core-js/modules/$.assign.js

Standard library

// 19.1.2.1 Object.assign(target, source, ...)
var toObject = require('./$.to-object')
  , IObject  = require('./$.iobject')
  , enumKeys = require('./$.enum-keys');

module.exports = require('./$.fails')(function(){
  return Symbol() in Object.assign({}); // Object.assign available and Symbol is native
}) ? function assign(target, source){   // eslint-disable-line no-unused-vars
  var T = toObject(target)
    , l = arguments.length
    , i = 1;
  while(l > i){
    var S      = IObject(arguments[i++])
      , keys   = enumKeys(S)
      , length = keys.length
      , j      = 0
      , key;
    while(length > j)T[key = keys[j++]] = S[key];
  }
  return T;
} : Object.assign;