From 7d8dcc02ecbd389726f6c82302121741fc3bb392 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Thu, 10 May 2018 00:53:10 +0200
Subject: [PATCH 1/3] Added failing test for #1568

---
 .../AvaloniaObjectTests_Attached.cs           | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs b/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs
index ab2a2d899d..2262f4cfa2 100644
--- a/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs
+++ b/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs
@@ -24,10 +24,23 @@ namespace Avalonia.Base.UnitTests
             Assert.Throws<IndexOutOfRangeException>(() => target.SetValue(Class2.FooProperty, "throw"));
         }
 
+        [Fact]
+        public void AvaloniaProperty_Initialized_Is_Called_For_Attached_Property()
+        {
+            bool raised = false;
+
+            using (Class1.FooProperty.Initialized.Subscribe(x => raised = true))
+            {
+                new Class3();
+            }
+
+            Assert.True(raised);
+        }
+
         private class Class1 : AvaloniaObject
         {
             public static readonly AttachedProperty<string> FooProperty =
-                AvaloniaProperty.RegisterAttached<Class1, Class2, string>(
+                AvaloniaProperty.RegisterAttached<Class1, AvaloniaObject, string>(
                     "Foo",
                     "foodefault",
                     validate: ValidateFoo);
@@ -48,5 +61,9 @@ namespace Avalonia.Base.UnitTests
             public static readonly AttachedProperty<string> FooProperty =
                 Class1.FooProperty.AddOwner<Class2>();
         }
+
+        private class Class3 : AvaloniaObject
+        {
+        }
     }
 }

From e4df163ef0fff967d3483642aa49fa4059554a50 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Thu, 10 May 2018 01:09:38 +0200
Subject: [PATCH 2/3] Call Initialized for attached properties.

#1499 broke `AvaloniaProperty.Initialized` for attached properties - they were no longer called.

Fixes #1568.
---
 src/Avalonia.Base/AvaloniaObject.cs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/Avalonia.Base/AvaloniaObject.cs b/src/Avalonia.Base/AvaloniaObject.cs
index 4ab813333d..68b9871fd1 100644
--- a/src/Avalonia.Base/AvaloniaObject.cs
+++ b/src/Avalonia.Base/AvaloniaObject.cs
@@ -71,7 +71,8 @@ namespace Avalonia
         public AvaloniaObject()
         {
             VerifyAccess();
-            foreach (var property in AvaloniaPropertyRegistry.Instance.GetRegistered(this))
+
+            void Notify(AvaloniaProperty property)
             {
                 object value = property.IsDirect ?
                     ((IDirectPropertyAccessor)property).GetValue(this) :
@@ -86,6 +87,16 @@ namespace Avalonia
 
                 property.NotifyInitialized(e);
             }
+
+            foreach (var property in AvaloniaPropertyRegistry.Instance.GetRegistered(this))
+            {
+                Notify(property);
+            }
+
+            foreach (var property in AvaloniaPropertyRegistry.Instance.GetRegisteredAttached(this.GetType()))
+            {
+                Notify(property);
+            }
         }
 
         /// <summary>

From 44fe6aa6acdbeb0fea761b2a136046356ce06a82 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Thu, 10 May 2018 01:31:28 +0200
Subject: [PATCH 3/3] Fix failing unit tests.

AvaloniaProperty registrations are for life (of the test runner) not for christmas.
---
 .../AvaloniaObjectTests_Attached.cs                  | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs b/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs
index 2262f4cfa2..02600f5e00 100644
--- a/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs
+++ b/tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Attached.cs
@@ -37,10 +37,14 @@ namespace Avalonia.Base.UnitTests
             Assert.True(raised);
         }
 
-        private class Class1 : AvaloniaObject
+        private class Base : AvaloniaObject
+        {
+        }
+
+        private class Class1 : Base
         {
             public static readonly AttachedProperty<string> FooProperty =
-                AvaloniaProperty.RegisterAttached<Class1, AvaloniaObject, string>(
+                AvaloniaProperty.RegisterAttached<Class1, Base, string>(
                     "Foo",
                     "foodefault",
                     validate: ValidateFoo);
@@ -56,13 +60,13 @@ namespace Avalonia.Base.UnitTests
             }
         }
 
-        private class Class2 : AvaloniaObject
+        private class Class2 : Base
         {
             public static readonly AttachedProperty<string> FooProperty =
                 Class1.FooProperty.AddOwner<Class2>();
         }
 
-        private class Class3 : AvaloniaObject
+        private class Class3 : Base
         {
         }
     }