public void GroupBy_ArgumentChecking()
{
var ns = default(ISubscribable <int>);
var xs = DummySubscribable <int> .Instance;
var nk = default(Func <int, int>);
var dk = new Func <int, int>(x => x);
var nc = default(IEqualityComparer <int>);
var dc = EqualityComparer <int> .Default;
var ne = default(Func <int, string>);
var de = new Func <int, string>(x => x.ToString());
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(ns, dk));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, nk));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(ns, dk, dc));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, nk, dc));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, dk, nc));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(ns, dk, de));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, nk, de));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, dk, ne));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(ns, dk, de, dc));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, nk, de, dc));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, dk, ne, dc));
ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.GroupBy(xs, dk, de, nc));
}
