fix detection of @@species support in Promise in some old engines

zloirock · Jul 25, 2022 · ae23b5a · ae23b5a
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,6 +1,6 @@
 ## Changelog
 ##### Unreleased
-- Nothing
+- Fixed detection of `@@species` support in `Promise` in some old engines
 
 ##### [3.24.0 - 2022.07.25](https://github.com/zloirock/core-js/releases/tag/v3.24.0)
 - Recent updates of the [iterator helpers proposal](https://github.com/tc39/proposal-iterator-helpers), [#1101](https://github.com/zloirock/core-js/issues/1101):

diff --git a/packages/core-js/internals/promise-constructor-detection.js b/packages/core-js/internals/promise-constructor-detection.js
@@ -26,7 +26,7 @@ var FORCED_PROMISE_CONSTRUCTOR = isForced('Promise', function () {
   // We can't use @@species feature detection in V8 since it causes
   // deoptimization and performance degradation
   // https://github.com/zloirock/core-js/issues/679
-  if (V8_VERSION < 51 || !/native code/.test(PROMISE_CONSTRUCTOR_SOURCE)) {
+  if (!V8_VERSION || V8_VERSION < 51 || !/native code/.test(PROMISE_CONSTRUCTOR_SOURCE)) {
     // Detect correctness of subclassing with @@species support
     var promise = new NativePromiseConstructor(function (resolve) { resolve(1); });
     var FakePromise = function (exec) {