import addMissingHistoryEvents from './history-events';


it("should overwrite pushstate and replacestate with event-emitting functions", () => {
  // given
  const pushState = jest.fn();
  const replaceState = jest.fn();
  const window = {
    dispatchEvent: jest.fn(),
    history: {
      pushState,
      replaceState
    }
  };

  // when
  addMissingHistoryEvents(window, window.history);
  window.history.pushState({item: 'push'},'pushstate', '/pushstate');
  window.history.replaceState({item: 'replace'},'replacestate', '/replacestate');

  //then
  expect(pushState.mock.calls).toEqual([[{item:'push'}, 'pushstate', '/pushstate']]);
  expect(replaceState.mock.calls).toEqual([[{item: 'replace'},'replacestate', '/replacestate']]);
  expect(window.dispatchEvent.mock.calls.length).toEqual(2);
  const windowCalls = window.dispatchEvent.mock.calls;

  expect(windowCalls[0][0].detail).toEqual({state: {item:'push'}, title: 'pushstate', url: '/pushstate'});
  expect(windowCalls[1][0].detail).toEqual({state: {item:'replace'}, title: 'replacestate', url: '/replacestate'});

});

it("should only add history-events once if called any number of times on same objects", () => {
  // given
  const pushState = jest.fn();
  const replaceState = jest.fn();
  const window = {
    dispatchEvent: jest.fn(),
    history: {
      pushState,
      replaceState
    }
  };

  // when
  addMissingHistoryEvents(window, window.history);
  addMissingHistoryEvents(window, window.history);
  addMissingHistoryEvents(window, window.history);
  addMissingHistoryEvents(window, window.history);

  window.history.pushState({item: 'push'},'pushstate', '/pushstate');
  window.history.replaceState({item: 'replace'},'replacestate', '/replacestate');

  //then
  expect(window.dispatchEvent.mock.calls.length).toEqual(2);

});