Mocha js Uncaught TypeError：无法读取未定义的属性（读取“应该”）

Question

So I'm trying to test my API and with mocha js and I'm getting this error.

SAMPLE unit test
1) should return posts with tag tech sorted by likes


0 passing (26ms)
1 failing

1) SAMPLE unit test
  should return home page:
  Uncaught TypeError: Cannot read properties of undefined (reading 'should')
  at Test.<anonymous> (test\get_info.test.js:22:18)
  at Test.assert (node_modules\supertest\lib\test.js:172:8)
  at localAssert (node_modules\supertest\lib\test.js:120:14)
  at C:\Users\tiktk\Desktop\Fetch\node_modules\supertest\lib\test.js:125:7
  at Test.Request.callback (node_modules\superagent\lib\node\index.js:927:3)
  at ClientRequest.<anonymous> (node_modules\superagent\lib\node\index.js:844:12)
  at ClientRequest.emit (node:events:390:28)
  at Socket.socketErrorListener (node:_http_client:447:9)
  at Socket.emit (node:events:390:28)
  at emitErrorNT (node:internal/streams/destroy:157:8)
  at emitErrorCloseNT (node:internal/streams/destroy:122:3)
  at processTicksAndRejections (node:internal/process/task_queues:83:21)

I have all the dependencies installed and up to date but I still get that error.

var supertest = require("supertest");
var should = require("should");

var server = supertest.agent("http://127.0.0.1:3000");

describe("Api unit test",function(){

  it("should return posts with tag tech sorted by likes",function(done){

    server
    .get("/api/posts?tags=tech&sortBy=likes&direction=desc")
    .expect("Content-type",/json/)
    .expect(200) 
    .end(function(res){
      // HTTP status should be 200
      res.status.should.equal(200);
      // Error key should be false.
      res.body.error.should.equal(false);
      done();
    });
  });
});

The link should return a bunch of objects in an array as a JSON file sorted by likes (in this case)

Answer 1

The error most probably comes from the fact that res.body.error is undefined when you don't have an error. In which case, your test should be something like:

res.body.should.not.have.property('error')

To confirm my hypothesis, you should console.log the content of res.body before checking for the error.