Update SslClientAuthenticationOptionsExtensions.ShallowClone to copy CipherSuitesPolicy (#211)

src/libraries/Common/src/System/Net/Security/SslClientAuthenticationOptionsExtensions.cs

@@ -2,16 +2,25 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Collections.Generic;
+#if DEBUG
+using System.Collections;
+using System.Diagnostics;
+using System.Reflection;
+#endif
+
 namespace System.Net.Security
 {
     internal static class SslClientAuthenticationOptionsExtensions
     {
-        public static SslClientAuthenticationOptions ShallowClone(this SslClientAuthenticationOptions options) =>
-            new SslClientAuthenticationOptions()
+        public static SslClientAuthenticationOptions ShallowClone(this SslClientAuthenticationOptions options)
+        {
+            var clone = new SslClientAuthenticationOptions()
             {
                 AllowRenegotiation = options.AllowRenegotiation,
-                ApplicationProtocols = options.ApplicationProtocols,
+                ApplicationProtocols = options.ApplicationProtocols != null ? new List<SslApplicationProtocol>(options.ApplicationProtocols) : null,
                 CertificateRevocationCheckMode = options.CertificateRevocationCheckMode,
+                CipherSuitesPolicy = options.CipherSuitesPolicy,
                 ClientCertificates = options.ClientCertificates,
                 EnabledSslProtocols = options.EnabledSslProtocols,
                 EncryptionPolicy = options.EncryptionPolicy,
@@ -19,5 +28,50 @@ internal static class SslClientAuthenticationOptionsExtensions
                 RemoteCertificateValidationCallback = options.RemoteCertificateValidationCallback,
                 TargetHost = options.TargetHost
             };
+
+#if DEBUG
+            // Try to detect if a property gets added that we're not copying correctly.
+            foreach (PropertyInfo pi in options.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly))
+            {
+                object origValue = pi.GetValue(options);
+                object cloneValue = pi.GetValue(clone);
+
+                if (origValue is IEnumerable origEnumerable)
+                {
+                    IEnumerable cloneEnumerable = cloneValue as IEnumerable;
+                    Debug.Assert(cloneEnumerable != null, $"{pi.Name}. Expected enumerable cloned value.");
+
+                    IEnumerator e1 = origEnumerable.GetEnumerator();
+                    try
+                    {
+                        IEnumerator e2 = cloneEnumerable.GetEnumerator();
+                        try
+                        {
+                            while (e1.MoveNext())
+                            {
+                                Debug.Assert(e2.MoveNext(), $"{pi.Name}. Cloned enumerator too short.");
+                                Debug.Assert(Equals(e1.Current, e2.Current), $"{pi.Name}. Cloned enumerator's values don't match.");
+                            }
+                            Debug.Assert(!e2.MoveNext(), $"{pi.Name}. Cloned enumerator too long.");
+                        }
+                        finally
+                        {
+                            (e2 as IDisposable)?.Dispose();
+                        }
+                    }
+                    finally
+                    {
+                        (e1 as IDisposable)?.Dispose();
+                    }
+                }
+                else
+                {
+                    Debug.Assert(Equals(origValue, cloneValue), $"{pi.Name}. Expected: {origValue}, Actual: {cloneValue}");
+                }
+            }
+#endif
+
+            return clone;
+        }
     }
 }