Improved deserialization to work as serialization

src/MongoDB.Bson/IO/BsonBinaryReaderSettings.cs

@@ -136,7 +136,8 @@ protected override BsonReaderSettings CloneImplementation()
                 Encoding = _encoding,
                 FixOldBinarySubTypeOnInput = _fixOldBinarySubTypeOnInput,
                 FixOldDateTimeMaxValueOnInput = _fixOldDateTimeMaxValueOnInput,
-                MaxDocumentSize = _maxDocumentSize
+                MaxDocumentSize = _maxDocumentSize,
+                SerializationDomain = SerializationDomain,  //TODO This can be improved
             };
 
             return clone;

src/MongoDB.Bson/IO/BsonDocumentReaderSettings.cs

@@ -67,7 +67,7 @@ public static BsonDocumentReaderSettings Defaults
         /// <returns>A clone of the settings.</returns>
         protected override BsonReaderSettings CloneImplementation()
         {
-            var clone = new BsonDocumentReaderSettings();
+            var clone = new BsonDocumentReaderSettings { SerializationDomain = SerializationDomain }; //TODO This can be improved
             return clone;
         }
     }

src/MongoDB.Bson/IO/BsonReaderSettings.cs

@@ -14,6 +14,7 @@
 */
 
 using System;
+using MongoDB.Bson.Serialization;
 
 namespace MongoDB.Bson.IO
 {
@@ -24,6 +25,7 @@ public abstract class BsonReaderSettings
     {
         // private fields
         private bool _isFrozen;
+        private IBsonSerializationDomain _serializationDomain;
 
         // constructors
         /// <summary>
@@ -77,6 +79,19 @@ public BsonReaderSettings FrozenCopy()
             }
         }
 
+        /// <summary>
+        /// //TODO
+        /// </summary>
+        public IBsonSerializationDomain SerializationDomain
+        {
+            get => _serializationDomain;
+            set
+            {
+                if (_isFrozen) { ThrowFrozenException(); }
+                _serializationDomain = value;
+            }
+        }
+
         // protected methods
         /// <summary>
         /// Creates a clone of the settings.

src/MongoDB.Bson/IO/IBsonReader.cs

@@ -62,7 +62,7 @@ public interface IBsonReader : IDisposable
         /// <summary>
         /// Pops the settings.
         /// </summary>
-        void PopSettings();
+        void PopSettings();  //TODO Why do we have push and pop methods? They are not used
 
         /// <summary>
         /// Pushes new settings for the reader.
@@ -246,6 +246,11 @@ public interface IBsonReader : IDisposable
         /// <param name="bookmark">The bookmark.</param>
         void ReturnToBookmark(BsonReaderBookmark bookmark);
 
+        /// <summary>
+        /// Gets the settings of the reader.
+        /// </summary>
+        BsonReaderSettings Settings { get;  }
+
         /// <summary>
         /// Skips the name (reader must be positioned on a name).
         /// </summary>

src/MongoDB.Bson/IO/JsonReaderSettings.cs

@@ -68,7 +68,7 @@ public static JsonReaderSettings Defaults
         /// <returns>A clone of the settings.</returns>
         protected override BsonReaderSettings CloneImplementation()
         {
-            var clone = new JsonReaderSettings();
+            var clone = new JsonReaderSettings { SerializationDomain = SerializationDomain }; //TODO This can be improved
             return clone;
         }
     }

src/MongoDB.Bson/Serialization/BsonDeserializationContext.cs

@@ -15,8 +15,6 @@
 
 using System;
 using MongoDB.Bson.IO;
-using MongoDB.Bson.Serialization.Options;
-using MongoDB.Bson.Serialization.Serializers;
 
 namespace MongoDB.Bson.Serialization
 {
@@ -37,14 +35,13 @@ private BsonDeserializationContext(
             IBsonReader reader,
             bool allowDuplicateElementNames,
             IBsonSerializer dynamicArraySerializer,
-            IBsonSerializer dynamicDocumentSerializer,
-            IBsonSerializationDomain domain)
+            IBsonSerializer dynamicDocumentSerializer)
         {
             _reader = reader;
             _allowDuplicateElementNames = allowDuplicateElementNames;
             _dynamicArraySerializer = dynamicArraySerializer;
             _dynamicDocumentSerializer = dynamicDocumentSerializer;
-            _domain = domain;
+            _domain = reader.Settings.SerializationDomain ?? BsonSerializer.DefaultDomain;
         }
 
         // public properties
@@ -221,23 +218,14 @@ public IBsonReader Reader
                 get { return _reader; }
             }
 
-            /// <summary>
-            /// //TODO
-            /// </summary>
-            public IBsonSerializationDomain Domain
-            {
-                get => _domain;
-                set => _domain = value;
-            }
-
             // public methods
             /// <summary>
             /// Builds the BsonDeserializationContext instance.
             /// </summary>
             /// <returns>A BsonDeserializationContext.</returns>
             internal BsonDeserializationContext Build()
             {
-                return new BsonDeserializationContext(_reader, _allowDuplicateElementNames, _dynamicArraySerializer, _dynamicDocumentSerializer, _domain);
+                return new BsonDeserializationContext(_reader, _allowDuplicateElementNames, _dynamicArraySerializer, _dynamicDocumentSerializer);
             }
         }
     }

src/MongoDB.Bson/Serialization/BsonSerializationDomain.cs

@@ -18,25 +18,21 @@ namespace MongoDB.Bson.Serialization
     internal class BsonSerializationDomain : IBsonSerializationDomainInternal, IDisposable
     {
         // private fields
-        private ReaderWriterLockSlim _configLock =
-            new ReaderWriterLockSlim(LockRecursionPolicy.SupportsRecursion);
+        private ReaderWriterLockSlim _configLock = new(LockRecursionPolicy.SupportsRecursion);
 
-        private Dictionary<Type, IIdGenerator> _idGenerators = new Dictionary<Type, IIdGenerator>();
+        private Dictionary<Type, IIdGenerator> _idGenerators = new();
 
-        private Dictionary<Type, IDiscriminatorConvention> _discriminatorConventions =
-            new Dictionary<Type, IDiscriminatorConvention>();
+        private Dictionary<Type, IDiscriminatorConvention> _discriminatorConventions = new();
 
-        private Dictionary<BsonValue, HashSet<Type>> _discriminators =
-            new Dictionary<BsonValue, HashSet<Type>>();
+        private Dictionary<BsonValue, HashSet<Type>> _discriminators = new();
 
-        private HashSet<Type> _discriminatedTypes = new HashSet<Type>();
+        private HashSet<Type> _discriminatedTypes = new();
         private BsonSerializerRegistry _serializerRegistry;
 
         private TypeMappingSerializationProvider _typeMappingSerializationProvider;
 
         // ConcurrentDictionary<Type, object> is being used as a concurrent set of Type. The values will always be null.
-        private ConcurrentDictionary<Type, object> _typesWithRegisteredKnownTypes =
-            new ConcurrentDictionary<Type, object>();
+        private ConcurrentDictionary<Type, object> _typesWithRegisteredKnownTypes = new();
 
         private bool _useNullIdChecker = false;
         private bool _useZeroIdChecker = false;

src/MongoDB.Driver/Core/Operations/CursorBatchDeserializationHelper.cs

@@ -44,6 +44,8 @@ public static List<TDocument> DeserializeBatch<TDocument>(RawBsonArray batch, IB
             if (messageEncoderSettings != null)
             {
                 readerSettings.Encoding = messageEncoderSettings.GetOrDefault(MessageEncoderSettingsName.ReadEncoding, Utf8Encodings.Strict);
+                readerSettings.SerializationDomain =
+                    messageEncoderSettings.GetOrDefault<IBsonSerializationDomain>(MessageEncoderSettingsName.SerializationDomain, null);
             };
 
             using (var stream = new ByteBufferStream(batch.Slice, ownsBuffer: false))