react/packages/react-native-renderer/src/__tests__/ReactNativeMount-test.internal.js

/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @emails react-core
 * @jest-environment node
 */

'use strict';

let React;
let ReactNative;
let createReactNativeComponentClass;
let UIManager;

describe('ReactNative', () => {
  beforeEach(() => {
    jest.resetModules();

    React = require('react');
    ReactNative = require('react-native-renderer');
    UIManager = require('UIManager');
    createReactNativeComponentClass = require('ReactNativeViewConfigRegistry')
      .register;
  });

  it('should be able to create and render a native component', () => {
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {foo: true},
      uiViewClassName: 'RCTView',
    }));

    ReactNative.render(<View foo="test" />, 1);
    expect(UIManager.createView).toBeCalled();
    expect(UIManager.setChildren).toBeCalled();
    expect(UIManager.manageChildren).not.toBeCalled();
    expect(UIManager.updateView).not.toBeCalled();
  });

  it('should be able to create and update a native component', () => {
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {foo: true},
      uiViewClassName: 'RCTView',
    }));

    ReactNative.render(<View foo="foo" />, 11);

    expect(UIManager.createView).toHaveBeenCalledTimes(1);
    expect(UIManager.setChildren).toHaveBeenCalledTimes(1);
    expect(UIManager.manageChildren).not.toBeCalled();
    expect(UIManager.updateView).not.toBeCalled();

    ReactNative.render(<View foo="bar" />, 11);

    expect(UIManager.createView).toHaveBeenCalledTimes(1);
    expect(UIManager.setChildren).toHaveBeenCalledTimes(1);
    expect(UIManager.manageChildren).not.toBeCalled();
    expect(UIManager.updateView).toBeCalledWith(3, 'RCTView', {foo: 'bar'});
  });

  it('should not call UIManager.updateView after render for properties that have not changed', () => {
    const Text = createReactNativeComponentClass('RCTText', () => ({
      validAttributes: {foo: true},
      uiViewClassName: 'RCTText',
    }));

    ReactNative.render(<Text foo="a">1</Text>, 11);
    expect(UIManager.updateView).not.toBeCalled();

    // If no properties have changed, we shouldn't call updateView.
    ReactNative.render(<Text foo="a">1</Text>, 11);
    expect(UIManager.updateView).not.toBeCalled();

    // Only call updateView for the changed property (and not for text).
    ReactNative.render(<Text foo="b">1</Text>, 11);
    expect(UIManager.updateView).toHaveBeenCalledTimes(1);

    // Only call updateView for the changed text (and no other properties).
    ReactNative.render(<Text foo="b">2</Text>, 11);
    expect(UIManager.updateView).toHaveBeenCalledTimes(2);

    // Call updateView for both changed text and properties.
    ReactNative.render(<Text foo="c">3</Text>, 11);
    expect(UIManager.updateView).toHaveBeenCalledTimes(4);
  });

  it('should not call UIManager.updateView from setNativeProps for properties that have not changed', () => {
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {foo: true},
      uiViewClassName: 'RCTView',
    }));

    class Subclass extends ReactNative.NativeComponent {
      render() {
        return <View />;
      }
    }

    [View, Subclass].forEach(Component => {
      UIManager.updateView.mockReset();

      let viewRef;
      ReactNative.render(
        <Component
          foo="bar"
          ref={ref => {
            viewRef = ref;
          }}
        />,
        11,
      );
      expect(UIManager.updateView).not.toBeCalled();

      viewRef.setNativeProps({});
      expect(UIManager.updateView).not.toBeCalled();

      viewRef.setNativeProps({foo: 'baz'});
      expect(UIManager.updateView).toHaveBeenCalledTimes(1);
    });
  });

  it('returns the correct instance and calls it in the callback', () => {
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {foo: true},
      uiViewClassName: 'RCTView',
    }));

    let a;
    let b;
    const c = ReactNative.render(
      <View foo="foo" ref={v => (a = v)} />,
      11,
      function() {
        b = this;
      },
    );

    expect(a).toBeTruthy();
    expect(a).toBe(b);
    expect(a).toBe(c);
  });

  it('renders and reorders children', () => {
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {title: true},
      uiViewClassName: 'RCTView',
    }));

    class Component extends React.Component {
      render() {
        const chars = this.props.chars.split('');
        return (
          <View>{chars.map(text => <View key={text} title={text} />)}</View>
        );
      }
    }

    // Mini multi-child stress test: lots of reorders, some adds, some removes.
    const before = 'abcdefghijklmnopqrst';
    const after = 'mxhpgwfralkeoivcstzy';

    ReactNative.render(<Component chars={before} />, 11);
    expect(UIManager.__dumpHierarchyForJestTestsOnly()).toMatchSnapshot();

    ReactNative.render(<Component chars={after} />, 11);
    expect(UIManager.__dumpHierarchyForJestTestsOnly()).toMatchSnapshot();
  });

  it('calls setState with no arguments', () => {
    let mockArgs;
    class Component extends React.Component {
      componentDidMount() {
        this.setState({}, (...args) => (mockArgs = args));
      }
      render() {
        return false;
      }
    }

    ReactNative.render(<Component />, 11);
    expect(mockArgs.length).toEqual(0);
  });

  it('should throw when <View> is used inside of a <Text> ancestor', () => {
    const Image = createReactNativeComponentClass('RCTImage', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTImage',
    }));
    const Text = createReactNativeComponentClass('RCTText', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTText',
    }));
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTView',
    }));

    expect(() =>
      ReactNative.render(
        <Text>
          <View />
        </Text>,
        11,
      ),
    ).toThrow('Nesting of <View> within <Text> is not currently supported.');

    // Non-View things (e.g. Image) are fine
    ReactNative.render(
      <Text>
        <Image />
      </Text>,
      11,
    );
  });

  it('should throw for text not inside of a <Text> ancestor', () => {
    const ScrollView = createReactNativeComponentClass('RCTScrollView', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTScrollView',
    }));
    const Text = createReactNativeComponentClass('RCTText', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTText',
    }));
    const View = createReactNativeComponentClass('RCTView', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTView',
    }));

    expect(() => ReactNative.render(<View>this should warn</View>, 11)).toThrow(
      'Text strings must be rendered within a <Text> component.',
    );

    expect(() =>
      ReactNative.render(
        <Text>
          <ScrollView>hi hello hi</ScrollView>
        </Text>,
        11,
      ),
    ).toThrow('Text strings must be rendered within a <Text> component.');
  });

  it('should not throw for text inside of an indirect <Text> ancestor', () => {
    const Text = createReactNativeComponentClass('RCTText', () => ({
      validAttributes: {},
      uiViewClassName: 'RCTText',
    }));

    const Indirection = () => 'Hi';

    ReactNative.render(
      <Text>
        <Indirection />
      </Text>,
      11,
    );
  });
});