old_contents: import React from 'react';
  import { mount } from 'enzyme';
  import MountInApp from './';
  import TestUtils from 'react/lib/ReactTestUtils';
  
  describe('MountInApp', () => {
    let instance, placeholder;
  
    function renderComponent() {
      placeholder = TestUtils.renderIntoDocument(<div/>);
  
      instance = mount(<MountInApp targetId="say_hello_here">
        <div>Hello!!</div>
      </MountInApp>);
    }
  
    describe('if the target element does not exist', () => {
      beforeEach(() => {
        renderComponent();
      });
      it("doesn't mount anything inside of the placeholder", () => {
        expect(placeholder.children.length).toEqual(0);
      });
    });
  
    describe('if the target element exists', () => {
      beforeEach(() => {
        spyOn(document, 'getElementById').and.callFake((elementId) => {
          return (elementId == 'say_hello_here') ? placeholder : null;
        });
  
        renderComponent();
      });
  
      it('mounts the specified children in the placeholder', () => {
        expect(placeholder.children.length).toEqual(1);
  
        let wrapperDiv = placeholder.children[0];
        expect(wrapperDiv.tagName).toEqual('DIV');
        expect(wrapperDiv.className).toEqual('carbon-mount-in-app');
        expect(wrapperDiv.children.length).toEqual(1);
  
        let contentDiv = wrapperDiv.children[0];
        expect(contentDiv.tagName).toEqual('DIV');
        expect(contentDiv.textContent).toEqual('Hello!!');
      });
    });
  
  });
  
  
new_contents: import React from 'react';
  import { mount } from 'enzyme';
  import MountInApp from './';
  import TestUtils from 'react/lib/ReactTestUtils';
  
  describe('MountInApp', () => {
    let instance, placeholder;
  
    function renderComponent() {
      placeholder = TestUtils.renderIntoDocument(<div/>);
  
      instance = mount(<MountInApp targetId="say_hello_here">
        <div>Hello!!</div>
      </MountInApp>);
    }
  
    describe('if the target element does not exist', () => {
      beforeEach(() => {
        renderComponent();
      });
      it("doesn't mount anything inside of the placeholder", () => {
        expect(placeholder.children.length).toEqual(0);
      });
    });
  
    describe('if the target element exists', () => {
      beforeEach(() => {
        spyOn(document, 'getElementById').and.callFake((elementId) => {
          return (elementId === 'say_hello_here') ? placeholder : null;
        });
  
        renderComponent();
      });
  
      it('mounts the specified children in the placeholder', () => {
        expect(placeholder.children.length).toEqual(1);
  
        let wrapperDiv = placeholder.children[0];
        expect(wrapperDiv.tagName).toEqual('DIV');
        expect(wrapperDiv.className).toEqual('carbon-mount-in-app');
        expect(wrapperDiv.children.length).toEqual(1);
  
        let contentDiv = wrapperDiv.children[0];
        expect(contentDiv.tagName).toEqual('DIV');
        expect(contentDiv.textContent).toEqual('Hello!!');
      });
    });
  
  });
  
  
subject: address double equals comment