zoo.js

//------------------------------------------------------------------------------------------------------------------
// YOUR CODE: Create your Zoo "object literal" and Animal "constructor" and "prototypes" here.
//------------------------------------------------------------------------------------------------------------------
function Animal(species, legs){            //object constructor = makes object using keyword
  this.name = species;
  this.numFeet = legs;
 }

Animal.prototype.identify = function(){
  //console.log("I am a" + this.name+ "with" + this.numFeet + "legs.");
  return "I am a " + this.name + " with " + this.numFeet + " legs.";
}

Zoo = { 
  init: function(zooAnimal){
    this.beasties = zooAnimal;
  },

  bipeds: function(){
    return this.findAnimals(2);
  },

  quadrupeds: function(){
    return this.findAnimals(4);
  },

  findAnimals: function(footsies){
    var selectAnimal = [];
    this.beasties.forEach(function(animalObject){
      if(animalObject.numFeet === footsies){
        selectAnimal.push(animalObject)
      }
    });
    return selectAnimal; 
  }
}                                         //object literal = creates an object/ , separates arguments


//------------------------------------------------------------------------------------------------------------------
// DRIVER CODE: Do **NOT** change anything below this point. Your task is to implement code above to make this work.
//------------------------------------------------------------------------------------------------------------------

function assert(test, message) {  
  if (!test) {
    throw "ERROR: " + message;
  }
  return true;
}

var animals = [
  new Animal("Human", 2),
  new Animal("Monkey", 2),
  new Animal("Kangaroo", 2),
  new Animal("Horse", 4),
  new Animal("Cow", 4),
  new Animal("Centipede", 100)
];

Zoo.init(animals);

assert(
  Zoo.bipeds().length === 3, "the Zoo should have 3 bipeds"
);
assert(
  Zoo.quadrupeds().length === 2, "the Zoo should have 2 bipeds"
);
assert(
  animals[0].identify() === "I am a Human with 2 legs.", "humans have 2 legs"
);
assert(
  animals[2].name === "Kangaroo", "expected 'Kangaroo'"
);
assert(
  animals[0].identify === animals[5].identify, "only one implementation of the identify() function should exist"
);