Dependency injection via javascript

documentHelper.js

// because you cannot mock window or document we will need to mock these exports
export const getDocument = () => (document);
export const getWindow = () => (window);

index.jsx

import React from 'react';
import { Modal } from 'react-bootstrap';
import { getWindow } from 'LIB/documentHelper';
import textFormatter from './TextFormatter';
export default (props) => (
  <Modal>
    <Modal.Header>
      <Modal.Title>Modal heading</Modal.Title>
    </Modal.Header>
    <Modal.Body>
      <p>{getWindow().isAdmin ? textFormatter('you are an admin') : textFormatter('boiii you lame')}</p>
    </Modal.Body>
    <Modal.Footer>
      <span>Close</span>
    </Modal.Footer>
  </Modal>
);

index.spec.jsx

import { expect, React, Sinon } from 'TEST/TestHelper';
import { shallow } from 'enzyme';

import MuhComponent from './index';
import * as BootStrap from 'react-bootstrap';
import * as documentHelpers from 'LIB/documentHelper';
import * as textFormatter from './TextFormatter';
describe('mocking imports', () => {
  describe('rendering a mock for the bootstrap component', () => {
    let DefaultModal;
    before(() => {
      DefaultModal = BootStrap.Modal;
      BootStrap.Modal = (props) => (
        <div>
          <p id="render_me">this should render</p>
          {props.children}
        </div>
      );
    });

    after(() => {
      BootStrap.Modal = DefaultModal;
    });
    it('should render a mock for bootstraps modal', () => {
      const wrapper = shallow(<MuhComponent />);
      expect(wrapper.dive().find('#render_me').length).to.eq(1);
    });
  })

  describe('not rendering a mock for the bootstrap component', () => {
    it('should render a mock for bootstraps modal', () => {
      const wrapper = shallow(<MuhComponent />);
      expect(wrapper.dive().find('#render_me').length).to.eq(0);
    });
  });
  //
  context('when the user is an admin', () => {
    before(() => {
      Sinon.stub(documentHelpers, 'getWindow', () => ({isAdmin: true}));
    });
  
    after(() => {
      documentHelpers.getWindow.restore();
    });
  
    it('should render the admin text', () => {
      const wrapper = shallow(<MuhComponent />);
      expect(wrapper.find(BootStrap.Modal.Body).dive().text()).to.eq('you are an admin');
    })
  });
  //
  // context('when the user is not an admin', () => {
  //   before(() => {
  //     Sinon.stub(documentHelpers, 'getWindow', () => ({isAdmin: false}));
  //   });
  //
  //   after(() => {
  //     documentHelpers.getWindow.restore();
  //   });
  //
  //   it('should render the admin text', () => {
  //     const wrapper = shallow(<MuhComponent />);
  //     expect(wrapper.find(BootStrap.Modal.Body).dive().text()).to.eq('boiii you lame');
  //   })
  // })
  //
  describe('mocking a default', () => {
    let DefaultFormatter;
    before(() => {
      DefaultFormatter = textFormatter.default;
      textFormatter.default = (text) => text.toUpperCase();
    });
  
    after(() => {
      textFormatter.default = DefaultFormatter;
    });
    it('should mock the formatter', () => {
      const wrapper = shallow(<MuhComponent />);
      expect(wrapper.find(BootStrap.Modal.Body).dive().text()).to.eq('boiii you lame'.toUpperCase());
    })
  })
});

TextFormatter.js

export default (text) => text;