node_modules/jszip/node_modules/core-js/modules/_enum-keys.js

// all enumerable object keys, includes symbols
var getKeys = require('./_object-keys')
  , gOPS    = require('./_object-gops')
  , pIE     = require('./_object-pie');
module.exports = function(it){
  var result     = getKeys(it)
    , getSymbols = gOPS.f;
  if(getSymbols){
    var symbols = getSymbols(it)
      , isEnum  = pIE.f
      , i       = 0
      , key;
    while(symbols.length > i)if(isEnum.call(it, key = symbols[i++]))result.push(key);
  } return result;
};