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

        public static void LastIndexOf_Invalid()
        {
            string s = "foo";

            // Value is null
            Assert.Throws<ArgumentNullException>("value", () => s.LastIndexOf(null));
            Assert.Throws<ArgumentNullException>("value", () => s.LastIndexOf(null, StringComparison.CurrentCulture));
            Assert.Throws<ArgumentNullException>("value", () => s.LastIndexOf(null, 0));
            Assert.Throws<ArgumentNullException>("value", () => s.LastIndexOf(null, 0, 0));
            Assert.Throws<ArgumentNullException>("value", () => s.LastIndexOf(null, 0, 0, StringComparison.CurrentCulture));

            // Start index < 0
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf('a', -1));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf('a', -1, 0));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", -1));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", -1, StringComparison.CurrentCulture));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", -1, 0));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", -1, 0, StringComparison.CurrentCulture));

            // Start index > string.Length
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf('a', s.Length + 1));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf('a', s.Length + 1, 0));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", s.Length + 1));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", s.Length + 1, StringComparison.CurrentCulture));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", s.Length + 1, 0));
            Assert.Throws<ArgumentOutOfRangeException>("startIndex", () => s.LastIndexOf("a", s.Length + 1, 0, StringComparison.CurrentCulture));

            // Count < 0
            Assert.Throws<ArgumentOutOfRangeException>("count", () => s.LastIndexOf('a', 0, -1));
            Assert.Throws<ArgumentOutOfRangeException>("count", () => s.LastIndexOf("a", 0, -1));
            Assert.Throws<ArgumentOutOfRangeException>("count", () => s.LastIndexOf("a", 0, -1, StringComparison.CurrentCulture));

            // Start index - count + 1 < 0
            Assert.Throws<ArgumentOutOfRangeException>("count", () => s.LastIndexOf('a', 0, s.Length + 2));
            Assert.Throws<ArgumentOutOfRangeException>("count", () => s.LastIndexOf("a", 0, s.Length + 2));
            Assert.Throws<ArgumentOutOfRangeException>("count", () => s.LastIndexOf("a", 0, s.Length + 2, StringComparison.CurrentCulture));

            // Invalid comparison type
            Assert.Throws<ArgumentException>("comparisonType", () => s.LastIndexOf("a", StringComparison.CurrentCulture - 1));
            Assert.Throws<ArgumentException>("comparisonType", () => s.LastIndexOf("a", StringComparison.OrdinalIgnoreCase + 1));
            Assert.Throws<ArgumentException>("comparisonType", () => s.LastIndexOf("a", 0, StringComparison.CurrentCulture - 1));
            Assert.Throws<ArgumentException>("comparisonType", () => s.LastIndexOf("a", 0, StringComparison.OrdinalIgnoreCase + 1));
            Assert.Throws<ArgumentException>("comparisonType", () => s.LastIndexOf("a", 0, 0, StringComparison.CurrentCulture - 1));
            Assert.Throws<ArgumentException>("comparisonType", () => s.LastIndexOf("a", 0, 0, StringComparison.OrdinalIgnoreCase + 1));
        }