From 06a4a1af5ba992355441c4440af75b3e30b72160 Mon Sep 17 00:00:00 2001
From: Dariusz Komosinski <darek.komosinski@gmail.com>
Date: Sun, 15 Sep 2019 01:29:17 +0200
Subject: [PATCH 1/3] Add failing unit test.

---
 .../WeakEventHandlerManagerTests.cs           | 20 +++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/tests/Avalonia.Base.UnitTests/WeakEventHandlerManagerTests.cs b/tests/Avalonia.Base.UnitTests/WeakEventHandlerManagerTests.cs
index 9ed6590821..81b882308d 100644
--- a/tests/Avalonia.Base.UnitTests/WeakEventHandlerManagerTests.cs
+++ b/tests/Avalonia.Base.UnitTests/WeakEventHandlerManagerTests.cs
@@ -36,7 +36,7 @@ namespace Avalonia.Base.UnitTests
         }
 
         [Fact]
-        public void EventShoudBePassedToSubscriber()
+        public void EventShouldBePassedToSubscriber()
         {
             bool handled = false;
             var subscriber = new Subscriber(() => handled = true);
@@ -47,7 +47,23 @@ namespace Avalonia.Base.UnitTests
             Assert.True(handled);
         }
 
- 
+        [Fact]
+        public void EventShouldNotBeRaisedAfterUnsubscribe()
+        {
+            bool handled = false;
+            var subscriber = new Subscriber(() => handled = true);
+            var source = new EventSource();
+            WeakEventHandlerManager.Subscribe<EventSource, EventArgs, Subscriber>(source, "Event",
+                subscriber.OnEvent);
+
+            WeakEventHandlerManager.Unsubscribe<EventArgs, Subscriber>(source, "Event",
+                subscriber.OnEvent);
+
+            source.Fire();
+
+            Assert.False(handled);
+        }
+
         [Fact]
         public void EventHandlerShouldNotBeKeptAlive()
         {

From 3030427c07d3d38c869a42aab0ad44e64b7dcc18 Mon Sep 17 00:00:00 2001
From: Dariusz Komosinski <darek.komosinski@gmail.com>
Date: Sun, 15 Sep 2019 01:33:32 +0200
Subject: [PATCH 2/3] Fix unsubscribe not doing anything due to wrong check.

---
 src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs b/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs
index b59ed166bc..607e2a147b 100644
--- a/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs
+++ b/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs
@@ -161,9 +161,8 @@ namespace Avalonia.Utilities
                 for (int c = 0; c < _count; ++c)
                 {
                     var reference = _data[c].Subscriber;
-                    TSubscriber instance;
 
-                    if (reference != null && reference.TryGetTarget(out instance) && instance == s)
+                    if (reference != null && reference.TryGetTarget(out TSubscriber instance) && instance == (TSubscriber)s.Target)
                     {
                         _data[c] = default;
                         removed = true;

From 213600f6c23b247d561727963face70b23d7fec3 Mon Sep 17 00:00:00 2001
From: Dariusz Komosinski <darek.komosinski@gmail.com>
Date: Sun, 15 Sep 2019 01:47:04 +0200
Subject: [PATCH 3/3] Use Equals.

---
 src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs b/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs
index 607e2a147b..f4cec98628 100644
--- a/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs
+++ b/src/Avalonia.Base/Utilities/WeakEventHandlerManager.cs
@@ -162,7 +162,7 @@ namespace Avalonia.Utilities
                 {
                     var reference = _data[c].Subscriber;
 
-                    if (reference != null && reference.TryGetTarget(out TSubscriber instance) && instance == (TSubscriber)s.Target)
+                    if (reference != null && reference.TryGetTarget(out TSubscriber instance) && Equals(instance, s.Target))
                     {
                         _data[c] = default;
                         removed = true;