public async Task When_function_of_task_int_in_async_method_throws_not_excepted_exception_it_should_succeed()
        {
            // Arrange
            var asyncObject      = new AsyncClass();
            Func <Task <int> > f = () => asyncObject.ThrowTaskIntAsync <InvalidOperationException>(true);

            // Act / Assert
            await f.Should().NotThrowAsync <ArgumentNullException>();
        }
        public void When_function_of_task_int_in_async_method_throws_the_expected_exception_it_should_succeed()
        {
            // Arrange
            var asyncObject      = new AsyncClass();
            Func <Task <int> > f = () => asyncObject.ThrowTaskIntAsync <ArgumentNullException>(true);

            // Act / Assert
            f.Should().Throw <ArgumentNullException>();
        }