node.js - 在带有 supertest 的 Mocha 断言中使用异步等待函数

Question

我正在尝试使用 Mocha 和 Supertest 为我的 Node API 编写测试。

我成功地使用了 .then 的 promise ，但这很快就变成了“回调” hell ，很难长期维持。

// Success using `.then`
describe('/categories', () => {
  it('GET-/categories ,should contain 2 category documents after creating', done => {
    request(app)
      .post('/categories')
      .send({
        name: 'user1',
      })
      .then(res => {
        request(app)
          .post('/categories')
          .send({
            name: 'user2',
          })
          .then(res => {
            request(app)
              .get('/categories')
              .then(res => {
                const categories = res.body;
                expect(categories.length).to.equal(2);
                done();
              });
          });
      })
      .catch(err => done(err));
  });
});

现在我尝试用 async await 编写它，但它返回一个错误。

// DOES NOT WORK using `async`/`await`
describe('/categories', () => {
  it('GET-/categories ,should contain 2 category documents after creating', async done => {
    try {

      const category1 = await request(app)
        .post('/categories')
        .send({
          name: 'user2',
        });

      const category2 = await request(app)
        .post('/categories')
        .send({
          name: 'user2',
        });

      const categories = await request(app).get('/categories');
      const result = categories.body;
      expect(result.length).to.equal(2);
      done();

    } catch (e) {
      done(e);
    }
  });
});

Error: Resolution method is overspecified. Specify a callback or return a Promise; not both.

在研究这个问题时，我看到一些线程建议省略 done()，所以我这样做了，但测试无法正常工作。他们甚至失败的断言也获得通过。

// DOES NOT WORK using `async`/`await` without `done()`
describe('/categories', () => {
  it('GET-/categories ,should contain 2 category documents after creating', async () => {
    try {

      const category1 = await request(app)
        .post('/categories')
        .send({
          name: 'user2',
        });

      const category2 = await request(app)
        .post('/categories')
        .send({
          name: 'user2',
        });

      const categories = await request(app).get('/categories');
      const result = categories.body;
      expect(result.length).to.equal(2);

    } catch (e) {
      console.log(e);
    }
  });
});

Answer 1

好吧，我首先找到答案，你不应该使用 async 传递一个 did() 回调函数，然后使用 try-catch block 语句干扰断言，并且不让测试自然地进行。你可能最好不要将你的断言放在 catch-try 语句中!

it('GET-/categories ,should contain 2 category documents after creating',async()=>{
            const category1 = await  
            request(app).post('/categories')
            .send({
                name       :'user1'
            }); 
            const category2 = await
            request(app).post('/categories')
            .send({
            name       :'user2'
            })

            const result =await 
            request(app).get('/categories')
            .set('Content-Type', 'application/json')
            .set('Acccept', 'application/json')
            .catch(err => { 
                throw err; 
            })
            const categories= result.body;
            expect(categories.length).to.equal(2);

    })