objectEquivalence.js

// Warm up 6/18/2019
// Week01 Day 3
// Object Equality?

// In JS, two different objects are never actually equal
// const objA = {a: 7, b: 8}
// const objB = {a: 7, b: 8}
// objA === objB -> false
// objA == objB -> false

// that is... unless they reference the same data
// var objC = objA
// objA === objC -> true
// objA == objC -> true

// Write a function that takes two objects and returns true if
// both objects have the same exact key/value pairs. You can
// assume all values are primitive data types (no arrays, objects, etc)

const isEquivalentObject = function(objA, objB) {
  var keys1 = Object.keys(objA).sort();
  var keys2 = Object.keys(objB).sort();
  if (keys1.length !== keys2.length) {
    return false;
  }

  // ensure key are identical
  for (let i = 0; i < keys1.length; i++) {
    if (keys1[i] !== keys2[i]) {
      return false;
    }
  }

  // sure entries are identical
  return keys1.every(function(key) {
    return objA[key] === objB[key];
  });
};

// Create 5 test cases on your own. Here are a few to start you off!
console.log(isEquivalentObject({ a: 7 }, { a: 7 }) === true); // true
console.log(isEquivalentObject({ a: 7 }, { a: 7, b: 8 }) === false); // false
console.log(isEquivalentObject({ a: "cat" }, { a: "cat" }) === true); // huh.. should this be true or false?🤔
console.log(
  isEquivalentObject({ a: "cat", b: "bone" }, { b: "bone", a: "cat" }) === true
);
console.log(isEquivalentObject({ a: undefined }, { b: undefined }) === false);