SortAndBind uses Move instead of RemoveAt/Insert when applicable. (#936)

Co-authored-by: Kristian Pettersen <[email protected]>

src/DynamicData/Binding/SortAndBind.cs

@@ -192,8 +192,7 @@ private void ApplyChanges(IChangeSet<TObject, TKey> changes)
                             updatedIndex = currentIndex < updatedIndex ? updatedIndex - 1 : updatedIndex;
                             if (updatedIndex != currentIndex)
                             {
-                                target.RemoveAt(currentIndex);
-                                target.Insert(updatedIndex, item);
+                                target.Move(currentIndex, updatedIndex, item);
                             }
                         }
                         break;

src/DynamicData/Cache/Internal/SortExtensions.cs

@@ -2,6 +2,8 @@
 // Roland Pheasant licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for full license information.
 
+using System.Collections.ObjectModel;
+
 namespace DynamicData.Cache.Internal;
 
 internal static class SortExtensions
@@ -51,4 +53,22 @@ public static int GetInsertPositionLinear<TItem>(this IList<TItem> list, TItem t
 
         return list.Count;
     }
+
+    public static void Move<TItem>(this IList<TItem> list, int original, int destination, TItem item)
+    {
+        // If the list supports the Move method, use it instead of removing and inserting.
+        if (list is IExtendedList<TItem> extendedList)
+        {
+            extendedList.Move(original, destination);
+        }
+        else if (list is ObservableCollection<TItem> observableList)
+        {
+            observableList.Move(original, destination);
+        }
+        else
+        {
+            list.RemoveAt(original);
+            list.Insert(destination, item);
+        }
+    }
 }