CSHARP-3315: Implement Equals for serializers.

Author: rstam

src/MongoDB.Bson/MongoDB.Bson.csproj

@@ -20,7 +20,9 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Compile Include="..\MongoDB.Shared\Hasher.cs" Link="Hasher.cs" />
+    <Compile Include="..\MongoDB.Shared\DictionaryComparer.cs" Link="Shared\DictionaryComparer.cs" />
+    <Compile Include="..\MongoDB.Shared\Hasher.cs" Link="Shared\Hasher.cs" />
+    <Compile Include="..\MongoDB.Shared\SequenceComparer.cs" Link="Shared\SequenceComparer.cs" />
   </ItemGroup>
 
 </Project>

src/MongoDB.Bson/Serialization/BsonClassMap.cs

@@ -19,10 +19,10 @@
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
-using System.Runtime.CompilerServices;
 using System.Runtime.Serialization;
 using MongoDB.Bson.IO;
 using MongoDB.Bson.Serialization.Conventions;
+using MongoDB.Shared;
 
 namespace MongoDB.Bson.Serialization
 {
@@ -542,6 +542,35 @@ public object CreateInstance()
             return creator.Invoke();
         }
 
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                GetType().Equals(obj.GetType()) &&
+                obj is BsonClassMap other &&
+                _frozen.Equals(true) &&  other._frozen.Equals(true) && // BsonClassMaps should only be equal if they are frozen
+                object.Equals(_baseClassMap, other._baseClassMap) &&
+                object.Equals(_classType, other._classType) &&
+                object.Equals(_creator, other._creator) &&
+                SequenceComparer.Equals(_creatorMaps, other._creatorMaps) &&
+                SequenceComparer.Equals(_declaredMemberMaps, other._declaredMemberMaps) &&
+                object.Equals(_discriminator, other._discriminator) &&
+                _discriminatorIsRequired.Equals(other._discriminatorIsRequired) &&
+                _extraElementsMemberIndex.Equals(other._extraElementsMemberIndex) &&
+                object.Equals(_extraElementsMemberMap, other._extraElementsMemberMap) &&
+                _hasRootClass.Equals(other._hasRootClass) &&
+                object.Equals(_idMemberMap, other._idMemberMap) &&
+                _ignoreExtraElements.Equals(other._ignoreExtraElements) &&
+                _ignoreExtraElementsIsInherited.Equals(other._ignoreExtraElementsIsInherited) &&
+                _isRootClass.Equals(other._isRootClass) &&
+                SequenceComparer.Equals(_knownTypes, other._knownTypes);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
+
         /// <summary>
         /// Freezes the class map.
         /// </summary>

src/MongoDB.Bson/Serialization/BsonMemberMap.cs

@@ -264,6 +264,32 @@ public void Freeze()
             _frozen = true;
         }
 
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                GetType().Equals(obj.GetType()) &&
+                obj is BsonMemberMap other &&
+                _frozen.Equals(true) && other._frozen.Equals(true) && // BsonMemberMaps should only be equal if they are frozen
+                object.Equals(_defaultValue, other._defaultValue) &&
+                object.Equals(_defaultValueCreator, other._defaultValueCreator) &&
+                _defaultValueSpecified.Equals(other._defaultValueSpecified) &&
+                object.Equals(_elementName, other._elementName) &&
+                object.Equals(_idGenerator, other._idGenerator) &&
+                _ignoreIfDefault.Equals(other._ignoreIfDefault) &&
+                _ignoreIfNull.Equals(other._ignoreIfNull) &&
+                _isRequired.Equals(other._isRequired) &&
+                object.Equals(_memberInfo, other._memberInfo) &&
+                _order.Equals(other._order) &&
+                object.Equals(_serializer, other._serializer) &&
+                object.Equals(_shouldSerializeMethod, other._shouldSerializeMethod);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
+
         /// <summary>
         /// Gets the serializer.
         /// </summary>

src/MongoDB.Bson/Serialization/BsonSerializationInfo.cs

@@ -127,6 +127,23 @@ public object DeserializeValue(BsonValue value)
             }
         }
 
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                GetType().Equals(obj.GetType()) &&
+                obj is BsonSerializationInfo other &&
+                object.Equals(_elementName, other._elementName) &&
+                object.Equals(_elementPath, other._elementPath) &&
+                object.Equals(_nominalType, other._nominalType) &&
+                object.Equals(_serializer, other._serializer);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
+
         /// <summary>
         /// Merges the new BsonSerializationInfo by taking its properties and concatenating its ElementName.
         /// </summary>

src/MongoDB.Bson/Serialization/Conventions/ObjectDiscriminatorConvention.cs

@@ -69,6 +69,17 @@ public string ElementName
         }
 
         // public methods
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                GetType().Equals(obj.GetType()) &&
+                obj is ObjectDiscriminatorConvention other &&
+                object.Equals(_elementName, other._elementName);
+        }
+
         /// <summary>
         /// Gets the actual type of an object by reading the discriminator from a BsonReader.
         /// </summary>
@@ -143,5 +154,8 @@ public BsonValue GetDiscriminator(Type nominalType, Type actualType)
         {
             return TypeNameDiscriminator.GetDiscriminator(actualType);
         }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
     }
 }

src/MongoDB.Bson/Serialization/Conventions/StandardDiscriminatorConvention.cs

@@ -77,6 +77,17 @@ public string ElementName
         }
 
         // public methods
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                GetType().Equals(obj.GetType()) &&
+                obj is StandardDiscriminatorConvention other &&
+                object.Equals(_elementName, other._elementName);
+        }
+
         /// <summary>
         /// Gets the actual type of an object by reading the discriminator from a BsonReader.
         /// </summary>
@@ -123,5 +134,8 @@ public Type GetActualType(IBsonReader bsonReader, Type nominalType)
         /// <param name="actualType">The actual type.</param>
         /// <returns>The discriminator value.</returns>
         public abstract BsonValue GetDiscriminator(Type nominalType, Type actualType);
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
     }
 }

src/MongoDB.Bson/Serialization/Options/RepresentationConverter.cs

@@ -14,7 +14,6 @@
 */
 
 using System;
-using MongoDB.Bson.Serialization.Attributes;
 
 namespace MongoDB.Bson.Serialization.Options
 {
@@ -57,6 +56,21 @@ public bool AllowTruncation
         }
 
         // public methods
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                GetType().Equals(obj.GetType()) &&
+                obj is RepresentationConverter other &&
+                _allowOverflow.Equals(other._allowOverflow) &&
+                _allowTruncation.Equals(other._allowTruncation);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
+
         /// <summary>
         /// Converts a Decimal128 to a Decimal.
         /// </summary>

src/MongoDB.Bson/Serialization/Serializers/BitArraySerializer.cs

@@ -34,7 +34,6 @@ private static class Flags
 
         // private fields
         private readonly SerializerHelper _helper;
-        private readonly Int32Serializer _int32Serializer = new Int32Serializer();
         private readonly BsonType _representation;
 
         // constructors
@@ -85,6 +84,21 @@ public BsonType Representation
         }
 
         // public methods
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                base.Equals(obj) &&
+                obj is BitArraySerializer other &&
+                _representation.Equals(other._representation);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
+
+        // protected methods
 #pragma warning disable 618 // about obsolete BsonBinarySubType.OldBinary
         /// <summary>
         /// Deserializes a value.
@@ -110,7 +124,7 @@ protected override BitArray DeserializeValue(BsonDeserializationContext context,
                     {
                         switch (flag)
                         {
-                            case Flags.Length: length = _int32Serializer.Deserialize(context); break;
+                            case Flags.Length: length = Int32Serializer.Instance.Deserialize(context); break;
                             case Flags.Bytes: bytes = bsonReader.ReadBytes(); break;
                         }
                     });

src/MongoDB.Bson/Serialization/Serializers/BooleanSerializer.cs

@@ -121,6 +121,20 @@ public override bool Deserialize(BsonDeserializationContext context, BsonDeseria
             }
         }
 
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            if (object.ReferenceEquals(obj, null)) { return false; }
+            if (object.ReferenceEquals(this, obj)) { return true; }
+            return
+                base.Equals(obj) &&
+                obj is BooleanSerializer other &&
+                _representation.Equals(other._representation);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode() => 0;
+
         /// <summary>
         /// Serializes a value.
         /// </summary>

src/MongoDB.Bson/Serialization/Serializers/BsonArraySerializer.cs

@@ -13,7 +13,6 @@
 * limitations under the License.
 */
 
-
 namespace MongoDB.Bson.Serialization.Serializers
 {
     /// <summary>