public unsafe void AllowNullOnlyNoOp() { fixed(int *value = &_value) { Pointers.AllowNullOnlyNoOp(value); var ex = Assert.ThrowsException <NullReferenceException>(() => Pointers.AllowNullOnlyNoOp(null)); Assert.IsTrue(ex.Message.Contains("output", StringComparison.OrdinalIgnoreCase), "Exception message did not apply to output value."); } }