test: get the tests to work and add a test for the initial state of t…

README.md

@@ -1,2 +1,5 @@
 ## Color Palette Contrast Analyzer
 
+## Contributing
+
+On Mac OS X, you will likely need watchman to be installed in order to get `yarn test` to run. Use Homebrew to install watchman with `brew install watchman`.

src/App.test.js

@@ -1,9 +1,9 @@
-import React from 'react';
-import ReactDOM from 'react-dom';
-import App from './App';
+import React from 'react'
+import ReactDOM from 'react-dom'
+import App from './App'
 
 it('renders without crashing', () => {
-  const div = document.createElement('div');
-  ReactDOM.render(<App />, div);
-  ReactDOM.unmountComponentAtNode(div);
-});
+  const div = document.createElement('div')
+  ReactDOM.render(<App />, div)
+  ReactDOM.unmountComponentAtNode(div)
+})

src/color-palette.test.js

@@ -0,0 +1,10 @@
+import React from 'react'
+import ReactDOM from 'react-dom'
+import ColorPalette from './color-palette'
+
+test('should render a paragraph if there are no colors', () => {
+  const div = document.createElement('div')
+  ReactDOM.render(<ColorPalette />, div)
+  expect(div.querySelectorAll('p')).toBeDefined()
+  ReactDOM.unmountComponentAtNode(div)
+})

src/setupTests.js

@@ -0,0 +1,6 @@
+const localStorageMock = {
+  getItem: jest.fn(),
+  setItem: jest.fn(),
+  clear: jest.fn()
+};
+global.localStorage = localStorageMock