Rewrite frontend using create-react-app

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)) + ';';
+  },
+};