function testSingleConstructor(Ctor, test) {
    return function () {
        const methods = Object.getOwnPropertyNames(Intl.platform);
        const cache = {};

        for (const method of methods) {
            cache[method] = Intl.platform[method];
        }

        test(Ctor);

        for (const method of methods) {
            Intl.platform[method] = cache[method];
        }
    }
}
Caches all methods on Intl.platform and restores them after the test executes