Switch to node-sass (from node-sass-chokidar)

It looks like `node-sass-chokidar` doesn't play as nicely with npm
SCSS modules like Bourbon, so we're switching it out in favor of
the base node-sass.

The chokidar version won't work with paths.js, since you have to
pass the include paths as arguments to the script in package.json.

This makes sense, but the main reason for not using the base node-sass
was apparently [a problem with Mac + docker](facebook/create-react-app#1986)
which for better or wose is not at play in my dev environment.

config/env.js

@@ -0,0 +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.
+const REACT_APP = /^REACT_APP_/i;
+
+function getClientEnvironment(publicUrl) {
+  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,
+      }
+    );
+  // Stringify all values so we can feed into Webpack DefinePlugin
+  const stringified = {
+    'process.env': Object.keys(raw).reduce((env, key) => {
+      env[key] = JSON.stringify(raw[key]);
+      return env;
+    }, {}),
+  };
+
+  return { raw, stringified };
+}
+
+module.exports = getClientEnvironment;

config/jest/cssTransform.js

@@ -0,0 +1,14 @@
+'use strict';
+
+// This is a custom Jest transformer turning style imports into empty objects.
+// http://facebook.github.io/jest/docs/tutorial-webpack.html
+
+module.exports = {
+  process() {
+    return 'module.exports = {};';
+  },
+  getCacheKey() {
+    // The output is always the same.
+    return 'cssTransform';
+  },
+};

config/jest/fileTransform.js

@@ -0,0 +1,12 @@
+'use strict';
+
+const path = require('path');
+
+// This is a custom Jest transformer turning file imports into filenames.
+// http://facebook.github.io/jest/docs/tutorial-webpack.html
+
+module.exports = {
+  process(src, filename) {
+    return `module.exports = ${JSON.stringify(path.basename(filename))};`;
+  },
+};

config/paths.js

@@ -0,0 +1,58 @@
+'use strict';
+
+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
+const appDirectory = fs.realpathSync(process.cwd());
+const resolveApp = relativePath => path.resolve(appDirectory, relativePath);
+
+const envPublicUrl = process.env.PUBLIC_URL;
+
+function ensureSlash(path, needsSlash) {
+  const hasSlash = path.endsWith('/');
+  if (hasSlash && !needsSlash) {
+    return path.substr(path, path.length - 1);
+  } else if (!hasSlash && needsSlash) {
+    return `${path}/`;
+  } else {
+    return path;
+  }
+}
+
+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.
+// Webpack needs to know it to put the right <script> hrefs into HTML even in
+// single-page apps that may serve index.html for nested URLs like /todos/42.
+// 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) {
+  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'),
+  appIndexJs: resolveApp('src/index.js'),
+  appPackageJson: resolveApp('package.json'),
+  appSrc: resolveApp('src'),
+  yarnLockFile: resolveApp('yarn.lock'),
+  testsSetup: resolveApp('src/setupTests.js'),
+  appNodeModules: resolveApp('node_modules'),
+  publicUrl: getPublicUrl(resolveApp('package.json')),
+  servedPath: getServedPath(resolveApp('package.json')),
+  // Project additions
+  bourbon: require('bourbon').includePaths,
+  bourbonNeat: require('bourbon-neat').includePaths,
+};

config/polyfills.js

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+'use strict';
+
+if (typeof Promise === 'undefined') {
+  // Rejection tracking prevents a common issue where React gets into an
+  // inconsistent state due to an error, but it gets swallowed by a Promise,
+  // and the user has no idea what causes React's erratic future behavior.
+  require('promise/lib/rejection-tracking').enable();
+  window.Promise = require('promise/lib/es6-extensions.js');
+}
+
+// fetch() polyfill for making API calls.
+require('whatwg-fetch');
+
+// Object.assign() is commonly used with React.
+// It will use the native implementation if it's present and isn't buggy.
+Object.assign = require('object-assign');