coerce negative set size in get-set-record to 0

Author: zloirock

CHANGELOG.md

@@ -1,7 +1,8 @@
 ## Changelog
 ##### Unreleased
-- [`Set` methods proposal](https://github.com/tc39/proposal-set-methods) minor updates:
+- [`Set` methods proposal](https://github.com/tc39/proposal-set-methods) updates:
   - Closing of iterators of `Set`-like objects on early exit, [proposal-set-methods/85](https://github.com/tc39/proposal-set-methods/pull/85)
+  - Some other minor internal changes
 - 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/get-set-record.js

@@ -4,6 +4,7 @@ var call = require('../internals/function-call');
 var toIntegerOrInfinity = require('../internals/to-integer-or-infinity');
 
 var $TypeError = TypeError;
+var max = Math.max;
 
 var SetRecord = function (set, size, has, keys) {
   this.set = set;
@@ -31,7 +32,7 @@ module.exports = function (obj) {
   if (numSize != numSize) throw $TypeError('Invalid size');
   return new SetRecord(
     obj,
-    toIntegerOrInfinity(numSize),
+    max(toIntegerOrInfinity(numSize), 0),
     aCallable(obj.has),
     aCallable(obj.keys)
   );