Improves eslint rules (#785)

* Switch to airbnb's eslint

* Applies automatic fixes

* Clean up dependencies

* New lint rules

* Apply auto fixes

* Prettier

* Update prettier position in eslint config

* Aligns prettier and eslint

* Use partial configs for client and server directories

* Finalizes eslint config (for now)

* Applies all elsint fixes

* Removes duplciated config

* Fixes build & local dev

* Fix CI build

client/config/webpack.config.prod.js

@@ -7,6 +7,7 @@ const ManifestPlugin = require('webpack-manifest-plugin');
 const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
 const eslintFormatter = require('react-dev-utils/eslintFormatter');
 const ModuleScopePlugin = require('react-dev-utils/ModuleScopePlugin');
+const TerserPlugin = require('terser-webpack-plugin');
 const paths = require('./paths');
 const getClientEnvironment = require('./env');
 
@@ -23,7 +24,7 @@ if (env.stringified['process.env'].NODE_ENV !== '"production"') {
 }
 
 // Note: defined here because it will be used more than once.
-const cssFilename = 'static/css/[name].[contenthash:8].css';
+const cssFilename = 'static/css/[name].[hash:8].css';
 
 // ExtractTextPlugin expects the build output to be flat.
 // (See https://github.com/webpack-contrib/extract-text-webpack-plugin/issues/27)
@@ -35,6 +36,7 @@ const extractTextPluginOptions = {};
 // It compiles slowly and is focused on producing a fast and minimal bundle.
 // The development configuration is different and lives in a separate file.
 module.exports = {
+  mode: process.env.NODE_ENV,
   // Don't attempt to continue if there are any errors.
   bail: true,
   // We generate sourcemaps in production. This is slow but gives good results.
@@ -51,7 +53,7 @@ module.exports = {
     filename: 'static/js/[name].[chunkhash:8].js',
     chunkFilename: 'static/js/[name].[chunkhash:8].chunk.js',
     // We inferred the "public path" (such as / or /my-project) from homepage.
-    publicPath: publicPath,
+    publicPath,
     // Point sourcemap entries to original disk location (format as URL on Windows)
     devtoolModuleFilenameTemplate: info => path.relative(paths.appSrc, info.absoluteResourcePath).replace(/\\/g, '/'),
   },
@@ -62,7 +64,7 @@ module.exports = {
     // https://github.com/facebookincubator/create-react-app/issues/253
     modules: ['node_modules', paths.appNodeModules].concat(
       // It is guaranteed to exist because we tweak it in `env.js`
-      process.env.NODE_PATH.split(path.delimiter).filter(Boolean)
+      process.env.NODE_PATH.split(path.delimiter).filter(Boolean),
     ),
     // These are the reasonable defaults supported by the Node ecosystem.
     // We also include JSX as a common component filename extension to support
@@ -195,8 +197,8 @@ module.exports = {
                 },
               ],
             },
-            extractTextPluginOptions
-          )
+            extractTextPluginOptions,
+          ),
         ),
         // Note: this won't work without `new ExtractTextPlugin()` in `plugins`.
       },
@@ -204,11 +206,24 @@ module.exports = {
       // Remember to add the new extension(s) to the "file" loader exclusion list.
     ],
   },
+  optimization: {
+    minimizer: [
+      new TerserPlugin({
+        cache: true,
+        parallel: true,
+        sourceMap: true,
+      }),
+    ],
+  },
+  performance: {
+    // TODO: Add code-splitting and re-enable this when the bundle is smaller
+    hints: false,
+  },
   plugins: [
     // Makes some environment variables available in index.html.
     // The base URI is available as %BASE_URI% in index.html, e.g.:
     // <link rel="shortcut icon" href="%BASE_URI%/favicon.ico">
-    new InterpolateHtmlPlugin(env.raw),
+    new InterpolateHtmlPlugin(HtmlWebpackPlugin, env.raw),
     // Generates an `index.html` file with the <script> injected.
     new HtmlWebpackPlugin({
       inject: true,
@@ -231,24 +246,6 @@ module.exports = {
     // It is absolutely essential that NODE_ENV was set to production here.
     // Otherwise React will be compiled in the very slow development mode.
     new webpack.DefinePlugin(env.stringified),
-    // Minify the code.
-    new webpack.optimize.UglifyJsPlugin({
-      compress: {
-        warnings: false,
-        // Disabled because of an issue with Uglify breaking seemingly valid code:
-        // https://github.com/facebookincubator/create-react-app/issues/2376
-        // Pending further investigation:
-        // https://github.com/mishoo/UglifyJS2/issues/2011
-        comparisons: false,
-      },
-      output: {
-        comments: false,
-        // Turned on because emoji and regex is not minified properly using default
-        // https://github.com/facebookincubator/create-react-app/issues/2488
-        ascii_only: true,
-      },
-      sourceMap: true,
-    }),
     // Note: this won't work without ExtractTextPlugin.extract(..) in `loaders`.
     new ExtractTextPlugin({
       filename: cssFilename,