sinon spy as callback not being called

Question

I have my source file for which i have written test cases for

var debug = require('debug')('kc-feed:source:fb');
var request = require('request');
var config = require('../../config').root;


exports.source = function fetchFeed (callback) {
  var params = {
      headers: {'content-type' : 'application/jsons'},
      url: config.host + "v1/social/fb/sync_feed", 
      method: 'GET'
  };

  request(params, function(err, body, response) {
    if(err) {
      callback(err);
    }
    else {
      var raw_data = JSON.parse(response);
      callback(null, raw_data);
    }
  });
};

This is my mocha test case

var chai = require('chai'),
    expect = chai.expect,
    app = require('../app'),
    rewire = require('rewire'),
    fbfeed = rewire('../src/feed/source/fb_feed'),
    supertest = require('supertest'),
    sinon = require('sinon'),
    nock = require('nock');

describe('test cases for fb feed file', function() {
    var callback;
    beforeEach(function(){
        callback = sinon.spy();     
    });

    after(function(){
        nock.cleanAll();
    });

    it('callback should be called with the response', function(done) {
        nock('http://localhost:3000/')
            .get('/v1/social/fb/sync_feed') 
            .reply(200, {});
            callback = sinon.spy();
        fbfeed.source(callback);
        sinon.assert.calledOnce(callback);
        done();
    }); 

    it('callback should be called with the error', function(done) {
        nock('http://localhost:3000/')
            .get('/v1/social/fb/sync_feed') 
            .replyWithError(new Error('err'));
        fbfeed.source(callback);
        sinon.assert.calledOnce(callback);
        done();
    }); 

Both my test cases fail as it says that callback is called 0 times. But the callback is always called. Please help.

Answer 1

It looks like the requests are still being performed asynchronously (I can't definitively say if this is expected when using nock), so you can't use spies like that.

Provide a regular callback instead:

fbfeed.source(function(err, raw_data) {
  ...make your assertions...
  done();
});