Mocha test alway pass

I want to test a Basic Authentication on my webpage with mocha :

describe('Test GET /messages', function(){

    describe('Test HTTP basic authentication', function(){

       it('should return 200 because right credentials', function(done){
           request.get(createCustomRequest(true, "/messages", "test", "test"), function(err, res, body){
               if (err) {
                   console.error(err)
               } else {
                    // Whatever, it will always pass
                    assert.equal(2400, res.statusCode);
               }
           }, done());
        });
  });

function createCustomRequest(withAuth, service, username, password){
    if(!withAuth){
        return {
            url: URL+service,
            followRedirect: false
        };
    } else {
        return {
            url: URL+service,
            followRedirect: false,
            headers: {
                'Authorization': createCredentials(username, password)
            }
        };
    }
}

From the code ahead, I do not understand why the test always pass. I think it is related to the done() callback.

What did I do wrong here?