Added an IList extensions class that can sort IList<T> using the insertion sort algorithm

git-svn-id: file:///srv/devel/repo-conversion/nusu@337 d2e56fa2-650e-0410-a79f-9358c0239efd

Nuclex.Support (net-4.0).csproj

@@ -105,6 +105,8 @@
     <Compile Include="Source\Collections\Deque.Test.cs">
       <DependentUpon>Deque.cs</DependentUpon>
     </Compile>
+    <Compile Include="Source\Collections\IListExtensions.cs" />
+    <Compile Include="Source\Collections\IListExtensions.Test.cs" />
     <Compile Include="Source\Collections\IMultiDictionary.cs" />
     <Compile Include="Source\Collections\IObservableCollection.cs" />
     <Compile Include="Source\Collections\IRecyclable.cs" />

Source/Collections/IListExtensions.Test.cs

@@ -0,0 +1,67 @@
+#region CPL License
+/*
+Nuclex Framework
+Copyright (C) 2002-2017 Nuclex Development Labs
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the IBM Common Public License as
+published by the IBM Corporation; either version 1.0 of the
+License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+IBM Common Public License for more details.
+
+You should have received a copy of the IBM Common Public
+License along with this library
+*/
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+#if UNITTEST
+
+using NUnit.Framework;
+
+namespace Nuclex.Support.Collections {
+
+  /// <summary>Unit Test for the IList extension methods</summary>
+  [TestFixture]
+  internal class IListExtensionsTest {
+
+    /// <summary>Tests whether the insertion sort algorithm can be applied to 'Text' property works as expected</summary>
+    [Test]
+    public void InsertionSortCanSortWholeList() {
+      var testList = new List<int>(capacity: 5) { 1, 5, 2, 4, 3 };
+      var testListAsIList = (IList<int>)testList;
+      
+      testListAsIList.InsertionSort();
+
+      CollectionAssert.AreEqual(
+        new List<int>(capacity: 5) { 1, 2, 3, 4, 5 },
+        testList
+      );
+    }
+
+    /// <summary>Tests whether the 'Text' property works as expected</summary>
+    [Test]
+    public void InsertionSortCanSortListSegment() {
+      var testList = new List<int>(capacity: 7) { 9, 1, 5, 2, 4, 3, 0 };
+      var testListAsIList = (IList<int>)testList;
+      
+      testListAsIList.InsertionSort(1, 5, Comparer<int>.Default);
+
+      CollectionAssert.AreEqual(
+        new List<int>(capacity: 7) { 9, 1, 2, 3, 4, 5, 0 },
+        testList
+      );
+    }
+
+  }
+
+} // namespace Nuclex.Support.Collections
+
+#endif // UNITTEST

Source/Collections/IListExtensions.cs

@@ -0,0 +1,86 @@
+#region CPL License
+/*
+Nuclex Framework
+Copyright (C) 2002-2017 Nuclex Development Labs
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the IBM Common Public License as
+published by the IBM Corporation; either version 1.0 of the
+License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+IBM Common Public License for more details.
+
+You should have received a copy of the IBM Common Public
+License along with this library
+*/
+#endregion
+
+using System;
+using System.Collections;
+using System.Collections.Generic;
+
+namespace Nuclex.Support.Collections {
+
+  /// <summary>Extension methods for the IList interface</summary>
+  public static class ListExtensions {
+
+    /// <summary>
+    ///   Sorts a subset of the elements in an IList&lt;T&gt; using the insertion sort algorithm
+    /// </summary>
+    /// <typeparam name="TElement">Type of elements the list contains</typeparam>
+    /// <param name="list">List in which a subset will be sorted</param>
+    /// <param name="startIndex">Index at which the sorting process will begin</param>
+    /// <param name="count">Index one past the last element that will be sorted</param>
+    /// <param name="comparer">Comparison function to use for comparing list elements</param>
+    public static void InsertionSort<TElement>(
+      this IList<TElement> list, int startIndex, int count, IComparer<TElement> comparer
+    ) {
+      int index = startIndex;
+      int endIndex = startIndex + count - 1;
+
+      while(index < endIndex) {
+        int rightIndex = index;
+        
+        ++index;
+        TElement temp = list[index];
+
+        while(rightIndex >= startIndex) {
+          if(comparer.Compare(list[rightIndex], temp) < 0) {
+            break;
+          }
+
+          list[rightIndex + 1] = list[rightIndex];
+          --rightIndex;
+        }
+
+        list[rightIndex + 1] = temp;
+      }
+    }
+
+    /// <summary>
+    ///   Sorts all the elements in an IList&lt;T&gt; using the insertion sort algorithm
+    /// </summary>
+    /// <typeparam name="TElement">Type of elements the list contains</typeparam>
+    /// <param name="list">List in which a subset will be sorted</param>
+    /// <param name="comparer">Comparison function to use for comparing list elements</param>
+    public static void InsertionSort<TElement>(
+      this IList<TElement> list, IComparer<TElement> comparer
+    ) {
+      InsertionSort(list, 0, list.Count, comparer);
+    }
+
+    /// <summary>
+    ///   Sorts all the elements in an IList&lt;T&gt; using the insertion sort algorithm
+    /// </summary>
+    /// <typeparam name="TElement">Type of elements the list contains</typeparam>
+    /// <param name="list">List in which a subset will be sorted</param>
+    public static void InsertionSort<TElement>(this IList<TElement> list) {
+      InsertionSort(list, Comparer<TElement>.Default);
+    }
+
+  }
+
+} // namespace Nuclex.Support.Collections