add test cases CancelButton and Constants

Author: testshallpass

__tests__/CancelButton-test.js

@@ -4,8 +4,18 @@ import CancelButton from '../CancelButton';
 import { shallow } from 'enzyme';
 import toJson from 'enzyme-to-json';
 
-test('CancelButton renders', () => {
-  const wrapper = shallow(<CancelButton />);
-  const tree = toJson(wrapper);
-  expect(tree).toMatchSnapshot();
-});
+describe('CancelButton', () => {
+  test('renders', () => {
+    const wrapper = shallow(<CancelButton />);
+    const tree = toJson(wrapper);
+    expect(tree).toMatchSnapshot();
+  });
+  test('test onPress to be defined', () => {
+    const onCancel = () => {
+      console.log('Cancelled');
+    };
+    const wrapper = shallow(<CancelButton onPress={onCancel} />);
+    expect(wrapper.prop('onPress')).toEqual(onCancel);
+    expect(wrapper.props().onPress).toBeDefined();
+  });
+});

__tests__/Constants-test.js

@@ -1,20 +1,30 @@
 import { getDefaultStatusBarStyle, getDefaultStatusBarBackgroundColor } from '../constants';
 
-test('StatusBarDefaultBarStyle to be default', () => {
-  const barStyle = getDefaultStatusBarStyle();
-  expect(barStyle).toBe('default');
-});
-test('StatusBarDefaultBackgroundColor to be black', () => {
-  const backgroundColor = getDefaultStatusBarBackgroundColor();
-  expect(backgroundColor).toBe('black');
-});
-test('StatusBarDefaultBarStyle to be StatusBar._defaultProps.barStyle.value', () => {
-  const { StatusBar } = require('react-native');
-  const barStyle = getDefaultStatusBarStyle();
-  expect(barStyle).toBe(StatusBar._defaultProps.barStyle.value);
-});
-test('StatusBarDefaultBackgroundColor to be StatusBar._defaultProps.backgroundColor.value', () => {
-  const { StatusBar } = require('react-native');
-  const backgroundColor = getDefaultStatusBarBackgroundColor();
-  expect(backgroundColor).toBe(StatusBar._defaultProps.backgroundColor.value);
+describe('Constants', () => {
+  describe('Mock StatusBar with no _defaultProps property', () => {
+    beforeEach(() => {
+      jest.mock('StatusBar', () => {
+        return {};
+      });
+    });
+    test('StatusBarDefaultBarStyle to be default', () => {
+      const barStyle = getDefaultStatusBarStyle();
+      expect(barStyle).toBe('default');
+    });
+    test('StatusBarDefaultBackgroundColor to be black', () => {
+      const backgroundColor = getDefaultStatusBarBackgroundColor();
+      expect(backgroundColor).toBe('black');
+    });
+  });
+  describe('StatusBar with _defaultProps property', () => {
+    const { StatusBar } = require('react-native');
+    test('StatusBarDefaultBarStyle to be StatusBar._defaultProps.barStyle.value', () => {
+      const barStyle = getDefaultStatusBarStyle();
+      expect(barStyle).toBe(StatusBar._defaultProps.barStyle.value);
+    });
+    test('StatusBarDefaultBackgroundColor to be StatusBar._defaultProps.backgroundColor.value', () => {
+      const backgroundColor = getDefaultStatusBarBackgroundColor();
+      expect(backgroundColor).toBe(StatusBar._defaultProps.backgroundColor.value);
+    });
+  });
 });