closing of iterators of Set-like objects on early exit

tc39/proposal-set-methods#85

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## Changelog
 ##### Unreleased
+- [`Set` methods proposal](https://github.com/tc39/proposal-set-methods) minor updates:
+  - Closing of iterators of `Set`-like objects on early exit, [proposal-set-methods/85](https://github.com/tc39/proposal-set-methods/pull/85)
 - Added one more workaround of a `webpack` dev server bug on IE global methods, [#1161](https://github.com/zloirock/core-js/issues/1161)
 - Fixed possible `String.{ raw, cooked }` error with empty template array
 - Used non-standard V8 `Error.captureStackTrace` instead of stack parsing in new error classes / wrappers where it's possible

packages/core-js/internals/set-is-disjoint-from.js

@@ -4,7 +4,7 @@ var has = require('../internals/set-helpers').has;
 var size = require('../internals/set-size');
 var getSetRecord = require('../internals/get-set-record');
 var iterateSet = require('../internals/set-iterate');
-var iterateSimple = require('../internals/iterate-simple');
+var iterate = require('../internals/iterate');
 
 // `Set.prototype.isDisjointFrom` method
 // https://tc39.github.io/proposal-set-methods/#Set.prototype.isDisjointFrom
@@ -15,8 +15,8 @@ module.exports = function isDisjointFrom(other) {
     ? iterateSet(O, function (e) {
       if (otherRec.includes(e)) return false;
     }, true)
-    : iterateSimple(otherRec.getIterator(), function (e) {
-      if (has(O, e)) return false;
-    })
+    : !iterate(otherRec.getIterator(), function (e, stop) {
+      if (has(O, e)) return stop();
+    }, { IS_ITERATOR: true, INTERRUPTED: true }).stopped
   );
 };

packages/core-js/internals/set-is-superset-of.js

@@ -3,15 +3,15 @@ var aSet = require('../internals/a-set');
 var has = require('../internals/set-helpers').has;
 var size = require('../internals/set-size');
 var getSetRecord = require('../internals/get-set-record');
-var iterateSimple = require('../internals/iterate-simple');
+var iterate = require('../internals/iterate');
 
 // `Set.prototype.isSupersetOf` method
 // https://tc39.github.io/proposal-set-methods/#Set.prototype.isSupersetOf
 module.exports = function isSupersetOf(other) {
   var O = aSet(this);
   var otherRec = getSetRecord(other);
   if (size(O) < otherRec.size) return false;
-  return iterateSimple(otherRec.getIterator(), function (e) {
-    if (has(O, e) === false) return false;
-  }) !== false;
+  return !iterate(otherRec.getIterator(), function (e, stop) {
+    if (!has(O, e)) return stop();
+  }, { IS_ITERATOR: true, INTERRUPTED: true }).stopped;
 };