Merge pull request #7786 from timunie/fix/DataGridCopyClearsContent

Fix: DataGrid copying data clears DataGridCells

src/Avalonia.Base/Data/BindingOperations.cs

@@ -99,14 +99,15 @@ namespace Avalonia.Data
 
         private sealed class TwoWayBindingDisposable : IDisposable
         {
-            private readonly IDisposable _first;
-            private readonly IDisposable _second;
+            private readonly IDisposable _toTargetSubscription;
+            private readonly IDisposable _fromTargetSubsription;
+
             private bool _isDisposed;
 
-            public TwoWayBindingDisposable(IDisposable first, IDisposable second)
+            public TwoWayBindingDisposable(IDisposable toTargetSubscription, IDisposable fromTargetSubsription)
             {
-                _first = first;
-                _second = second;
+                _toTargetSubscription = toTargetSubscription;
+                _fromTargetSubsription = fromTargetSubsription;
             }
 
             public void Dispose()
@@ -116,8 +117,8 @@ namespace Avalonia.Data
                     return;
                 }
 
-                _first.Dispose();
-                _second.Dispose();
+                _fromTargetSubsription.Dispose();
+                _toTargetSubscription.Dispose();
 
                 _isDisposed = true;
             }

tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Binding.cs

@@ -829,6 +829,30 @@ namespace Avalonia.Base.UnitTests
             subscription.Dispose();
         }
 
+        [Fact]
+        public void TwoWay_Binding_Should_Not_Call_Setter_On_Creation_With_Value()
+        {
+            var target = new Class1();
+            var source = new TestTwoWayBindingViewModel() { Value = 1 };
+            source.ResetSetterCalled();
+
+            target.Bind(Class1.DoubleValueProperty, new Binding(nameof(source.Value), BindingMode.TwoWay) { Source = source });
+
+            Assert.False(source.SetterCalled);
+        }
+
+        [Fact]
+        public void TwoWay_Binding_Should_Not_Call_Setter_On_Creation_Indexer_With_Value()
+        {
+            var target = new Class1();
+            var source = new TestTwoWayBindingViewModel() { [0] = 1 };
+            source.ResetSetterCalled();
+
+            target.Bind(Class1.DoubleValueProperty, new Binding("[0]", BindingMode.TwoWay) { Source = source });
+
+            Assert.False(source.SetterCalled);
+        }
+
         /// <summary>
         /// Returns an observable that returns a single value but does not complete.
         /// </summary>
@@ -943,6 +967,11 @@ namespace Avalonia.Base.UnitTests
             }
 
             public bool SetterCalled { get; private set; }
+
+            public void ResetSetterCalled()
+            {
+                SetterCalled = false;
+            }
         }
     }
 }