diff --git a/packages/@angular/cli/models/webpack-config.ts b/packages/@angular/cli/models/webpack-config.ts
index c6a78c74ddda..3e331571abb7 100644
--- a/packages/@angular/cli/models/webpack-config.ts
+++ b/packages/@angular/cli/models/webpack-config.ts
@@ -14,16 +14,16 @@ import {
 import * as path from 'path';
 import { AngularCompilerPlugin } from '@ngtools/webpack';
 
-export interface WebpackConfigOptions {
+export interface WebpackConfigOptions<T extends BuildOptions = BuildOptions> {
   projectRoot: string;
-  buildOptions: BuildOptions;
+  buildOptions: T;
   appConfig: any;
 }
 
-export class NgCliWebpackConfig {
+export class NgCliWebpackConfig<T extends BuildOptions = BuildOptions> {
   public config: any;
-  public wco: WebpackConfigOptions;
-  constructor(buildOptions: BuildOptions, appConfig: any) {
+  public wco: WebpackConfigOptions<T>;
+  constructor(buildOptions: T, appConfig: any) {
 
     this.validateBuildOptions(buildOptions);
 
@@ -59,7 +59,7 @@ export class NgCliWebpackConfig {
     return this.config;
   }
 
-  public getTargetConfig(webpackConfigOptions: WebpackConfigOptions): any {
+  public getTargetConfig(webpackConfigOptions: WebpackConfigOptions<T>): any {
     switch (webpackConfigOptions.buildOptions.target) {
       case 'development':
         return getDevConfig(webpackConfigOptions);
@@ -86,8 +86,8 @@ export class NgCliWebpackConfig {
   }
 
   // Fill in defaults for build targets
-  public addTargetDefaults(buildOptions: BuildOptions): BuildOptions {
-    const targetDefaults: { [target: string]: BuildOptions } = {
+  public addTargetDefaults(buildOptions: T): T {
+    const targetDefaults: { [target: string]: Partial<BuildOptions> } = {
       development: {
         environment: 'dev',
         outputHashing: 'media',
@@ -110,8 +110,8 @@ export class NgCliWebpackConfig {
   }
 
   // Fill in defaults from .angular-cli.json
-  public mergeConfigs(buildOptions: BuildOptions, appConfig: any, projectRoot: string) {
-    const mergeableOptions = {
+  public mergeConfigs(buildOptions: T, appConfig: any, projectRoot: string): T {
+    const mergeableOptions: Partial<BuildOptions> = {
       outputPath: path.resolve(projectRoot, appConfig.outDir),
       deployUrl: appConfig.deployUrl,
       baseHref: appConfig.baseHref
diff --git a/packages/@angular/cli/models/webpack-configs/development.ts b/packages/@angular/cli/models/webpack-configs/development.ts
index dc1eb85a882e..5b2227cc51a6 100644
--- a/packages/@angular/cli/models/webpack-configs/development.ts
+++ b/packages/@angular/cli/models/webpack-configs/development.ts
@@ -2,8 +2,8 @@ import { NamedModulesPlugin } from 'webpack';
 
 import { WebpackConfigOptions } from '../webpack-config';
 
-export const getDevConfig = function (_wco: WebpackConfigOptions) {
+export function getDevConfig(_wco: WebpackConfigOptions) {
   return {
     plugins: [new NamedModulesPlugin()]
   };
-};
+}
diff --git a/packages/@angular/cli/models/webpack-configs/production.ts b/packages/@angular/cli/models/webpack-configs/production.ts
index 23ccfc360e24..c7e5917b331c 100644
--- a/packages/@angular/cli/models/webpack-configs/production.ts
+++ b/packages/@angular/cli/models/webpack-configs/production.ts
@@ -14,7 +14,7 @@ import { readTsconfig } from '../../utilities/read-tsconfig';
 const UglifyJSPlugin = require('uglifyjs-webpack-plugin');
 
 
-export const getProdConfig = function (wco: WebpackConfigOptions) {
+export function getProdConfig(wco: WebpackConfigOptions) {
   const { projectRoot, buildOptions, appConfig } = wco;
 
   let extraPlugins: any[] = [];
@@ -159,4 +159,4 @@ export const getProdConfig = function (wco: WebpackConfigOptions) {
       ...extraPlugins
     ]
   };
-};
+}
diff --git a/packages/@angular/cli/models/webpack-configs/server.ts b/packages/@angular/cli/models/webpack-configs/server.ts
index 262849877de2..c3e5fb465587 100644
--- a/packages/@angular/cli/models/webpack-configs/server.ts
+++ b/packages/@angular/cli/models/webpack-configs/server.ts
@@ -4,7 +4,7 @@ import { WebpackConfigOptions } from '../webpack-config';
  * Returns a partial specific to creating a bundle for node
  * @param _wco Options which are include the build options and app config
  */
-export const getServerConfig = function (_wco: WebpackConfigOptions) {
+export function getServerConfig(_wco: WebpackConfigOptions) {
   return {
     target: 'node',
     output: {
@@ -35,4 +35,4 @@ export const getServerConfig = function (_wco: WebpackConfigOptions) {
       }
     ]
   };
-};
+}
diff --git a/packages/@angular/cli/models/webpack-configs/test.ts b/packages/@angular/cli/models/webpack-configs/test.ts
index 6405b8b8afad..73c54824bb11 100644
--- a/packages/@angular/cli/models/webpack-configs/test.ts
+++ b/packages/@angular/cli/models/webpack-configs/test.ts
@@ -4,6 +4,7 @@ import * as webpack from 'webpack';
 
 import { CliConfig } from '../config';
 import { WebpackTestOptions } from '../webpack-test-config';
+import { WebpackConfigOptions } from '../webpack-config';
 
 
 /**
@@ -15,16 +16,14 @@ import { WebpackTestOptions } from '../webpack-test-config';
  */
 
 
-export function getTestConfig(testConfig: WebpackTestOptions) {
+export function getTestConfig(wco: WebpackConfigOptions<WebpackTestOptions>) {
+  const { projectRoot, buildOptions, appConfig } = wco;
 
-  const configPath = CliConfig.configFilePath();
-  const projectRoot = path.dirname(configPath);
-  const appConfig = CliConfig.fromProject().config.apps[0];
   const nodeModules = path.resolve(projectRoot, 'node_modules');
   const extraRules: any[] = [];
   const extraPlugins: any[] = [];
 
-  if (testConfig.codeCoverage && CliConfig.fromProject()) {
+  if (buildOptions.codeCoverage && CliConfig.fromProject()) {
     const codeCoverageExclude = CliConfig.fromProject().get('test.codeCoverage.exclude');
     let exclude: (string | RegExp)[] = [
       /\.(e2e|spec)\.ts$/,
@@ -49,7 +48,7 @@ export function getTestConfig(testConfig: WebpackTestOptions) {
   }
 
   return {
-    devtool: testConfig.sourcemaps ? 'inline-source-map' : 'eval',
+    devtool: buildOptions.sourcemaps ? 'inline-source-map' : 'eval',
     entry: {
       main: path.resolve(projectRoot, appConfig.root, appConfig.test)
     },
diff --git a/packages/@angular/cli/models/webpack-configs/typescript.ts b/packages/@angular/cli/models/webpack-configs/typescript.ts
index 472df1139f11..c1c4ccee50cc 100644
--- a/packages/@angular/cli/models/webpack-configs/typescript.ts
+++ b/packages/@angular/cli/models/webpack-configs/typescript.ts
@@ -83,7 +83,7 @@ function _createAotPlugin(wco: WebpackConfigOptions, options: any) {
   }
 }
 
-export const getNonAotConfig = function(wco: WebpackConfigOptions) {
+export function getNonAotConfig(wco: WebpackConfigOptions) {
   const { appConfig, projectRoot } = wco;
   const tsConfigPath = path.resolve(projectRoot, appConfig.root, appConfig.tsconfig);
 
@@ -91,9 +91,9 @@ export const getNonAotConfig = function(wco: WebpackConfigOptions) {
     module: { rules: [{ test: /\.ts$/, loader: webpackLoader }] },
     plugins: [ _createAotPlugin(wco, { tsConfigPath, skipCodeGeneration: true }) ]
   };
-};
+}
 
-export const getAotConfig = function(wco: WebpackConfigOptions) {
+export function getAotConfig(wco: WebpackConfigOptions) {
   const { projectRoot, buildOptions, appConfig } = wco;
   const tsConfigPath = path.resolve(projectRoot, appConfig.root, appConfig.tsconfig);
   const testTsConfigPath = path.resolve(projectRoot, appConfig.root, appConfig.testTsconfig);
@@ -119,9 +119,9 @@ export const getAotConfig = function(wco: WebpackConfigOptions) {
     module: { rules: [{ test: /\.ts$/, use: [...boLoader, webpackLoader] }] },
     plugins: [ _createAotPlugin(wco, pluginOptions) ]
   };
-};
+}
 
-export const getNonAotTestConfig = function(wco: WebpackConfigOptions) {
+export function getNonAotTestConfig(wco: WebpackConfigOptions) {
   const { projectRoot, appConfig } = wco;
   const tsConfigPath = path.resolve(projectRoot, appConfig.root, appConfig.testTsconfig);
   const appTsConfigPath = path.resolve(projectRoot, appConfig.root, appConfig.tsconfig);
@@ -137,4 +137,4 @@ export const getNonAotTestConfig = function(wco: WebpackConfigOptions) {
     module: { rules: [{ test: /\.ts$/, loader: webpackLoader }] },
     plugins: [ _createAotPlugin(wco, pluginOptions) ]
   };
-};
+}
diff --git a/packages/@angular/cli/models/webpack-test-config.ts b/packages/@angular/cli/models/webpack-test-config.ts
index b9de83223662..4847293867e1 100644
--- a/packages/@angular/cli/models/webpack-test-config.ts
+++ b/packages/@angular/cli/models/webpack-test-config.ts
@@ -12,18 +12,18 @@ import {
 export interface WebpackTestOptions extends BuildOptions {
   codeCoverage?: boolean;
 }
-export class WebpackTestConfig extends NgCliWebpackConfig {
-  constructor(private testOptions: WebpackTestOptions, appConfig: any) {
+export class WebpackTestConfig extends NgCliWebpackConfig<WebpackTestOptions> {
+  constructor(testOptions: WebpackTestOptions, appConfig: any) {
     super(testOptions, appConfig);
   }
 
   public buildConfig() {
-    let webpackConfigs = [
+    const webpackConfigs = [
       getCommonConfig(this.wco),
       getStylesConfig(this.wco),
       this.getTargetConfig(this.wco),
       getNonAotTestConfig(this.wco),
-      getTestConfig(this.testOptions)
+      getTestConfig(this.wco)
     ];
 
     this.config = webpackMerge(webpackConfigs);