refactor: remove the features option (#2604)

BREAKING CHANGE: the `features` option was removed

Author: evilebottnawi

lib/Server.js

@@ -508,7 +508,7 @@ class Server {
       runnableFeatures.push('onAfterSetupMiddleware');
     }
 
-    (this.options.features || runnableFeatures).forEach((feature) => {
+    runnableFeatures.forEach((feature) => {
       features[feature]();
     });
   }

lib/options.json

@@ -87,12 +87,6 @@
     "disableHostCheck": {
       "type": "boolean"
     },
-    "features": {
-      "type": "array",
-      "items": {
-        "type": "string"
-      }
-    },
     "fs": {
       "type": "object"
     },
@@ -431,7 +425,6 @@
       "compress": "should be {Boolean} (https://webpack.js.org/configuration/dev-server/#devservercompress)",
       "contentBase": "should be {Number|String|Array} (https://webpack.js.org/configuration/dev-server/#devservercontentbase)",
       "disableHostCheck": "should be {Boolean} (https://webpack.js.org/configuration/dev-server/#devserverdisablehostcheck)",
-      "features": "should be {Array}",
       "fs": "should be {Object} (https://github.com/webpack/webpack-dev-middleware#fs)",
       "headers": "should be {Object} (https://webpack.js.org/configuration/dev-server/#devserverheaders-)",
       "historyApiFallback": "should be {Boolean|Object} (https://webpack.js.org/configuration/dev-server/#devserverhistoryapifallback)",

test/__snapshots__/Validation.test.js.snap

@@ -37,5 +37,5 @@ exports[`Validation validation should fail validation for invalid \`writeToDisk\
 exports[`Validation validation should fail validation for no additional properties 1`] = `
 "Invalid configuration object. Object has been initialized using a configuration object that does not match the API schema.
  - configuration has an unknown property 'additional'. These properties are valid:
-   object { allowedHosts?, bonjour?, clientLogLevel?, clientOptions?, compress?, contentBasePublicPath?, contentBase?, disableHostCheck?, features?, fs?, headers?, historyApiFallback?, host?, hot?, http2?, https?, index?, injectClient?, injectHot?, liveReload?, log?, logLevel?, logTime?, mimeTypes?, noInfo?, onAfterSetupMiddleware?, onBeforeSetupMiddleware?, onListening?, open?, openPage?, overlay?, port?, profile?, progress?, proxy?, public?, publicPath?, quiet?, reporter?, requestCert?, serveIndex?, serverSideRender?, socket?, staticOptions?, stats?, transportMode?, useLocalIp?, warn?, watchContentBase?, watchOptions?, writeToDisk? }"
+   object { allowedHosts?, bonjour?, clientLogLevel?, clientOptions?, compress?, contentBasePublicPath?, contentBase?, disableHostCheck?, fs?, headers?, historyApiFallback?, host?, hot?, http2?, https?, index?, injectClient?, injectHot?, liveReload?, log?, logLevel?, logTime?, mimeTypes?, noInfo?, onAfterSetupMiddleware?, onBeforeSetupMiddleware?, onListening?, open?, openPage?, overlay?, port?, profile?, progress?, proxy?, public?, publicPath?, quiet?, reporter?, requestCert?, serveIndex?, serverSideRender?, socket?, staticOptions?, stats?, transportMode?, useLocalIp?, warn?, watchContentBase?, watchOptions?, writeToDisk? }"
 `;

test/options.test.js

@@ -215,10 +215,6 @@ describe('options', () => {
         success: [true],
         failure: [''],
       },
-      features: {
-        success: [['onBeforeSetupMiddleware', 'onAfterSetupMiddleware'], []],
-        failure: [false],
-      },
       fs: {
         success: [
           {