add a workaround in Object.{ entries, values } for some IE versions…

… bug with invisible integer keys on `null`-prototype objects

CHANGELOG.md

@@ -28,6 +28,7 @@
 - Fixed some cases of increasing buffer size in `ArrayBuffer.prototype.{ transfer, transferToFixedLength }` polyfills
 - Fixed awaiting async `AsyncDisposableStack.prototype.adopt` callback, [#1258](https://github.com/zloirock/core-js/issues/1258)
 - Fixed `URLSearchParams#size` in ES3 engines (IE8-)
+- Added a workaround in `Object.{ entries, values }` for some IE versions bug with invisible integer keys on `null`-prototype objects
 - Added TypeScript definitions to `core-js-compat`, [#1235](https://github.com/zloirock/core-js/issues/1235), thanks [@susnux](https://github.com/susnux)
 - Compat data improvements:
   - [`Set.prototype.difference`](https://github.com/tc39/proposal-set-methods) that was missed in Bun because of [a bug](https://github.com/oven-sh/bun/issues/2309) added in 0.6.0

packages/core-js/internals/object-to-array.js

@@ -1,24 +1,36 @@
 var DESCRIPTORS = require('../internals/descriptors');
+var fails = require('../internals/fails');
 var uncurryThis = require('../internals/function-uncurry-this');
+var objectGetPrototypeOf = require('../internals/object-get-prototype-of');
 var objectKeys = require('../internals/object-keys');
 var toIndexedObject = require('../internals/to-indexed-object');
 var $propertyIsEnumerable = require('../internals/object-property-is-enumerable').f;
 
 var propertyIsEnumerable = uncurryThis($propertyIsEnumerable);
 var push = uncurryThis([].push);
 
+// in some IE versions, `propertyIsEnumerable` returns incorrect result on integer keys
+// of `null` prototype objects
+var IE_BUG = fails(function () {
+  // eslint-disable-next-line es/no-object-create -- safe
+  var O = Object.create(null);
+  O[2] = 2;
+  return !propertyIsEnumerable(O, 2);
+});
+
 // `Object.{ entries, values }` methods implementation
 var createMethod = function (TO_ENTRIES) {
   return function (it) {
     var O = toIndexedObject(it);
     var keys = objectKeys(O);
+    var IE_WORKAROUND = IE_BUG && objectGetPrototypeOf(O) === null;
     var length = keys.length;
     var i = 0;
     var result = [];
     var key;
     while (length > i) {
       key = keys[i++];
-      if (!DESCRIPTORS || propertyIsEnumerable(O, key)) {
+      if (!DESCRIPTORS || (IE_WORKAROUND ? key in O : propertyIsEnumerable(O, key))) {
         push(result, TO_ENTRIES ? [key, O[key]] : O[key]);
       }
     }