Add tests for CopyToExtensions

tests/Jellyfin.Common.Tests/Extensions/CopyToExtensionsTests.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Collections.Generic;
+using MediaBrowser.Common.Extensions;
+using Xunit;
+
+namespace Jellyfin.Common.Tests.Extensions
+{
+    public static class CopyToExtensionsTests
+    {
+        public static IEnumerable<object[]> CopyTo_Valid_Correct_TestData()
+        {
+            yield return new object[] { new[] { 0, 1, 2, 3, 4, 5 }, new[] { 0, 0, 0, 0, 0, 0 }, 0, new[] { 0, 1, 2, 3, 4, 5 } };
+            yield return new object[] { new[] { 0, 1, 2 }, new[] { 5, 4, 3, 2, 1, 0 }, 2, new[] { 5, 4, 0, 1, 2, 0 } };
+        }
+
+        [Theory]
+        [MemberData(nameof(CopyTo_Valid_Correct_TestData))]
+        public static void CopyTo_Valid_Correct<T>(IReadOnlyList<T> source, IList<T> destination, int index, IList<T> expected)
+        {
+            source.CopyTo(destination, index);
+            Assert.Equal(expected, destination);
+        }
+
+        public static IEnumerable<object[]> CopyTo_Invalid_ThrowsArgumentOutOfRangeException_TestData()
+        {
+            yield return new object[] { new[] { 0, 1, 2, 3, 4, 5 }, new[] { 0, 0, 0, 0, 0, 0 }, -1 };
+            yield return new object[] { new[] { 0, 1, 2 }, new[] { 5, 4, 3, 2, 1, 0 }, 6 };
+            yield return new object[] { new[] { 0, 1, 2 }, Array.Empty<int>(), 0 };
+            yield return new object[] { new[] { 0, 1, 2, 3, 4, 5 }, new[] { 0 }, 0 };
+            yield return new object[] { new[] { 0, 1, 2, 3, 4, 5 }, new[] { 0, 0, 0, 0, 0, 0 }, 1 };
+        }
+
+        [Theory]
+        [MemberData(nameof(CopyTo_Invalid_ThrowsArgumentOutOfRangeException_TestData))]
+        public static void CopyTo_Invalid_ThrowsArgumentOutOfRangeException<T>(IReadOnlyList<T> source, IList<T> destination, int index)
+        {
+            Assert.Throws<ArgumentOutOfRangeException>(() => source.CopyTo(destination, index));
+        }
+    }
+}