Change warning to a hard error

Author: rogeriochaves

packages/react-dev-utils/WarnAboutLoaderDisablingPlugin.js renamed to packages/react-dev-utils/BlockUnsupportedWebpackLoaderSyntax.js

@@ -7,26 +7,25 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  */
 
-// This Webpack plugin warns the user when using special webpack syntax
+// This Webpack plugin forbids usage of special webpack syntax
 // to disable loaders (https://webpack.github.io/docs/loaders.html#loader-order)
 // This makes it very coupled to webpack and might break in the future.
 // See https://github.com/facebookincubator/create-react-app/issues/733.
 
 'use strict';
 
-var chalk = require('chalk');
-
-class WarnAboutLoaderDisablingPlugin {
+class BlockUnsupportedWebpackLoaderSyntax {
   apply(compiler) {
     compiler.plugin('normal-module-factory', (normalModuleFactory) => {
       normalModuleFactory.plugin('before-resolve', (data, callback) => {
+        let error = null;
         if (data.request.match(/^-?!!?/)) {
-          chalk.yellow(`Warning: You are requesting '${data.request}'. Special Webpack Loaders syntax is not officially supported and makes you code very coupled to Webpack, which might break in the future, we recommend that you remove it. See `https://github.com/facebookincubator/create-react-app/issues/733`);
+          error = `You are requesting '${data.request}'. Special Webpack Loaders syntax is not officially supported and makes you code very coupled to Webpack, which might break in the future, we recommend that you remove it. See https://github.com/facebookincubator/create-react-app/issues/733`;
         }
-        callback(null, data);
-      })
+        callback(error, data);
+      });
     });
   }
 }
 
-module.exports = WarnAboutLoaderDisablingPlugin;
+module.exports = BlockUnsupportedWebpackLoaderSyntax;

packages/react-dev-utils/README.md

@@ -81,7 +81,7 @@ module.exports = {
 }
 ```
 
-#### `new WarnAboutDisablingPlugin()`
+#### `new BlockUnsupportedWebpackLoaderSyntax()`
 
 This Webpack plugin warns the user when using special webpack syntax for
 disabling loaders (like `!!file!./stuff`). This makes it very coupled
@@ -90,17 +90,17 @@ See [#733](https://github.com/facebookincubator/create-react-app/issues/733) for
 
 ```js
 var path = require('path');
-var WarnAboutLoaderDisablingPlugin = require('react-dev-utils/WarnAboutLoaderDisablingPlugin);
+var BlockUnsupportedWebpackLoaderSyntax = require('react-dev-utils/BlockUnsupportedWebpackLoaderSyntax');
 
 // Webpack config
 module.exports = {
   // ...
   plugins: [
     // ...
-    // This warns about using Webpack Special Loader syntax, which makes it
+    // This forbids usage of Webpack Special Loader syntax, which makes it
     // very coupled to Webpack and might break in the future.
     // See https://github.com/facebookincubator/create-react-app/issues/733
-    new WarnAboutLoaderDisablingPlugin()
+    new BlockUnsupportedWebpackLoaderSyntax()
   ],
   // ...
 }

packages/react-scripts/config/webpack.config.dev.js

@@ -17,7 +17,7 @@ var HtmlWebpackPlugin = require('html-webpack-plugin');
 var CaseSensitivePathsPlugin = require('case-sensitive-paths-webpack-plugin');
 var InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
 var WatchMissingNodeModulesPlugin = require('react-dev-utils/WatchMissingNodeModulesPlugin');
-var WarnAboutLoaderDisablingPlugin = require('react-dev-utils/WarnAboutLoaderDisablingPlugin');
+var BlockUnsupportedWebpackLoaderSyntax = require('react-dev-utils/BlockUnsupportedWebpackLoaderSyntax');
 var getClientEnvironment = require('./env');
 var paths = require('./paths');
 
@@ -217,11 +217,11 @@ module.exports = {
     // to restart the development server for Webpack to discover it. This plugin
     // makes the discovery automatic so you don't have to restart.
     // See https://github.com/facebookincubator/create-react-app/issues/186
-    new WatchMissingNodeModulesPlugin(paths.appNodeModules)
-    // This warns about using Webpack Special Loader syntax, which makes it
+    new WatchMissingNodeModulesPlugin(paths.appNodeModules),
+    // This forbids usage of Webpack Special Loader syntax, which makes it
     // very coupled to Webpack and might break in the future.
     // See https://github.com/facebookincubator/create-react-app/issues/733
-    new WarnAboutLoaderDisablingPlugin()
+    new BlockUnsupportedWebpackLoaderSyntax()
   ],
   // Some libraries import Node modules but don't use them in the browser.
   // Tell Webpack to provide empty mocks for them so importing them works.