supertest_chunked_res_ex.js

const express = require('express');
const request = require('supertest');
const chai = require('chai');
const should = chai.should();

const app = express();
app.post('/plain', function(req, res){
  res.set('Transfer-Encoding', 'chunked');  // <- this is the problem
  res.status(200).send('hello');
});

describe('Test plain text response', function() {
  it('should handle 200 response', function (done) {
    request(app)
      .post('/plain')
      .expect(200)
      .end(function (err, res) {
        if (err) return done(err);

        // console.log(res.text);
        res.text.should.equal('hello');
        done();
      });
  });
});