How to use the webpack.ProvidePlugin function in webpack

dir : 'coverage/'
		},

		webpackMiddleware: {
			// webpack-dev-middleware configuration
			// i. e.
			noInfo: true
		},

		webpack: {
			resolve: {
				// Everything relative to repo root
				root: path.resolve(path.join(__dirname, '..', '..'))
			},
			plugins: [
				new webpack.ProvidePlugin(require('./karmaWebpackProvidePluginSettings'))
			]
		}
	});
};

module.exports = (skpmConfig, getTestFiles, argv, logProgress) => config => {
  config.output.filename = 'compiled-tests.js'
  config.output.path = path.resolve(
    __dirname,
    '../../test-runner.sketchplugin/Contents/Sketch'
  )
  // https://webpack.js.org/configuration/output/#output-devtoolmodulefilenametemplate
  config.output.devtoolModuleFilenameTemplate = '[absolute-resource-path]'

  config.plugins.push(
    new webpack.ProvidePlugin({
      expect: require.resolve('../../expect'),
    })
  )

  if (!argv.buildOnly) {
    config.plugins.push(
      // eslint-disable-next-line
      new WebpackTestRunner({
        script: sketchtoolRunCommand(
          path.resolve(__dirname, '../../test-runner.sketchplugin'),
          'plugin-tests',
          {
            app: argv.app,
            withoutActivating: true,
            handleError: false,
          }

// External libs
var webpack = require('webpack');
var path = require('path');

// Put React as a global variable
var providePlugin = new webpack.ProvidePlugin({
  'React': 'react',
  'Immutable': 'immutable',
  $: 'jquery',
  'window.$': 'jquery',
  'window.jQuery': 'jquery',
  'jQuery': 'jquery',
  '_': 'underscore',
  UI: '!json-loader!' + path.resolve(__dirname, './client/style/ui-kit.json'),
  'es6-promise': 'es6-promise',
  fetch: 'imports?this=>global!exports?global.fetch!whatwg-fetch',
});

var definePlugin = new webpack.DefinePlugin({
  'process.env.FIREBASE_API_KEY': JSON.stringify(process.env.FIREBASE_API_KEY),
  'process.env.FIREBASE_AUTH_DOMAIN': JSON.stringify(process.env.FIREBASE_AUTH_DOMAIN),
  'process.env.FIREBASE_DATABASE_URL': JSON.stringify(process.env.FIREBASE_DATABASE_URL),

//输出位置为./assests
    output: {
        path: path.join(process.cwd(), 'assets'),
        filename: jsDir + '[name].js',
        publicPath: '/'
    },
    plugins: [
        //排除css压缩加载在页面
        new ExtractTextPlugin(cssDir + '[name].css'),
        //合并额外的js包(暂时无用)
        // new CommonsChunkPlugin('lib', './dist/js/lib.js', jsExtract),
        //开启热加载模式
        new webpack.HotModuleReplacementPlugin(),
        new webpack.NoErrorsPlugin(),
        //设置全局使用的变量
        new webpack.ProvidePlugin(globalValue),
        new webpack.optimize.UglifyJsPlugin({
            compressor: {
                warnings: false
            }
        })
    ],
    module: {
        //加载器配置
        loaders: [
            //css加载器 排除不需要加css-modules的css部分
            {
                test: /\.css$/,
                exclude: getExcludeCss(),
                loaders: [
                    'style-loader',
                    'css-loader?modules&localIdentName=[name]__[local]___[hash:base64:5]&sourceMap&importLoaders=1',

config.module.loaders.push(cssLoader);

    config.postcss = [
        autoprefixer({
            browsers: ['last 2 version']
        })
    ];

    config.plugins = [
        new ExtractTextPlugin('[name].[hash].css', {
            disable: !BUILD || TEST
        }),

        // Provide jquery
        new webpack.ProvidePlugin({
            $: 'jquery',
            jQuery: 'jquery',
            'window.jQuery': 'jquery'
        })
    ];

    if (!TEST) {
        config.plugins.push(
            new HtmlWebpackPlugin({
                template: './public/index.html',
                inject: 'body'
            })
        )
    }

    if (BUILD) {

function getImplicitGlobals() {
  return new webpack.ProvidePlugin({
    $:      'jquery',
    jQuery: 'jquery',
    jquery: 'jquery'
  });
}

function provide(app, helpers) {
  if (!app.provide) return app
  var webpack = require('webpack')

  return helpers.injectPlugins(app, new webpack.ProvidePlugin(app.provide))
}

/*
 |--------------------------------------------------------------------------
 | Plugins
 |--------------------------------------------------------------------------
 |
 | Lastly, we'll register a number of plugins to extend and configure
 | Webpack. To get you started, we've included a handful of useful
 | extensions, for versioning, OS notifications, and much more.
 |
 */

plugins.push(
    new webpack.ProvidePlugin(Mix.autoload || {}),

    new webpackPlugins.FriendlyErrorsWebpackPlugin({ clearConsole: Mix.options.clearConsole }),

    new webpackPlugins.StatsWriterPlugin({
        filename: 'mix-manifest.json',
        transform: Mix.manifest.transform.bind(Mix.manifest),
    }),

    new webpack.LoaderOptionsPlugin({
        minimize: Mix.inProduction,
        options: {
            postcss: Mix.options.postCss,
            context: __dirname,
            output: { path: './' }
        }
    })

function productionPlugins()
{
    return [
        new webpack.DefinePlugin({
            'process.env': {
                NODE_ENV: JSON.stringify('production')
            }
        }),
        new webpack.ProvidePlugin({
            URLSearchParams: "url-search-params"
        }),
        new webpack.optimize.UglifyJsPlugin(),
        new webpack.optimize.OccurrenceOrderPlugin(true),
    ]
}

function plugins(config, isDev) {

    var internalKeyDefinitions = Object
        .keys(internalKeys)
        .reduce((keys, key) => {
            keys[key] = `"${internalKeys[key]}"`;
            return keys;
        }, {});

    var plugins = [
        new webpack.NoErrorsPlugin(),
        new webpack.DefinePlugin({ DEBUG: isDev }),
        new webpack.DefinePlugin(internalKeyDefinitions),
        new webpack.ProvidePlugin({ 'Promise': 'es6-promise' }),
        new webpack.optimize.DedupePlugin(),
        new webpack.optimize.AggressiveMergingPlugin(),
        new webpack.optimize.OccurrenceOrderPlugin(true),
        new webpack.LoaderOptionsPlugin({
            debug: isDev,
            queit: true,
            silent: true,
            minimize: false,
            progress: false,
        }),
    ];
    if (isDev) {
        plugins.push(new WebpackVisualizer());
    } else {
        plugins.push(new ClosureCompilerPlugin({
            compiler: {