From 9e4a5972253cbdb550f64c1a71b73746e09b2649 Mon Sep 17 00:00:00 2001
From: Steven Kirk <grokys@gmail.com>
Date: Tue, 12 Jul 2022 14:12:45 +0200
Subject: [PATCH] Added failing tests for #8480.

---
 .../ClassesTests.cs                           | 31 +++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/tests/Avalonia.Controls.UnitTests/ClassesTests.cs b/tests/Avalonia.Controls.UnitTests/ClassesTests.cs
index c10e7b467c..bcd2b6ec1f 100644
--- a/tests/Avalonia.Controls.UnitTests/ClassesTests.cs
+++ b/tests/Avalonia.Controls.UnitTests/ClassesTests.cs
@@ -168,5 +168,36 @@ namespace Avalonia.Controls.UnitTests
 
             Assert.Equal(new[] { "foo" }, target);
         }
+
+        [Fact]
+        public void Listeners_Can_Be_Added_By_Listener()
+        {
+            var classes = new Classes();
+            var listener1 = new ClassesChangedListener(() => { });
+            var listener2 = new ClassesChangedListener(() => classes.AddListener(listener1));
+
+            classes.AddListener(listener2);
+            classes.Add("bar");
+        }
+
+        [Fact]
+        public void Listeners_Can_Be_Removed_By_Listener()
+        {
+            var classes = new Classes();
+            var listener1 = new ClassesChangedListener(() => { });
+            var listener2 = new ClassesChangedListener(() => classes.RemoveListener(listener1));
+
+            classes.AddListener(listener1);
+            classes.AddListener(listener2);
+            classes.Add("bar");
+        }
+
+        private class ClassesChangedListener : IClassesChangedListener
+        {
+            private Action _action;
+
+            public ClassesChangedListener(Action action) => _action = action;
+            public void Changed() => _action();
+        }
     }
 }