RubyLouvre/anu

const React = require('react');
const ReactDOM = require('react-dom');

describe('ReactMount', () => {
  it('should destroy a react root upon request', () => {
    const mainContainerDiv = document.createElement('div');
    document.body.appendChild(mainContainerDiv);

    const instanceOne = <div className="firstReactDiv" />;
    const firstRootDiv = document.createElement('div');
    mainContainerDiv.appendChild(firstRootDiv);
    ReactDOM.render(instanceOne, firstRootDiv);

    const instanceTwo = <div className="secondReactDiv" />;
    const secondRootDiv = document.createElement('div');
    mainContainerDiv.appendChild(secondRootDiv);
    ReactDOM.render(instanceTwo, secondRootDiv);

    // Test that two react roots are rendered in isolation
    expect(firstRootDiv.firstChild.className).toBe('firstReactDiv');
    expect(secondRootDiv.firstChild.className).toBe('secondReactDiv');

    // Test that after unmounting each, they are no longer in the document.
    ReactDOM.unmountComponentAtNode(firstRootDiv);
    expect(firstRootDiv.firstChild).toBeNull();
    ReactDOM.unmountComponentAtNode(secondRootDiv);
    expect(secondRootDiv.firstChild).toBeNull();
  });

  it('should warn when unmounting a non-container root node', () => {
    const mainContainerDiv = document.createElement('div');

    const component = (
      <div>
        <div />
      </div>
    );
    ReactDOM.render(component, mainContainerDiv);

    // Test that unmounting at a root node gives a helpful warning
    const rootDiv = mainContainerDiv.firstChild;
    expect(() => ReactDOM.unmountComponentAtNode(rootDiv)).toWarnDev(
      "Warning: unmountComponentAtNode(): The node you're attempting to " +
        'unmount was rendered by React and is not a top-level container. You ' +
        'may have accidentally passed in a React root node instead of its ' +
        'container.',
    );
  });

  it('should warn when unmounting a non-container, non-root node', () => {
    const mainContainerDiv = document.createElement('div');

    const component = (
      <div>
        <div>
          <div />
        </div>
      </div>
    );
    ReactDOM.render(component, mainContainerDiv);

    // Test that unmounting at a non-root node gives a different warning
    const nonRootDiv = mainContainerDiv.firstChild.firstChild;
    expect(() => ReactDOM.unmountComponentAtNode(nonRootDiv)).toWarnDev(
      "Warning: unmountComponentAtNode(): The node you're attempting to " +
        'unmount was rendered by React and is not a top-level container. ' +
        'Instead, have the parent component update its state and rerender in ' +
        'order to remove this component.',
    );
  });
});