gulp捨てられなかった

gulpfile.js

'use strict';

const autoprefixer = require('gulp-autoprefixer');
const cssnano = require('gulp-cssnano');
const gulp = require('gulp');
const gutil = require('gulp-util');
const rename = require('gulp-rename');
const sourcemaps = require('gulp-sourcemaps');
const stylus = require('gulp-stylus');
const uglify = require('gulp-uglify');
const webpack = require('webpack');
const webpackConfig = require('./webpack.config.js');

let isWatching = false;

gulp.task('bundle:js', done => {
  let isAlreadyFinished = false;

  webpack(Object.assign({}, webpackConfig, {
    watch: isWatching,
  }), (err, stats) => {
    if (err) throw new gutil.PluginError('webpack', err);

    gutil.log('\n', stats.toString({
      version: false,
      chunks: false,
      colors: true,
    }));

    if (!isAlreadyFinished) {
      done();
      isAlreadyFinished = true;
    }
  });
});

gulp.task('bundle:css', () => {
  gulp.src('./client/app.styl')
    .pipe(sourcemaps.init())
    .pipe(stylus())
    .pipe(autoprefixer())
    .pipe(cssnano())
    .pipe(rename('bundle.css'))
    .pipe(sourcemaps.write('./'))
    .pipe(gulp.dest('./public'))
});

gulp.task('bundle', ['bundle:css', 'bundle:js']);
gulp.task('watch-enable', () => isWatching = true);
gulp.task('bundle-watch', ['watch-enable', 'bundle'], () => {
  gulp.watch('./client/**/*.styl', ['bundle:css']);
});

webpack.config.js

const webpack = require('webpack');

module.exports = {
  entry: {
    'bundle.js': './client/app.js',
    'lib.js': './client/lib.js',
  },
  output: {
    path: './public',
    filename: '[name]',
  },
  externals: {
    'react': 'window.__lib__["react"]',
    'react-dom': 'window.__lib__["react-dom"]',
    'react-router': 'window.__lib__["react-router"]',
    'history': 'window.__lib__["history"]',
    'redux': 'window.__lib__["redux"]',
    'react-redux': 'window.__lib__["react-redux"]',
  },
  devtool: 'source-map',
  module: {
    loaders: [
      { test: /\.js$/, exclude: /node_modules/, loader: 'babel-loader' }
    ]
  },
  plugins: [
    new webpack.optimize.UglifyJsPlugin({ compress: { warnings: false } }),
  ],
};