shallowEqual.js

"use strict";

function shallowEqual(objA, objB, tell) {
  if (objA === objB) {
    return true;
  }

  var keysA = Object.keys(objA);
  var keysB = Object.keys(objB);

  if (keysA.length !== keysB.length) {
    return false;
  }

  // Test for A's keys different from B.
  var hasOwn = Object.prototype.hasOwnProperty;
  for (var i = 0; i < keysA.length; i++) {
    if (!hasOwn.call(objB, keysA[i]) || objA[keysA[i]] !== objB[keysA[i]]) {
      if (tell) {
        return keysA[i];
      }
      return false;
    }
  }

  return true;
}

module.exports = shallowEqual;