Added a small test for the App component

Author: rscarvalho

ui/package.json

@@ -14,6 +14,8 @@
     "redux-actions": "^2.2.1"
   },
   "devDependencies": {
+    "enzyme": "^3.1.1",
+    "enzyme-adapter-react-16": "^1.0.4",
     "eslint-config-react-app": "^2.0.1"
   },
   "scripts": {

ui/src/components/__tests__/App.spec.js

@@ -0,0 +1,12 @@
+import App from '../App';
+import NavBar from '../NavBar';
+import React from 'react';
+import { shallow } from 'enzyme';
+
+describe('components/App', () => {
+  it('renders the NavBar', () => {
+    const wrapper = shallow(<App />);
+
+    expect(wrapper.find(NavBar)).toHaveLength(1);
+  });
+});

ui/src/setupTests.js

@@ -0,0 +1,4 @@
+import Adapter from 'enzyme-adapter-react-16';
+import { configure } from 'enzyme';
+
+configure({ adapter: new Adapter() });