context replacement plugin

    new webpack.ContextReplacementPlugin(/\@angular(\\|\/)core(\\|\/)esm5/, path.join(__dirname, './client')),

helpers.js

var path = require('path');
var _root = path.resolve(__dirname, '..');
function root(args) {
    args = Array.prototype.slice.call(arguments, 0);
    return path.join.apply(path, [_root].concat(args));
}
exports.root = root;

karma-test-shim.js

Error.stackTraceLimit = Infinity;

require('core-js/es6');
require('core-js/es7/reflect');

require('zone.js/dist/zone');
require('zone.js/dist/long-stack-trace-zone');
require('zone.js/dist/proxy');
require('zone.js/dist/sync-test');
require('zone.js/dist/jasmine-patch');
require('zone.js/dist/async-test');
require('zone.js/dist/fake-async-test');

var appContext = require.context('../public/app', true, /\.spec\.ts/);

appContext.keys().forEach(appContext);

var testing = require('@angular/core/testing');
var browser = require('@angular/platform-browser-dynamic/testing');

testing.TestBed.initTestEnvironment(browser.BrowserDynamicTestingModule, browser.platformBrowserDynamicTesting());

webpack.dev.js

const path = require('path');
const webpack = require('webpack');
const helpers = require('./helpers');

const HtmlWebpackPlugin = require('html-webpack-plugin');
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;

const ENV = process.env.NODE_ENV = process.env.ENV = 'development';

module.exports = {

  entry: {
    'polyfills': './public/polyfills.ts',
    'vendor': './public/vendor.ts',
    'ng1': './public/index.ts',
    'app': './public/main.ts'
  },

  output: {
    path: helpers.root('dist/dev'),
    publicPath: '/',
    filename: '[name].bundle.js',
    chunkFilename: '[id].chunk.js'
  },

  resolve: {
    extensions: ['.ts', '.js']
  },

  module: {
    rules: [
      {
        test: /\.ts$/,
        loaders: ['awesome-typescript-loader', 'angular2-template-loader']
      },
      {
        test: /\.html$/,
        loader: 'html-loader'
      }
    ]
  },

  plugins: [
    new webpack.optimize.CommonsChunkPlugin({
      name: 'common',
      minChunks: Infinity
    }),

    new webpack.optimize.CommonsChunkPlugin({
      name: 'vendor',
      chunks: ['vendor', 'app'],
      minChunks: 2
    }),


    new webpack.SourceMapDevToolPlugin({
      'filename': '[file].map[query]',
      'moduleFilenameTemplate': '[resource-path]',
      'fallbackModuleFilenameTemplate': '[resource-path]?[hash]',
      'sourceRoot': 'webpack:///'
    }),

    new HtmlWebpackPlugin({
      template: 'config/index.html',
      chunks: ['app']
    }),

    new webpack.DefinePlugin({
      'process.env': {
        'ENV': JSON.stringify(ENV)
      }
    }),

    new webpack.ContextReplacementPlugin(/\@angular(\\|\/)core(\\|\/)esm5/, path.join(__dirname, './client')),

    // new BundleAnalyzerPlugin({
    //   analyzerMode: 'static'
    // })
  ]
}

webpack.test.js

const webpack = require('webpack');
const helpers = require('./helpers');

module.exports = {

  devtool: 'inline-source-map',

  resolve: {
    extensions: ['.ts', '.js']
  },

  module: {
    rules: [
      {
        test: /\.ts$/,
        loaders: ['awesome-typescript-loader', 'angular2-template-loader']
      },
      {
        test: /\.html$/,
        loader: 'html-loader'
      }
    ]
  },

  plugins: [
    new webpack.ContextReplacementPlugin(/\@angular(\\|\/)core(\\|\/)esm5/, path.join(__dirname, './client')),


  ]
}