Applied coding styles to scripts

scripts/start.js

@@ -1,4 +1,4 @@
-'use strict';
+/* eslint no-console: "off" */
 
 // Do this as the first thing so that any code reading it knows the right env.
 process.env.BABEL_ENV = 'development';
@@ -7,7 +7,7 @@ process.env.NODE_ENV = 'development';
 // Makes the script crash on unhandled rejections instead of silently
 // ignoring them. In the future, promise rejections that are not handled will
 // terminate the Node.js process with a non-zero exit code.
-process.on('unhandledRejection', err => {
+process.on('unhandledRejection', (err) => {
   throw err;
 });
 
@@ -35,12 +35,13 @@ const useYarn = fs.existsSync(paths.yarnLockFile);
 const isInteractive = process.stdout.isTTY;
 
 // Warn and crash if required files are missing
-if (!checkRequiredFiles([paths.appHtml, paths.appIndexJs])) {
+if (!checkRequiredFiles([ paths.appHtml, paths.appIndexJs ])) {
   process.exit(1);
 }
 
 // Tools like Cloud9 rely on this.
-const DEFAULT_PORT = parseInt(process.env.PORT, 10) || 3000;
+const FALLBACK_PORT = 3000;
+const DEFAULT_PORT = parseInt(process.env.PORT, 10) || FALLBACK_PORT;
 const HOST = process.env.HOST || '0.0.0.0';
 
 if (process.env.HOST) {
@@ -52,7 +53,7 @@ if (process.env.HOST) {
     )
   );
   console.log(
-    `If this was unintentional, check that you haven't mistakenly set it in your shell.`
+    'If this was unintentional, check that you haven\'t mistakenly set it in your shell.'
   );
   console.log(`Learn more here: ${chalk.yellow('http://bit.ly/2mwWSwH')}`);
   console.log();
@@ -61,47 +62,59 @@ if (process.env.HOST) {
 // We attempt to use the default port but if it is busy, we offer the user to
 // run on a different port. `choosePort()` Promise resolves to the next free port.
 choosePort(HOST, DEFAULT_PORT)
-  .then(port => {
-    if (port == null) {
+  .then((port) => {
+    if (port === null) {
       // We have not found a port.
       return;
     }
+
     const protocol = process.env.HTTPS === 'true' ? 'https' : 'http';
     const appName = require(paths.appPackageJson).name;
+
     const urls = prepareUrls(protocol, HOST, port);
+
     // Create a webpack compiler that is configured with custom messages.
     const compiler = createCompiler(webpack, config, appName, urls, useYarn);
+
     // Load proxy config
     const proxySetting = require(paths.appPackageJson).proxy;
+
     const proxyConfig = prepareProxy(proxySetting, paths.appPublic);
+
     // Serve webpack assets generated by the compiler over a web sever.
     const serverConfig = createDevServerConfig(
       proxyConfig,
       urls.lanUrlForConfig
     );
     const devServer = new WebpackDevServer(compiler, serverConfig);
+
     // Launch WebpackDevServer.
-    devServer.listen(port, HOST, err => {
+
+    devServer.listen(port, HOST, (err) => {
       if (err) {
-        return console.log(err);
+        console.log(err);
+
+        return;
       }
       if (isInteractive) {
         clearConsole();
       }
+
       console.log(chalk.cyan('Starting the development server...\n'));
       openBrowser(urls.localUrlForBrowser);
     });
 
-    ['SIGINT', 'SIGTERM'].forEach(function(sig) {
-      process.on(sig, function() {
+    [ 'SIGINT', 'SIGTERM' ].forEach((sig) => {
+      process.on(sig, () => {
         devServer.close();
         process.exit();
       });
     });
   })
-  .catch(err => {
+  .catch((err) => {
     if (err && err.message) {
       console.log(err.message);
     }
+
     process.exit(1);
   });