ExtensionsLastIndexOfTest

using System.Linq;
using Xunit;
using Xunit.Abstractions;

namespace AlgorithmForce.Searching.Test
{
    public class ExtensionsLastIndexOfTest : ExtensionsTest
    {
        public ExtensionsLastIndexOfTest(ITestOutputHelper output)
            : base(output)
        {
        }

        [Fact]
        public override void TestCaseList()
        {
            var s = Enumerable.Range(0, 100).ToList();
            var t = new[] { 5, 6, 7, 8, 9 };

            Assert.Equal(5, s.LastIndexOf(t));
        }

        [Fact]
        public override void TestCaseListWithStartIndex()
        {
            var s = Enumerable.Range(0, 100).ToList();
            var t = new[] { 10, 11, 12, 13, 14 };

            Assert.Equal(10, s.LastIndexOf(t, 15));
        }

        [Fact]
        public override void TestCaseListNotFound()
        {
            var s = Enumerable.Range(0, 100).ToList();
            var t = new[] { 8, 10, 12, 12, 14 };

            Assert.Equal(-1, s.LastIndexOf(t));
        }

        [Fact]
        public override void TestCaseListWithStartIndexNotFound()
        {
            var s = Enumerable.Range(0, 100).ToList();
            var t = new[] { 15, 16, 17, 18, 19 };

            Assert.Equal(-1, s.LastIndexOf(t, 17));
        }

        [Fact]
        public override void TestCaseSingleElement()
        {
            var s = @"Vr";
            var t = new[] { 'r' };

            Assert.Equal(1, s.LastIndexOf(t));
        }

        /// <summary>
        /// In this test case, we are going to compare
        /// string.LastIndexOf() and Extensions.LastIndexOf() to see
        /// if they have same behavior.
        /// </summary>
        [Fact]
        public override void TestCaseString()
        {
            var s = string.Concat("Vrogros, the Underlord, is a melee strength hero ",
                "whose commanding presence is crucial to his team's success. ",
                "With his long-lasting abilities, Underlord is able to ",
                "control wide areas of the battlefield during teamfights.");
            var t = new[] { 'V', 'r', 'o', 'g', 'r', 'o', 's' };

            Assert.Equal(s.LastIndexOf(string.Concat(t)), s.LastIndexOf(t));
        }

        /// <summary>
        /// In this test case, we are going to compare
        /// string.LastIndexOf() and Extensions.LastIndexOf() to see
        /// if they have same behavior.
        /// </summary>
        [Fact]
        public override void TestCaseStringWithStartIndex()
        {
            var s = string.Concat("Vrogros, the Underlord, is a melee strength hero ",
                "whose commanding presence is crucial to his team's success. ",
                "With his long-lasting abilities, Underlord is able to ",
                "control wide areas of the battlefield during teamfights.");
            var t = new[] { 'U', 'n', 'd', 'e', 'r', 'l', 'o', 'r', 'd' };

            Assert.Equal(s.LastIndexOf(string.Concat(t), 128), s.LastIndexOf(t, 128));
        }

        [Fact]
        public override void TestCaseStringNotFound()
        {
            var s = @"Vrogros, the Underlord, is a melee strength hero
                whose commanding presence is crucial to his team's success.
                With his long-lasting abilities, Underlord is able to
                control wide areas of the battlefield during teamfights.";
            var t = new[] { 'S', 'u', 'n', ' ', 'W', 'u', 'k', 'o', 'n', 'g' };

            Assert.Equal(-1, s.LastIndexOf(t));
        }

        [Fact]
        public override void TestCaseStringWithStartIndexNotFound()
        {
            var s = string.Concat("Vrogros, the Underlord, is a melee strength hero ",
                "whose commanding presence is crucial to his team's success. ",
                "With his long-lasting abilities, Underlord is able to ",
                "control wide areas of the battlefield during teamfights.");
            var t = new[] { 't', 'e', 'a', 'm', 'f', 'i', 'g', 'h', 't', 's' };

            Assert.Equal(-1, s.LastIndexOf(t, 128));
        }
    }
}