remove sort from Set.prototype.intersection

babel/proposals#87 (comment)
tc39/proposal-set-methods#94

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## Changelog
 ##### Unreleased
+- [`Set` methods proposal](https://github.com/tc39/proposal-set-methods):
+  - Removed sort from `Set.prototype.intersection`, [March 2023 TC39 meeting](https://github.com/babel/proposals/issues/87#issuecomment-1478610425), [proposal-set-methods/94](https://github.com/tc39/proposal-set-methods/pull/94)
 - [`Iterator.range` proposal](https://github.com/tc39/proposal-Number.range) moved to Stage 2, [March 2023 TC39 meeting](https://github.com/babel/proposals/issues/87#issuecomment-1480266760)
 - (Async) Explicit Resource Management proposals:
   - `(Async)DisposableStack.prototype.move` marks the original stack as disposed, [#1226](https://github.com/zloirock/core-js/issues/1226)

packages/core-js-pure/override/internals/set-helpers.js

@@ -9,7 +9,5 @@ module.exports = {
   add: caller('add', 1),
   has: caller('has', 1),
   remove: caller('delete', 1),
-  proto: SetPrototype,
-  $has: SetPrototype.has,
-  $keys: SetPrototype.keys
+  proto: SetPrototype
 };

packages/core-js/internals/set-helpers.js

@@ -9,7 +9,5 @@ module.exports = {
   add: uncurryThis(SetPrototype.add),
   has: uncurryThis(SetPrototype.has),
   remove: uncurryThis(SetPrototype['delete']),
-  proto: SetPrototype,
-  $has: SetPrototype.has,
-  $keys: SetPrototype.keys
+  proto: SetPrototype
 };

packages/core-js/internals/set-intersection.js

@@ -9,12 +9,6 @@ var iterateSimple = require('../internals/iterate-simple');
 var Set = SetHelpers.Set;
 var add = SetHelpers.add;
 var has = SetHelpers.has;
-var nativeHas = SetHelpers.$has;
-var nativeKeys = SetHelpers.$keys;
-
-var isNativeSetRecord = function (record) {
-  return record.has === nativeHas && record.keys === nativeKeys;
-};
 
 // `Set.prototype.intersection` method
 // https://github.com/tc39/proposal-set-methods
@@ -23,19 +17,10 @@ module.exports = function intersection(other) {
   var otherRec = getSetRecord(other);
   var result = new Set();
 
-  // observable side effects
-  if (!isNativeSetRecord(otherRec) && size(O) > otherRec.size) {
+  if (size(O) > otherRec.size) {
     iterateSimple(otherRec.getIterator(), function (e) {
       if (has(O, e)) add(result, e);
     });
-
-    if (size(result) < 2) return result;
-
-    var disordered = result;
-    result = new Set();
-    iterateSet(O, function (e) {
-      if (has(disordered, e)) add(result, e);
-    });
   } else {
     iterateSet(O, function (e) {
       if (otherRec.includes(e)) add(result, e);

packages/core-js/modules/esnext.set.intersection.v2.js

@@ -1,9 +1,15 @@
 var $ = require('../internals/export');
+var fails = require('../internals/fails');
 var intersection = require('../internals/set-intersection');
 var setMethodAcceptSetLike = require('../internals/set-method-accept-set-like');
 
+var INCORRECT = !setMethodAcceptSetLike('intersection') || fails(function () {
+  // eslint-disable-next-line es/no-array-from, es/no-set -- testing
+  return Array.from(new Set([1, 2, 3]).intersection(new Set([3, 2]))) != '3,2';
+});
+
 // `Set.prototype.intersection` method
 // https://github.com/tc39/proposal-set-methods
-$({ target: 'Set', proto: true, real: true, forced: !setMethodAcceptSetLike('intersection') }, {
+$({ target: 'Set', proto: true, real: true, forced: INCORRECT }, {
   intersection: intersection
 });

tests/compat/tests.js

@@ -1714,7 +1714,7 @@ GLOBAL.tests = {
     return Set.from;
   },
   'esnext.set.intersection.v2': function () {
-    return Set.prototype.intersection;
+    return Array.from(new Set([1, 2, 3]).intersection(new Set([3, 2]))) == '3,2';
   },
   'esnext.set.is-disjoint-from.v2': function () {
     return Set.prototype.isDisjointFrom;

tests/unit-global/esnext.set.intersection.js

@@ -18,10 +18,10 @@ QUnit.test('Set#intersection', assert => {
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([4, 5]))), []);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([2, 3, 4]))), [2, 3]);
 
-  assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2]))), [2, 3]);
+  assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2]))), [3, 2]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2, 1]))), [1, 2, 3]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2, 1, 0]))), [1, 2, 3]);
-  assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2]))), [2, 3]);
+  assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2]))), [3, 2]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2, 1]))), [1, 2, 3]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2, 1, 0]))), [1, 2, 3]);
 

tests/unit-pure/esnext.set.intersection.js

@@ -19,10 +19,10 @@ QUnit.test('Set#intersection', assert => {
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([4, 5]))), []);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([2, 3, 4]))), [2, 3]);
 
-  assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2]))), [2, 3]);
+  assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2]))), [3, 2]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2, 1]))), [1, 2, 3]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(new Set([3, 2, 1, 0]))), [1, 2, 3]);
-  assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2]))), [2, 3]);
+  assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2]))), [3, 2]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2, 1]))), [1, 2, 3]);
   assert.deepEqual(from(new Set([1, 2, 3]).intersection(createSetLike([3, 2, 1, 0]))), [1, 2, 3]);