Jest - 如何测试承诺的结果

Question

如何使用 Jest 测试当单元测试中的函数中的承诺得到解决时执行的步骤？

示例：

// FUNCTION TO TEST
export function functionToTest(url) {
  initSomething().then(() => {
    console.log('YEP, CALLED');
    storeHistory.push(url);
  });
}

// UNIT TEST
import { functionToTest, __RewireAPI__ as rewireUtility } from './funcToTest';

describe('functionToTest', () => {
  let pushSpy;
  beforeEach(() => {
    pushSpy = jest.fn();
    rewireUtility.__set__('storeHistory', { push: pushSpy });
    rewireUtility.__set__('initSomething', () => Promise.resolve());
  });

  it('pushes the given url to history after initializing cordova', () => {
    functionToTest('/sports');
    expect(pushSpy).toHaveBeenCalledTimes(1);
    expect(pushSpy).toHaveBeenCalledWith('/sports');
  });
});

在这种情况下，pushSpy 被调用了 0 次（即使打印了日志）。我怎样才能正确测试它？

Answer 1

使用这个解决了：

it.only('pushes the given url to history after initializing cordova', (done) => {
  rewireUtility.__Rewire__('history', { push: (route) => {
        expect(route).toEqual('/sports');
        done();
  } });
  functionToTest('test://sports');
});

Jest - 如何测试承诺的结果

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