Express addition

node_modules/core-js/modules/_object-keys-internal.js

@@ -0,0 +1,17 @@
+var has = require('./_has');
+var toIObject = require('./_to-iobject');
+var arrayIndexOf = require('./_array-includes')(false);
+var IE_PROTO = require('./_shared-key')('IE_PROTO');
+
+module.exports = function (object, names) {
+  var O = toIObject(object);
+  var i = 0;
+  var result = [];
+  var key;
+  for (key in O) if (key != IE_PROTO) has(O, key) && result.push(key);
+  // Don't enum bug & hidden keys
+  while (names.length > i) if (has(O, key = names[i++])) {
+    ~arrayIndexOf(result, key) || result.push(key);
+  }
+  return result;
+};