类型错误：无法使用 JEST 单元测试读取 NodeJS 中未定义的属性“应用”

Question

I am new to jest unit testing as well as NodeJS and i'm trying to test my API using the following code.

const request = require('supertest');
const quick_registration = require('../../../routes/register/quick_registration_of_user')

describe('Quick Registration of users', () => {
    beforeAll(() => {
        con.connect();
    });

    describe("GET / ", () => {
        test("It should respond with an array of students", async () => {
          const response = await request(quick_registration).get("/api/quickregistration");
          expect(response.status).toBe(200);
        });
      });
})

But the test keep failing and throws me an error

 FAIL  tests/routes/register/quick_registration_of_user.test.js
  Quick Registration of users
    GET /
      × It should respond with an array of students (20ms)

  ● Quick Registration of users › GET /  › It should respond with an array of students

    TypeError: Cannot read property 'apply' of undefined

      at node_modules/express/lib/router/index.js:635:15
      at next (node_modules/express/lib/router/index.js:260:14)
      at Function.handle (node_modules/express/lib/router/index.js:174:3)
      at Server.router (node_modules/express/lib/router/index.js:47:12)

Test Suites: 1 failed, 1 total
Tests:       1 failed, 1 total
Snapshots:   0 total
Time:        1.649s, estimated 2s
Ran all test suites.
Jest did not exit one second after the test run has completed.

This usually means that there are asynchronous operations that weren't stopped in your tests. Consider running Jest with `--detectOpenHandles` to troubleshoot this issue.

Answer 1

I'm assuming the line

const quick_registration = require('../../../routes/register/quick_registration_of_user')

is requiring the file where you've defined your router. You need to be requiring instead the file where you define your app.