src/third_party/mozjs-45/js/src/jit-test/tests/collections/WeakSet-constructor-1.js

// The WeakSet constructor creates an empty WeakSet by default.

load(libdir + "asserts.js");

new WeakSet();
new WeakSet(undefined);
new WeakSet(null);

assertThrowsInstanceOf(() => WeakSet(), TypeError);
assertThrowsInstanceOf(() => WeakSet(undefined), TypeError);
assertThrowsInstanceOf(() => WeakSet(null), TypeError);