'reporter:@angular/cli': ['type', initSourcemapReporter],
   'middleware:angularCliBlocker': ['factory', requestBlocker]
 });