add a workaround for V8 Array#{ splice, filter, map } deoptimizatio…

…n which causes 100x+ performance degradation of those methods, close #624
zloirock · Oct 24, 2019 · 9720739 · 9720739
1 parent 34a8a4d
commit 9720739
Show file tree

Hide file tree

Showing 2 changed files with 4 additions and 3 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## Changelog
 ##### Unreleased
+- Added a workaround for V8 `Array#{ splice, filter, map }` deoptimization which causes 100x+ performance degradation of those methods, [#624](https://github.com/zloirock/core-js/issues/624)
 - Fixed work of `fetch` with polyfilled `URLSearchParams`, [#674](https://github.com/zloirock/core-js/issues/674)
 - `package-lock.json` no longer generated in libraries
 

diff --git a/packages/core-js/internals/array-method-has-species-support.js b/packages/core-js/internals/array-method-has-species-support.js
@@ -5,11 +5,11 @@ var SPECIES = wellKnownSymbol('species');
 
 module.exports = function (METHOD_NAME) {
   return !fails(function () {
-    var array = [];
-    var constructor = array.constructor = {};
+    var object = {};
+    var constructor = object.constructor = {};
     constructor[SPECIES] = function () {
       return { foo: 1 };
     };
-    return array[METHOD_NAME](Boolean).foo !== 1;
+    return [][METHOD_NAME].call(object, Boolean).foo !== 1;
   });
 };