Javascript 在jest模拟中指定函数参数

我目前正在编写单元测试来提高我的覆盖率，我被困在一个函数上，我想设置一个函数的输入参数

我想测试的功能是：

this.map.forEachFeatureAtPixel(e.pixel, (event: any) => {
    if (
      event.values_.name === 'name'
    ) {
      this.openWeatherData(event.values_.name);
    } //more logic ...
  });

我想测试回调函数中的代码，以测试是否进行了正确的调用

但是如何将事件参数设置为

{ values_ : { name: 'name' } }

并执行实际回调实现以提高覆盖率。

用于为

此.map.forEachFeatureAtPixel（）方法及其模拟实现创建模拟版本。模拟实现接受两个参数：
pixel
和
callback
。使用模拟事件对象手动调用
回调
函数

例如

index.ts
：

export const obj = {
  map: {
    // simulate real implementation
    forEachFeatureAtPixel(pixel, callback) {
      callback();
    },
  },
  method(e) {
    this.map.forEachFeatureAtPixel(e.pixel, (event: any) => {
      if (event.values_.name === 'name') {
        console.log('openWeatherData');
      }
    });
  },
};

import { obj } from './';

describe('67818053', () => {
  it('should pass', () => {
    const mEvent = { values_: { name: 'name' } };
    const forEachFeatureAtPixelSpy = jest
      .spyOn(obj.map, 'forEachFeatureAtPixel')
      .mockImplementationOnce((pixel, callback) => {
        callback(mEvent);
      });
    obj.method({ pixel: '12' });
    expect(forEachFeatureAtPixelSpy).toBeCalledWith('12', expect.any(Function));
    forEachFeatureAtPixelSpy.mockRestore();
  });
});

index.test.ts
：

export const obj = {
  map: {
    // simulate real implementation
    forEachFeatureAtPixel(pixel, callback) {
      callback();
    },
  },
  method(e) {
    this.map.forEachFeatureAtPixel(e.pixel, (event: any) => {
      if (event.values_.name === 'name') {
        console.log('openWeatherData');
      }
    });
  },
};

import { obj } from './';

describe('67818053', () => {
  it('should pass', () => {
    const mEvent = { values_: { name: 'name' } };
    const forEachFeatureAtPixelSpy = jest
      .spyOn(obj.map, 'forEachFeatureAtPixel')
      .mockImplementationOnce((pixel, callback) => {
        callback(mEvent);
      });
    obj.method({ pixel: '12' });
    expect(forEachFeatureAtPixelSpy).toBeCalledWith('12', expect.any(Function));
    forEachFeatureAtPixelSpy.mockRestore();
  });
});

测试结果：

 PASS  examples/67818053/index.test.ts (8.297 s)
  67818053
    ✓ should pass (14 ms)

  console.log
    openWeatherData

      at examples/67818053/index.ts:11:17

Test Suites: 1 passed, 1 total
Tests:       1 passed, 1 total
Snapshots:   0 total
Time:        9.055 s