From bd2608d1df05f41ba18bd6d996fb407ce2d78a14 Mon Sep 17 00:00:00 2001
From: Adam Sitnik <adam.sitnik@gmail.com>
Date: Mon, 26 Aug 2024 15:53:42 +0200
Subject: [PATCH] Don't use WeakReferences in the round trip test, as the
 target may get freed in the meantime, fixes #104905

---
 .../BinaryFormatTests/FormattedObject/BasicObjectTests.cs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/libraries/System.Resources.Extensions/tests/BinaryFormatTests/FormattedObject/BasicObjectTests.cs b/src/libraries/System.Resources.Extensions/tests/BinaryFormatTests/FormattedObject/BasicObjectTests.cs
index b316a3e32b502..fd5fdc9b8c01a 100644
--- a/src/libraries/System.Resources.Extensions/tests/BinaryFormatTests/FormattedObject/BasicObjectTests.cs
+++ b/src/libraries/System.Resources.Extensions/tests/BinaryFormatTests/FormattedObject/BasicObjectTests.cs
@@ -14,6 +14,14 @@ public class BasicObjectTests : Common.BasicObjectTests<FormattedObjectSerialize
     [MemberData(nameof(SerializableObjects))]
     public void BasicObjectsRoundTripAndMatch(object value, TypeSerializableValue[] _)
     {
+        if (value is WeakReference || (value.GetType().IsGenericType && value.GetType().GetGenericTypeDefinition() == typeof(WeakReference<>)))
+        {
+            // We can root the provided value, but we can't root the deserialized value:
+            // GC can free the target of WeakReference after it gets deserialized,
+            // but before it gets returned from BinaryFormatter.Deserialize.
+            return;
+        }
+
         // We need to round trip through the BinaryFormatter as a few objects in tests remove
         // serialized data on deserialization.
         BinaryFormatter formatter = new();