function addModuleSuite ({ fetch, Request, Response, Headers }) {
  it('should have the fetch function exposed', () => {
    expect(fetch).to.be.a('function')
  })

  it('should have the Request constructor exposed', () => {
    expect(Request).to.be.a('function')
  })

  it('should have the Response constructor exposed', () => {
    expect(Response).to.be.a('function')
  })

  it('should have Headers constructor exposed', () => {
    expect(Headers).to.be.a('function')
  })
}
This file has all the tests needed to ensure cross-fetch is properly and equally
imported/required in webpack bundle for node and browser environments.