System.Tests.StringTests.LastIndexOfAny C# (CSharp) Method

        public static void LastIndexOfAny(string s, char[] anyOf, int startIndex, int count, int expected)
        {
            if (count == startIndex + 1)
            {
                if (startIndex == s.Length - 1)
                {
                    Assert.Equal(expected, s.LastIndexOfAny(anyOf));
                }
                Assert.Equal(expected, s.LastIndexOfAny(anyOf, startIndex));
            }
            Assert.Equal(expected, s.LastIndexOfAny(anyOf, startIndex, count));
        }