Update create-react-app scripts

config/env.js

@@ -1,35 +1,90 @@
 'use strict';
 
+const fs = require('fs');
+const path = require('path');
+const paths = require('./paths');
+
+// Make sure that including paths.js after env.js will read .env variables.
+delete require.cache[require.resolve('./paths')];
+
+const NODE_ENV = process.env.NODE_ENV;
+if (!NODE_ENV) {
+  throw new Error(
+    'The NODE_ENV environment variable is required but was not specified.'
+  );
+}
+
+// https://github.com/bkeepers/dotenv#what-other-env-files-can-i-use
+var dotenvFiles = [
+  `${paths.dotenv}.${NODE_ENV}.local`,
+  `${paths.dotenv}.${NODE_ENV}`,
+  // Don't include `.env.local` for `test` environment
+  // since normally you expect tests to produce the same
+  // results for everyone
+  NODE_ENV !== 'test' && `${paths.dotenv}.local`,
+  paths.dotenv,
+].filter(Boolean);
+
+// Load environment variables from .env* files. Suppress warnings using silent
+// if this file is missing. dotenv will never modify any environment variables
+// that have already been set.
+// https://github.com/motdotla/dotenv
+dotenvFiles.forEach(dotenvFile => {
+  if (fs.existsSync(dotenvFile)) {
+    require('dotenv').config({
+      path: dotenvFile,
+    });
+  }
+});
+
+// We support resolving modules according to `NODE_PATH`.
+// This lets you use absolute paths in imports inside large monorepos:
+// https://github.com/facebookincubator/create-react-app/issues/253.
+// It works similar to `NODE_PATH` in Node itself:
+// https://nodejs.org/api/modules.html#modules_loading_from_the_global_folders
+// Note that unlike in Node, only *relative* paths from `NODE_PATH` are honored.
+// Otherwise, we risk importing Node.js core modules into an app instead of Webpack shims.
+// https://github.com/facebookincubator/create-react-app/issues/1023#issuecomment-265344421
+// We also resolve them to make sure all tools using them work consistently.
+const appDirectory = fs.realpathSync(process.cwd());
+process.env.NODE_PATH = (process.env.NODE_PATH || '')
+  .split(path.delimiter)
+  .filter(folder => folder && !path.isAbsolute(folder))
+  .map(folder => path.resolve(appDirectory, folder))
+  .join(path.delimiter);
+
 // Grab NODE_ENV and REACT_APP_* environment variables and prepare them to be
 // injected into the application via DefinePlugin in Webpack configuration.
-
-var REACT_APP = /^REACT_APP_/i;
+const REACT_APP = /^REACT_APP_/i;
 
 function getClientEnvironment(publicUrl) {
-  var raw = Object
-    .keys(process.env)
+  const raw = Object.keys(process.env)
     .filter(key => REACT_APP.test(key))
-    .reduce((env, key) => {
-      env[key] = process.env[key];
-      return env;
-    }, {
-      // Useful for determining whether we’re running in production mode.
-      // Most importantly, it switches React into the correct mode.
-      'NODE_ENV': process.env.NODE_ENV || 'development',
-      // Useful for resolving the correct path to static assets in `public`.
-      // For example, <img src={process.env.PUBLIC_URL + '/img/logo.png'} />.
-      // This should only be used as an escape hatch. Normally you would put
-      // images into the `src` and `import` them in code to get their paths.
-      'PUBLIC_URL': publicUrl
-    });
+    .reduce(
+      (env, key) => {
+        env[key] = process.env[key];
+        return env;
+      },
+      {
+        // Useful for determining whether we’re running in production mode.
+        // Most importantly, it switches React into the correct mode.
+        NODE_ENV: process.env.NODE_ENV || 'development',
+        // Useful for resolving the correct path to static assets in `public`.
+        // For example, <img src={process.env.PUBLIC_URL + '/img/logo.png'} />.
+        // This should only be used as an escape hatch. Normally you would put
+        // images into the `src` and `import` them in code to get their paths.
+        PUBLIC_URL: publicUrl,
+      }
+    );
   // Stringify all values so we can feed into Webpack DefinePlugin
-  var stringified = {
-    'process.env': Object
-      .keys(raw)
-      .reduce((env, key) => {
+  const stringified = {
+    'process.env': Object.keys(raw).reduce(
+      (env, key) => {
         env[key] = JSON.stringify(raw[key]);
         return env;
-      }, {})
+      },
+      {}
+    ),
   };
 
   return { raw, stringified };

config/jest/fileTransform.js

@@ -7,6 +7,6 @@ const path = require('path');
 
 module.exports = {
   process(src, filename) {
-    return 'module.exports = ' + JSON.stringify(path.basename(filename)) + ';';
+    return `module.exports = ${JSON.stringify(path.basename(filename))};`;
   },
 };

config/paths.js

@@ -1,53 +1,29 @@
 'use strict';
 
-var path = require('path');
-var fs = require('fs');
-var url = require('url');
+const path = require('path');
+const fs = require('fs');
+const url = require('url');
 
 // Make sure any symlinks in the project folder are resolved:
 // https://github.com/facebookincubator/create-react-app/issues/637
-var appDirectory = fs.realpathSync(process.cwd());
-function resolveApp(relativePath) {
-  return path.resolve(appDirectory, relativePath);
-}
-
-// We support resolving modules according to `NODE_PATH`.
-// This lets you use absolute paths in imports inside large monorepos:
-// https://github.com/facebookincubator/create-react-app/issues/253.
-
-// It works similar to `NODE_PATH` in Node itself:
-// https://nodejs.org/api/modules.html#modules_loading_from_the_global_folders
-
-// We will export `nodePaths` as an array of absolute paths.
-// It will then be used by Webpack configs.
-// Jest doesn’t need this because it already handles `NODE_PATH` out of the box.
+const appDirectory = fs.realpathSync(process.cwd());
+const resolveApp = relativePath => path.resolve(appDirectory, relativePath);
 
-// Note that unlike in Node, only *relative* paths from `NODE_PATH` are honored.
-// Otherwise, we risk importing Node.js core modules into an app instead of Webpack shims.
-// https://github.com/facebookincubator/create-react-app/issues/1023#issuecomment-265344421
-
-var nodePaths = (process.env.NODE_PATH || '')
-  .split(process.platform === 'win32' ? ';' : ':')
-  .filter(Boolean)
-  .filter(folder => !path.isAbsolute(folder))
-  .map(resolveApp);
-
-var envPublicUrl = process.env.PUBLIC_URL;
+const envPublicUrl = process.env.PUBLIC_URL;
 
 function ensureSlash(path, needsSlash) {
-  var hasSlash = path.endsWith('/');
+  const hasSlash = path.endsWith('/');
   if (hasSlash && !needsSlash) {
     return path.substr(path, path.length - 1);
   } else if (!hasSlash && needsSlash) {
-    return path + '/';
+    return `${path}/`;
   } else {
     return path;
   }
 }
 
-function getPublicUrl(appPackageJson) {
-  return envPublicUrl || require(appPackageJson).homepage;
-}
+const getPublicUrl = appPackageJson =>
+  envPublicUrl || require(appPackageJson).homepage;
 
 // We use `PUBLIC_URL` environment variable or "homepage" field to infer
 // "public path" at which the app is served.
@@ -56,15 +32,15 @@ function getPublicUrl(appPackageJson) {
 // We can't use a relative path in HTML because we don't want to load something
 // like /todos/42/static/js/bundle.7289d.js. We have to know the root.
 function getServedPath(appPackageJson) {
-  var publicUrl = getPublicUrl(appPackageJson);
-  var servedUrl = envPublicUrl || (
-    publicUrl ? url.parse(publicUrl).pathname : '/'
-  );
+  const publicUrl = getPublicUrl(appPackageJson);
+  const servedUrl = envPublicUrl ||
+    (publicUrl ? url.parse(publicUrl).pathname : '/');
   return ensureSlash(servedUrl, true);
 }
 
 // config after eject: we're in ./config/
 module.exports = {
+  dotenv: resolveApp('.env'),
   appBuild: resolveApp('build'),
   appPublic: resolveApp('public'),
   appHtml: resolveApp('public/index.html'),
@@ -74,7 +50,6 @@ module.exports = {
   yarnLockFile: resolveApp('yarn.lock'),
   testsSetup: resolveApp('src/setupTests.js'),
   appNodeModules: resolveApp('node_modules'),
-  nodePaths: nodePaths,
   publicUrl: getPublicUrl(resolveApp('package.json')),
-  servedPath: getServedPath(resolveApp('package.json'))
+  servedPath: getServedPath(resolveApp('package.json')),
 };