fix(karma): set defaults for karma.conf.js

The karma plugin is currently overwriting configuration set in karma.conf.js instead of merging existing values. This fix will set defaults but not overwrite existing configuration.

Author: JSMike

plugins/karma.js

@@ -9,8 +9,7 @@ const init = (config) => {
   const appConfig = angularCliConfig.apps[0];
 
   // add webpack config
-  config.webpack = getWebpackTestConfig(config.basePath, appConfig);
-  config.webpackMiddleware = {
+  const webpackMiddlewareConfig = {
     noInfo: true, // Hide webpack output because its noisy.
     stats: { // Also prevent chunk and module display output, cleaner look. Only emit errors.
       assets: false,
@@ -22,6 +21,8 @@ const init = (config) => {
       chunkModules: false
     }
   };
+  config.webpack = Object.assign(getWebpackTestConfig(config.basePath, appConfig), config.webpack);
+  config.webpackMiddleware = Object.assign(webpackMiddlewareConfig, config.webpackMiddleware);
 
   // replace the angular-cli preprocessor with webpack+sourcemap
   Object.keys(config.preprocessors)
@@ -40,4 +41,4 @@ preprocessor.$inject = []
 module.exports = Object.assign({
   'framework:angular-cli': ['factory', init],
   'preprocessor:angular-cli': ['factory', preprocessor]
-}, require('karma-webpack'), require('karma-sourcemap-loader'));
+}, require('karma-webpack'), require('karma-sourcemap-loader'));