Update to appropriate test case.

src/components/screen/Intro.tsx

@@ -107,7 +107,7 @@ interface IState {
 class Page extends Component<IProps, IState> {
   private timer: any;
 
-  constructor(props) {
+  constructor(props: IProps) {
     super(props);
     this.state = {
       isLoggingIn: false,

src/components/screen/__tests__/Intro.test.tsx

@@ -6,6 +6,9 @@ import appStore from '../../../stores/appStore';
 
 // Note: test renderer must be required after react-native.
 import renderer, { ReactTestRenderer, ReactTestRendererJSON } from 'react-test-renderer';
+import * as ShallowRenderer from 'react-test-renderer/shallow';
+import User from '../../../models/User';
+import { Provider } from 'mobx-react/native';
 
 const props = {
   store: appStore,
@@ -23,41 +26,45 @@ describe('Intro page DOM rendering test', () => {
     tree = renderer.create(component).toJSON();
     expect(tree).toMatchSnapshot();
   });
+
+  it('shallow renders match snapshot', () => {
+    const shallow = ShallowRenderer.createRenderer();
+    const result = shallow.render(component);
+    expect(result).toMatchSnapshot();
+  });
 });
 
 describe('Interaction', () => {
   let rendered: any;
   let root: ReactTestRenderer['root'] | any;
-  const component = <Intro { ...props }/>;
+  const component = (
+    <Intro { ...props }/>
+  );
 
   beforeEach(() => {
     rendered = renderer.create(component);
     root = rendered.root;
   });
 
   it('simulate click', () => {
-    // root.instance.state = {
-    //   isLoggingIn: false,
-    // };
-
     jest.useFakeTimers();
-    // const spy = jest.spyOn(instance.getInstance(), 'onLogin');
+    const spy = jest.spyOn(root.instance.wrappedInstance, 'onLogin');
     const buttons = root.findAllByType(Button);
-    buttons[0].props.onPress();
+    root.instance.wrappedInstance.onLogin(); // == buttons[0].props.onPress();
     expect(setTimeout).toHaveBeenCalledTimes(1);
-    // expect(rendered.getInstance().state.isLoggingIn).toEqual(true);
+    expect(root.instance.wrappedInstance.state.isLoggingIn).toEqual(true);
+
     jest.runAllTimers();
-    // expect(rendered.getInstance().state.isLoggingIn).toEqual(false);
+    expect(root.instance.wrappedInstance.state.isLoggingIn).toEqual(false);
     expect(props.store.user.displayName).toEqual('dooboolab');
     expect(props.store.user.age).toEqual(30);
     expect(props.store.user.job).toEqual('developer');
-    // expect(spy).toBeCalled();
     buttons[1].props.onPress();
+    expect(spy).toHaveBeenCalled();
     expect(props.navigation.navigate).toBeCalledWith('Temp');
   });
 
-  // it('clearTimeout on componentWillUnmount', async  () => {
-  //   await rendered.getInstance().componentWillUnmount();
-  //   expect(clearTimeout).toBeCalled();
-  // });
+  it('componentWillUnmount', () => {
+    rendered.unmount();
+  });
 });

src/components/screen/__tests__/__snapshots__/Intro.test.tsx.snap

@@ -168,3 +168,22 @@ exports[`Intro page DOM rendering test component and snapshot matches 1`] = `
   </View>
 </View>
 `;
+
+exports[`Intro page DOM rendering test shallow renders match snapshot 1`] = `
+<Page
+  navigation={
+    Object {
+      "navigate": [MockFunction],
+    }
+  }
+  store={
+    ObservableListStore {
+      "_user": User {
+        "_age": undefined,
+        "_displayName": undefined,
+        "_job": undefined,
+      },
+    }
+  }
+/>
+`;