gistfile1.cs

        [TestMethod]
        public void AssertNestedInnerException()
        {
            var expectedExcpetion = new Exception();

            new Action(
                () =>
                {
                    throw new InvalidOperationException("", new KeyNotFoundException("", expectedExcpetion));
                })
                .ShouldThrow<InvalidOperationException>()
                .WithInnerException<KeyNotFoundException>()
                .Which.InnerException.InnerException.Should().Be(expectedExcpetion);
        }