describe('getEventSources', () => {
  pushOptions({
    now: '2015-08-07',
    initialView: 'timeGridWeek',
    eventSources: [
      {
        events: [
          { id: '1', start: '2015-08-07T02:00:00', end: '2015-08-07T03:00:00', title: 'event A' },
        ],
      },
      {
        events: [
          { id: '2', start: '2015-08-07T03:00:00', end: '2015-08-07T04:00:00', title: 'event B' },
        ],
      },
      {
        events: [
          { id: '3', start: '2015-08-07T04:00:00', end: '2015-08-07T05:00:00', title: 'event C' },
        ],
      },
    ],
  })

  it('does not mutate when removeEventSource is called', (done) => {
    initCalendar()
    let eventSources = currentCalendar.getEventSources()
    expect(eventSources.length).toBe(3)

    // prove that eventSources is a copy, and wasn't mutated
    eventSources[0].remove()
    expect(eventSources.length).toBe(3)

    done()
  })
})