Optimize ListEx.Clone by using the is operator (#386)

Fix inconsistent indentation Add unit test for ListEx.Clone for Move on a plain List Co-authored-by: John Cummings <jcummings2sf@gmail.com>
reactivemarbles · Aug 1, 2020 · ef688db · ef688db
1 parent 6912429
commit ef688db
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Showing 2 changed files with 32 additions and 7 deletions.
diff --git a/src/DynamicData.Tests/List/CloneChangesFixture.cs b/src/DynamicData.Tests/List/CloneChangesFixture.cs
@@ -186,5 +186,32 @@ public void MovedItemInObservableCollectionIsMoved()
 
             itemMoved.Should().BeTrue();
         }
+
+        [Fact]
+        public void MovedItemInListLowerToHigherIsMoved()
+        {
+            _source.AddRange(Enumerable.Range(1, 10));
+            _source.Move(1, 2);
+
+            var changes = _source.CaptureChanges();
+
+            _clone.Clone(changes);
+
+            _clone.Should().BeEquivalentTo(_source);
+        }
+
+        [Fact]
+        public void MovedItemInListHigherToLowerIsMoved()
+        {
+            _source.AddRange(Enumerable.Range(1, 10));
+            _source.Move(2, 1);
+
+            var changes = _source.CaptureChanges();
+
+            _clone.Clone(changes);
+
+            _clone.Should().BeEquivalentTo(_source);
+        }
+
     }
 }
diff --git a/src/DynamicData/List/ListEx.cs b/src/DynamicData/List/ListEx.cs
@@ -228,17 +228,15 @@ private static void Clone<T>(this IList<T> source,  Change<T> item, IEqualityCom
                     var change = item.Item;
                     bool hasIndex = change.CurrentIndex >= 0;
                     if (!hasIndex)
-                        {
-                            throw new UnspecifiedIndexException("Cannot move as an index was not specified");
-                        }
+                    {
+                        throw new UnspecifiedIndexException("Cannot move as an index was not specified");
+                    }
 
-                        var extendedList = source as IExtendedList<T>;
-                    var observableCollection = source as ObservableCollection<T>;
-                    if (extendedList != null)
+                    if (source is IExtendedList<T> extendedList)
                     {
                         extendedList.Move(change.PreviousIndex, change.CurrentIndex);
                     }
-                    else if (observableCollection != null)
+                    else if (source is ObservableCollection<T> observableCollection)
                     {
                         observableCollection.Move(change.PreviousIndex, change.CurrentIndex);
                     }