笑話：如何模擬功能並測試其功能？

Question

我有一個遍歷數組並為每個元素發出HTTP請求的方法：

文件處理器.js

const chunkFile = (array) => {
  return array.map(el => {
    sendChunkToNode(el);
  });
};

const sendChunkToNode = (data) =>
  new Promise((resolve, reject) => {
    request.post(...);
  });

export default {
  chunkFile,
  sendChunkToNode,
};

我已經有一個sendChunkToNode測試：

describe("sendChunkToNode", () => {
  beforeEach(() => {
    // TODO: figure out how to mock request with certain params
    nock(API.HOST)
      .post(API.V1_UPLOAD_CHUNKS_PATH)
      .reply(201, {
        ok: true
      });
  });

  it("makes a POST request to /api/v1/upload-chunks", async () => {
    const response = await FileProcessor.sendChunkToNode(
      1,
      "not_encrypted",
      "handle"
    );
    expect(response).toEqual({ ok: true });
  });
});

我現在要測試chunkFile。 在測試中，我只想測試sendChunkToNode是用不同的元素調用的。 像這樣：

describe("chunkFile", () => {
  it("calls sendChunkToNode with each element", async () => {
    expect(sendChunkToNode).toBeCalledWith(1) //<--- I made the toBeCalledWith method up
    expect(sendChunkToNode).toBeCalledWith(2) //<--- I made the toBeCalledWith method up
    chunkFile([1,2]);
  });
});

Jest有辦法做到這一點嗎？

Answer 1

按照編寫方式，您應該進行循環並執行nock次數與數組中元素的數量一樣多。 然后，您調用chunkFile() ; 如果有未決的Nock請求，則表示出了點問題，測試將失敗。

test('...', () => {

  const someArray = ['a', 'b', 'c']; // someArray.length == 3
  someArray.forEach(element => {
    nock(...); // set up nock using element value
  });

  // if the nock interceptors you set up don't match any request, it will throw an error
  chunkFile(someArray); 
});