card.js

exports.Card = function(suit,rank) {
	
	function constructor() {}; 
	constructor.prototype.getSuit = function() {
		return suit; } ;
	constructor.prototype.getRank = function() {
		return rank; } ;
  

  	return new constructor(); 

}

card_spec.js

var expect = require('chai').expect,
Card = require('../lib/card').Card;

describe('Card object tests', function(){
	'use strict';
  var card;

  beforeEach(function(){
    card = new Card('Hearts','8');

    card.suit = 'spades';
    card.rank = '4';
  });

  describe('constructor', function() {
    it('card should be truthy (exists)', function(){
      expect(card).to.be.ok;
    });
    it('card should have correct suit', function() {
      expect(card.getSuit()).to.equal('Hearts');
    });
    it('card should have correct rank', function() {
      expect(card.getRank()).to.equal('8');
    });

  });
});