// Set methods throw when passed a this-value that isn't a Set. load(libdir + "asserts.js"); function testcase(obj, fn, ...args) { assertEq(typeof fn, "function"); assertThrowsInstanceOf(function () { fn.apply(obj, args); }, TypeError); } var Set_size_getter = Object.getOwnPropertyDescriptor(Set.prototype, "size").get; function test(obj) { testcase(obj, Set.prototype.has, 12); testcase(obj, Set.prototype.add, 12); testcase(obj, Set.prototype.delete, 12); testcase(obj, Set.prototype.clear); testcase(obj, Set.prototype.keys); testcase(obj, Set.prototype.values); testcase(obj, Set.prototype.entries); testcase(obj, Set_size_getter); } test(Set.prototype); test(Object.create(new Set)); test(new Map()); test({}); test(null); test(undefined);