From 4a7f9ee3fb4696457c97ceb1dbc264853db0323d Mon Sep 17 00:00:00 2001
From: Stephen Brown <steve@brown.bg>
Date: Fri, 11 Aug 2023 22:36:23 +0200
Subject: [PATCH] Fix #1370 by making copy of default AuthMechanisms

---
 projects/RabbitMQ.Client/client/api/ConnectionFactory.cs | 2 +-
 projects/Unit/TestConnectionFactory.cs                   | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs b/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs
index 7074ff4bcf..88971e137e 100644
--- a/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs
+++ b/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs
@@ -153,7 +153,7 @@ public sealed class ConnectionFactory : ConnectionFactoryBase, IAsyncConnectionF
         /// <summary>
         ///  SASL auth mechanisms to use.
         /// </summary>
-        public IList<IAuthMechanismFactory> AuthMechanisms { get; set; } = DefaultAuthMechanisms;
+        public IList<IAuthMechanismFactory> AuthMechanisms { get; set; } = DefaultAuthMechanisms.ToList();
 
         /// <summary>
         /// Address family used by default.
diff --git a/projects/Unit/TestConnectionFactory.cs b/projects/Unit/TestConnectionFactory.cs
index 3a990a529f..ecc3c74afb 100644
--- a/projects/Unit/TestConnectionFactory.cs
+++ b/projects/Unit/TestConnectionFactory.cs
@@ -279,5 +279,14 @@ public void TestCreateConnectioUsesValidEndpointWhenMultipleSupplied()
             var ep = new AmqpTcpEndpoint("localhost");
             using(IConnection conn = cf.CreateConnection(new List<AmqpTcpEndpoint> { invalidEp, ep })) {};
         }
+
+        [Test]
+        public void TestCreateConnectionTwiceDoesntClearAuthMechanisms()
+        {
+            var cf = new ConnectionFactory();
+            cf.AuthMechanisms.Clear();
+            var cf2 = new ConnectionFactory();
+            Assert.That(cf2.AuthMechanisms.Count, Is.EqualTo(1));
+        }
     }
 }