isPalindrome-test.js

var expect = require('chai').expect;
var isPalindrome = require('../src/ispalindrome');

describe('palindrome-test', function() {
  it('should pass this canary test', function() {
    expect(true).to.be.true;
  });

  it('should return true for argument mom', function() {
    expect(isPalindrome('mom')).to.be.true;
  });
  
  it('should return true for argument dad', function() {
    expect(isPalindrome('dad')).to.be.true;
  });
  
  it('should return false for argument dude', function() {
    expect(isPalindrome('dude')).to.be.false;
  });
  
  it ('should throw an exception when argument is missing', function() {
	  var call = function() { isPalindrome() }
	  expect(call).to.throw(Error, 'Invalid Argument');
  });
  
  it('should return true for argument mom mom', function() {
    expect(isPalindrome('mom mom')).to.be.true;
  });
  
  it('should return false for argument mom dad', function() {
    expect(isPalindrome('mom dad')).to.be.false;
  });
});

isPalindrome.js

module.exports = function(phrase) {
	if (phrase === undefined) {
		throw new Error('Invalid Argument');
	}
	return phrase.trim().length > 0 && 
		phrase.split('').reverse().join('') === phrase;
}

package.json

{
  "name": "palindrome",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "directories": {
    "test": "test"
  },
  "scripts": {
    "test": "mocha test",
    "node": "node_modules/istanbul/lib/cli.js cover node_modules/mocha/bin/_mocha"
  },
  "author": "Greg Helton",
  "license": "ISC",
  "devDependencies": {
    "chai": "^3.5.0",
    "istanbul": "^0.4.2",
    "mocha": "^2.4.5"
  }
}