public void Contains_ArgumentChecking() { #pragma warning disable IDE0034 // Simplify 'default' expression (illustrative of method signature) ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.Contains <int>(default(ISubscribable <int>), 0)); ReactiveAssert.Throws <ArgumentNullException>(() => Subscribable.Contains <int>(DummySubscribable <int> .Instance, 0, null)); #pragma warning restore IDE0034 // Simplify 'default' expression }