src/third_party/mozjs-45/js/src/jit-test/tests/collections/Set-clear-iterators-2.js

// A Set iterator continues to visit entries added after a clear().

load(libdir + "iteration.js");

var s = new Set(["a"]);
var it = s[Symbol.iterator]();
assertIteratorNext(it, "a");
s.clear();
s.add("b");
assertIteratorNext(it, "b");
assertIteratorDone(it, undefined);