What's wrong with my mocha test?

Question

I have written this code in express.js and mongoose

routes.js

var mongoose = require('mongoose'),
    logger = require('../logger');

mongoose.connection.on('error', function(){
    logger.info('Mongoose connection error' + error);
});

exports.getitems = function(req, res) {
    mongoose.connect('mongodb://localhost/abhitest', {auto_reconnect: true, native_parser: true}, function(err){        
        if (err) logger.error("Error " + err);
    });
    var Schema = mongoose.Schema;
    var User = new Schema({
        username : {type: String, required: true},
        email : {type: String, required: true}
    }, {collection: 'User'});

    var UserModel = mongoose.model('User', User, 'User');   
    UserModel.find({}, function(err, users){
        if (!err) {
            logger.info('found ' + users);
            res.json(200, users);
        } else {
            logger.error(err);
            res.json(404, 'did not find anything');
        }
    });
};

app.js

var mongoose = require('mongoose'),
    express = require('express'),
    app = express(),
    routes = require('./routes'),
    http = require('http');

app.get('/', routes.getitems);
http.createServer(app).listen(3000);
module.exports = app;

When I execute this from the browser. I can see that it returns results correctly from my mongo db.

But when I write this mocha test case for the same code

var app = require('../app'),
    request = require('supertest'),
    assert = require('assert'),
    _ = require('underscore');

describe('when the test runs', function() {
    it ('should insert 3 records in mongo db', function(done){
        request(app)
        .get('/')       
        .expect('Content-Type', /json/)
        .expect(200)
        .end(function(err, res){
            if (err) console.log(err);          
            else {
                console.log(res.text);
                var items = JSON.parse(res.text);
                for(var i = 0; i < items.length; i++) {
                    var item = items[i];
                    assert(_.has(item, 'username'));
                    assert(_.has(item, 'email'));
                    console.log(item.username);
                    console.log(item.email);
                }
            }
        });
        done();
    });
});

The test case output is just

․

1 passing (18ms)

So I am very sure that it doesn't even go inside the end method and it doesn't print anything inside the end method.

I can see that the call goes to the server but it never establishes the connection with mongo. it just hangs as readyState of 2.

So somehow when the test is executing via mocha... it never connects to mongo and is hung on connecting. but when the code is executed via npm start... everything works fine.

What is going wrong with mocha test case?

Answer 1

Your done() call needs to be made from within the request callback:

describe('when the test runs', function() {
    it ('should insert 3 records in mongo db', function(done){
        request(app)
        .get('/')       
        .expect('Content-Type', /json/)
        .expect(200)
        .end(function(err, res){
            if (err) console.log(err);          
            else {
                console.log(res.text);
                var items = JSON.parse(res.text);
                for(var i = 0; i < items.length; i++) {
                    var item = items[i];
                    assert(_.has(item, 'username'));
                    assert(_.has(item, 'email'));
                    console.log(item.username);
                    console.log(item.email);
                }
            }
            return done();
        });
    });
});

As it is currently, you call done() before your request is finished.