Refactor serializer generation layer to simplify exceptional flow.

yfakariya · yfakariya · commit fb1db57b4edc · 2015-04-26T15:48:52.000+09:00
diff --git a/src/MsgPack/Serialization/AbstractSerializers/ISerializerBuilder.cs b/src/MsgPack/Serialization/AbstractSerializers/ISerializerBuilder.cs
@@ -33,11 +33,12 @@ internal interface ISerializerBuilder<TObject>
 		///		Builds the serializer and returns its new instance.
 		/// </summary>
 		/// <param name="context">The context information.</param>
+		/// <param name="concreteType">The substitution type if <typeparamref name="TObject"/> is abstract type. <c>null</c> when <typeparamref name="TObject"/> is not abstract type.</param>
 		/// <param name="schema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value may be <c>null</c>.</param>
 		/// <returns>
 		///		Newly created serializer object.
 		///		This value will not be <c>null</c>.
 		/// </returns>
-		MessagePackSerializer<TObject> BuildSerializerInstance( SerializationContext context, PolymorphismSchema schema );
+		MessagePackSerializer<TObject> BuildSerializerInstance( SerializationContext context, Type concreteType, PolymorphismSchema schema );
 	}
 }
diff --git a/src/MsgPack/Serialization/AbstractSerializers/ISerializerCodeGenerator.cs b/src/MsgPack/Serialization/AbstractSerializers/ISerializerCodeGenerator.cs
@@ -34,13 +34,14 @@ internal interface ISerializerCodeGenerator
 		/// <param name="context">
 		///		The <see cref="ISerializerCodeGenerationContext"/> which holds configuration and stores generated code constructs.
 		/// </param>
+		/// <param name="concreteType">The substitution type if builder's target type is abstract type. <c>null</c> when builder's target type is not abstract type.</param>
 		/// <param name="itemSchema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value must not be <c>null</c>.</param>
 		/// <exception cref="ArgumentNullException">
 		///		<paramref name="context"/> is <c>null</c>.
 		/// </exception>
 		/// <exception cref="NotSupportedException">
 		///		This class does not support code generation.
 		/// </exception>
-		void BuildSerializerCode( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema );
+		void BuildSerializerCode( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema );
 	}
 }
diff --git a/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilderContract`3.cs b/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilderContract`3.cs
@@ -41,7 +41,7 @@ protected override TContext CreateCodeGenerationContextForSerializerCreation( Se
 		}
 
 #if !NETFX_CORE && !SILVERLIGHT
-		protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )
+		protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )
 		{
 			Contract.Requires( context != null );
 		}
diff --git a/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilder`3.Array.cs b/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilder`3.Array.cs
@@ -25,10 +25,10 @@ namespace MsgPack.Serialization.AbstractSerializers
 {
 	partial class SerializerBuilder<TContext, TConstruct, TObject>
 	{
-		private void BuildArraySerializer( TContext context, CollectionTraits traits, PolymorphismSchema itemsSchema )
+		private void BuildArraySerializer( TContext context, Type concreteType, CollectionTraits traits, PolymorphismSchema itemsSchema )
 		{
 			this.BuildCollectionPackTo( context, traits, itemsSchema );
-			this.BuildCollectionUnpackFrom( context, traits, itemsSchema );
+			this.BuildCollectionUnpackFrom( context, concreteType, traits, itemsSchema );
 			if ( traits.AddMethod != null )
 			{
 				this.BuildCollectionUnpackTo( context, traits, itemsSchema );
@@ -99,26 +99,14 @@ private TConstruct EmitInvokeEnumerableToArrayExpression( TContext context, TCon
 			return this.EmitInvokeMethodExpression( context, null, Metadata._Enumerable.ToArray1Method.MakeGenericMethod( elementType ), enumerable );
 		}
 
-		private void BuildCollectionUnpackFrom( TContext context, CollectionTraits traits, PolymorphismSchema itemsSchema )
+		private void BuildCollectionUnpackFrom( TContext context, Type concreteType, CollectionTraits traits, PolymorphismSchema itemsSchema )
 		{
 			this.EmitMethodPrologue( context, SerializerMethod.UnpackFromCore );
 
 			TConstruct construct = null;
 			try
 			{
-				Type instanceType;
-				if ( typeof( TObject ).GetIsInterface() || typeof( TObject ).GetIsAbstract() )
-				{
-					instanceType = context.SerializationContext.DefaultCollectionTypes.GetConcreteType( typeof( TObject ) );
-					if ( instanceType == null )
-					{
-						throw SerializationExceptions.NewNotSupportedBecauseCannotInstanciateAbstractType( typeof( TObject ) );
-					}
-				}
-				else
-				{
-					instanceType = typeof( TObject );
-				}
+				var instanceType = concreteType ?? typeof( TObject );
 
 				/*
 				 *	if (!unpacker.IsArrayHeader)
diff --git a/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilder`3.Map.cs b/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilder`3.Map.cs
@@ -26,10 +26,10 @@ namespace MsgPack.Serialization.AbstractSerializers
 {
 	partial class SerializerBuilder<TContext, TConstruct, TObject>
 	{
-		private void BuildMapSerializer( TContext context, CollectionTraits traits, PolymorphismSchema keysSchema, PolymorphismSchema valuesSchema )
+		private void BuildMapSerializer( TContext context, Type concreteType, CollectionTraits traits, PolymorphismSchema keysSchema, PolymorphismSchema valuesSchema )
 		{
 			this.BuildMapPackTo( context, traits, keysSchema, valuesSchema );
-			this.BuildMapUnpackFrom( context );
+			this.BuildMapUnpackFrom( context, concreteType );
 			this.BuildMapUnpackTo( context, traits, keysSchema, valuesSchema );
 		}
 
@@ -121,25 +121,13 @@ private TConstruct EmitPackKeyValuePair( TContext context, CollectionTraits trai
 				);
 		}
 
-		private void BuildMapUnpackFrom( TContext context )
+		private void BuildMapUnpackFrom( TContext context, Type concreteType )
 		{
 			this.EmitMethodPrologue( context, SerializerMethod.UnpackFromCore );
 			TConstruct construct = null;
 			try
 			{
-				Type instanceType;
-				if ( typeof( TObject ).GetIsInterface() || typeof( TObject ).GetIsAbstract() )
-				{
-					instanceType = context.SerializationContext.DefaultCollectionTypes.GetConcreteType( typeof( TObject ) );
-					if ( instanceType == null )
-					{
-						throw SerializationExceptions.NewNotSupportedBecauseCannotInstanciateAbstractType( typeof( TObject ) );
-					}
-				}
-				else
-				{
-					instanceType = typeof( TObject );
-				}
+				var instanceType = concreteType ?? typeof( TObject );
 
 				/*
 				 *	if (!unpacker.IsMapHeader)
diff --git a/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilder`3.cs b/src/MsgPack/Serialization/AbstractSerializers/SerializerBuilder`3.cs
@@ -21,8 +21,6 @@
 using System;
 using System.Diagnostics.Contracts;
 
-using MsgPack.Serialization.DefaultSerializers;
-
 namespace MsgPack.Serialization.AbstractSerializers
 {
 	/// <summary>
@@ -52,20 +50,15 @@ protected SerializerBuilder() { }
 		///		Builds the serializer and returns its new instance.
 		/// </summary>
 		/// <param name="context">The context information.</param>
+		/// <param name="concreteType">The substitution type if <typeparamref name="TObject"/> is abstract type. <c>null</c> when <typeparamref name="TObject"/> is not abstract type.</param>
 		/// <param name="schema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value may be <c>null</c>.</param>
 		/// <returns>
 		///		Newly created serializer object.
 		///		This value will not be <c>null</c>.
 		/// </returns>
 		[System.Diagnostics.CodeAnalysis.SuppressMessage( "Microsoft.Design", "CA1062:ValidateArgumentsOfPublicMethods", MessageId = "0", Justification = "Asserted internally" )]
-		public MessagePackSerializer<TObject> BuildSerializerInstance( SerializationContext context, PolymorphismSchema schema )
+		public MessagePackSerializer<TObject> BuildSerializerInstance( SerializationContext context, Type concreteType, PolymorphismSchema schema )
 		{
-			var genericSerializer = GenericSerializer.Create<TObject>( context, schema );
-			if ( genericSerializer != null )
-			{
-				return genericSerializer;
-			}
-
 			Func<SerializationContext, MessagePackSerializer<TObject>> constructor;
 			var codeGenerationContext = this.CreateCodeGenerationContextForSerializerCreation( context );
 			if ( typeof( TObject ).GetIsEnum() )
@@ -75,7 +68,7 @@ public MessagePackSerializer<TObject> BuildSerializerInstance( SerializationCont
 			}
 			else
 			{
-				this.BuildSerializer( codeGenerationContext, schema );
+				this.BuildSerializer( codeGenerationContext, concreteType, schema );
 				constructor = this.CreateSerializerConstructor( codeGenerationContext );
 			}
 
@@ -105,12 +98,13 @@ public MessagePackSerializer<TObject> BuildSerializerInstance( SerializationCont
 		///		Builds the serializer and returns its new instance.
 		/// </summary>
 		/// <param name="context">The context information. This value will not be <c>null</c>.</param>
+		/// <param name="concreteType">The substitution type if <typeparamref name="TObject"/> is abstract type. <c>null</c> when <typeparamref name="TObject"/> is not abstract type.</param>
 		/// <param name="schema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value may be <c>null</c>.</param>
 		/// <returns>
 		///		Newly created serializer object.
 		///		This value will not be <c>null</c>.
 		/// </returns>
-		protected void BuildSerializer( TContext context, PolymorphismSchema schema )
+		protected void BuildSerializer( TContext context, Type concreteType, PolymorphismSchema schema )
 		{
 #if DEBUG
 			Contract.Assert( !typeof( TObject ).IsArray );
@@ -121,13 +115,13 @@ protected void BuildSerializer( TContext context, PolymorphismSchema schema )
 			{
 				case CollectionKind.Array:
 				{
-					this.BuildArraySerializer( context, traits, ( schema ?? PolymorphismSchema.Default ).ItemSchema );
+					this.BuildArraySerializer( context, concreteType, traits, ( schema ?? PolymorphismSchema.Default ).ItemSchema );
 					break;
 				}
 				case CollectionKind.Map:
 				{
 					var itemSchema = ( schema ?? PolymorphismSchema.Default );
-					this.BuildMapSerializer( context, traits, itemSchema.KeySchema, itemSchema.ItemSchema );
+					this.BuildMapSerializer( context, concreteType, traits, itemSchema.KeySchema, itemSchema.ItemSchema );
 					break;
 				}
 				case CollectionKind.NotCollection:
@@ -186,6 +180,7 @@ TContext codeGenerationContext
 		/// <param name="context">
 		///		The <see cref="ISerializerCodeGenerationContext"/> which holds configuration and stores generated code constructs.
 		/// </param>
+		/// <param name="concreteType">The substitution type if <typeparamref name="TObject"/> is abstract type. <c>null</c> when <typeparamref name="TObject"/> is not abstract type.</param>
 		/// <param name="itemSchema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value must not be <c>null</c>.</param>
 		/// <exception cref="ArgumentNullException">
 		///		<paramref name="context"/> is <c>null</c>.
@@ -196,7 +191,7 @@ TContext codeGenerationContext
 		/// <remarks>
 		///		This method will not do anything when <see cref="ISerializerCodeGenerationContext.BuiltInSerializerExists"/> returns <c>true</c> for <typeparamref name="TObject"/>.
 		/// </remarks>
-		public void BuildSerializerCode( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )
+		public void BuildSerializerCode( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )
 		{
 			if ( context == null )
 			{
@@ -209,7 +204,7 @@ public void BuildSerializerCode( ISerializerCodeGenerationContext context, Polym
 				return;
 			}
 
-			this.BuildSerializerCodeCore( context, itemSchema );
+			this.BuildSerializerCodeCore( context, concreteType, itemSchema );
 		}
 
 		/// <summary>
@@ -219,11 +214,12 @@ public void BuildSerializerCode( ISerializerCodeGenerationContext context, Polym
 		///		The <see cref="ISerializerCodeGenerationContext"/> which holds configuration and stores generated code constructs.
 		///		This value will not be <c>null</c>.
 		/// </param>
+		/// <param name="concreteType">The substitution type if <typeparamref name="TObject"/> is abstract type. <c>null</c> when <typeparamref name="TObject"/> is not abstract type.</param>
 		/// <param name="itemSchema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value must not be <c>null</c>.</param>
 		/// <exception cref="NotSupportedException">
 		///		This class does not support code generation.
 		/// </exception>
-		protected virtual void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )
+		protected virtual void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )
 		{
 			throw new NotSupportedException();
 		}
diff --git a/src/MsgPack/Serialization/CodeDomSerializers/CodeDomSerializerBuilder`1.cs b/src/MsgPack/Serialization/CodeDomSerializers/CodeDomSerializerBuilder`1.cs
@@ -907,7 +907,7 @@ protected override CodeDomConstruct EmitEnumToUnderlyingCastExpression(
 			return CodeDomConstruct.Expression( underlyingType, new CodeCastExpression( underlyingType, enumValue.AsExpression() ) );
 		}
 
-		protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )
+		protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )
 		{
 			var asCodeDomContext = context as CodeDomContext;
 			if ( asCodeDomContext == null )
@@ -920,7 +920,7 @@ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContex
 
 			asCodeDomContext.Reset( typeof( TObject ) );
 
-			this.BuildSerializer( asCodeDomContext, itemSchema );
+			this.BuildSerializer( asCodeDomContext, concreteType, itemSchema );
 			this.Finish( asCodeDomContext, typeof( TObject ).GetIsEnum() );
 		}
 
diff --git a/src/MsgPack/Serialization/EmittingSerializers/AssemblyBuilderSerializerBuilder`1.cs b/src/MsgPack/Serialization/EmittingSerializers/AssemblyBuilderSerializerBuilder`1.cs
@@ -126,7 +126,7 @@ protected override AssemblyBuilderEmittingContext CreateCodeGenerationContextFor
 		}
 
 #if !SILVERLIGHT
-		protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )
+		protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )
 		{
 			var asAssemblyBuilderCodeGenerationContext = context as AssemblyBuilderCodeGenerationContext;
 			if ( asAssemblyBuilderCodeGenerationContext == null )
@@ -142,7 +142,7 @@ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContex
 					typeof( TObject )
 				);
 
-			this.BuildSerializer( emittingContext, itemSchema );
+			this.BuildSerializer( emittingContext, concreteType, itemSchema );
 			// Finish type creation, and discard returned ctor.
 			emittingContext.Emitter.CreateConstructor<TObject>();
 		}
diff --git a/src/MsgPack/Serialization/MessagePackSerializer.cs b/src/MsgPack/Serialization/MessagePackSerializer.cs
@@ -301,7 +301,7 @@ internal static MessagePackSerializer<T> CreateInternal<T>( SerializationContext
 #endif // !XAMIOS && !XAMDROID && !UNITY
 #endif // NETFX_CORE else
 #if !XAMIOS && !XAMDROID && !UNITY
-			return builder.BuildSerializerInstance( context, schema == null ? null : schema.FilterSelf() );
+			return builder.BuildSerializerInstance( context, concreteType, schema == null ? null : schema.FilterSelf() );
 #endif // !XAMIOS && !XAMDROID && !UNITY
 		}
 
diff --git a/src/MsgPack/Serialization/SerializerGenerator.cs b/src/MsgPack/Serialization/SerializerGenerator.cs
@@ -343,7 +343,14 @@ public IEnumerable<string> Generate( IEnumerable<Type> targetTypes, TConfig conf
 				foreach ( var targetType in targetTypes.Distinct() )
 				{
 					var generator = generatorFactory( targetType );
-					generator.BuildSerializerCode( generationContext, null );
+
+					var concreteType = default( Type );
+					if ( targetType.GetIsInterface() || targetType.GetIsAbstract() )
+					{
+						concreteType = context.DefaultCollectionTypes.GetConcreteType( targetType );
+					}
+
+					generator.BuildSerializerCode( generationContext, concreteType, null );
 				}
 
 				Directory.CreateDirectory( configuration.OutputDirectory );
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayCodeDomBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayCodeDomBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class ArrayCodeDomBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Array, EmitterFlavor = EmitterFlavor.CodeDomBased };
-			return ( new CodeDomSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new CodeDomSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayContextBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayContextBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class ArrayContextBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Array, EmitterFlavor = EmitterFlavor.ContextBased };
-			return ( new DynamicMethodSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new DynamicMethodSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayExpressionBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayExpressionBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class ArrayExpressionBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Array, EmitterFlavor = EmitterFlavor.ExpressionBased };
-			return ( new ExpressionTreeSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new ExpressionTreeSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayFieldBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/ArrayFieldBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class ArrayFieldBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Array, EmitterFlavor = EmitterFlavor.FieldBased };
-			return ( new AssemblyBuilderSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new AssemblyBuilderSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/CustomCollectionSerializersTest.ttinclude b/test/MsgPack.UnitTest.BclExtensions/Serialization/CustomCollectionSerializersTest.ttinclude
@@ -55,7 +55,7 @@ namespace MsgPack.Serialization
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.<#= serializationMethod #>, EmitterFlavor = EmitterFlavor.<#=  emitterFlavor #> };
-			return ( new <#= builderTypeName #><T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new <#= builderTypeName #><T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/MapCodeDomBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/MapCodeDomBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class MapCodeDomBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Map, EmitterFlavor = EmitterFlavor.CodeDomBased };
-			return ( new CodeDomSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new CodeDomSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/MapContextBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/MapContextBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class MapContextBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Map, EmitterFlavor = EmitterFlavor.ContextBased };
-			return ( new DynamicMethodSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new DynamicMethodSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/MapExpressionBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/MapExpressionBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class MapExpressionBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Map, EmitterFlavor = EmitterFlavor.ExpressionBased };
-			return ( new ExpressionTreeSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new ExpressionTreeSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest.BclExtensions/Serialization/MapFieldBasedCustomCollectionSerializersTest.cs b/test/MsgPack.UnitTest.BclExtensions/Serialization/MapFieldBasedCustomCollectionSerializersTest.cs
@@ -52,7 +52,7 @@ public class MapFieldBasedImmutableCollectionsTest
 		private MessagePackSerializer<T> CreateTarget<T>()
 		{
 			var context = new SerializationContext() { SerializationMethod = SerializationMethod.Map, EmitterFlavor = EmitterFlavor.FieldBased };
-			return ( new AssemblyBuilderSerializerBuilder<T>() ).BuildSerializerInstance( context, PolymorphismSchema.Default );
+			return ( new AssemblyBuilderSerializerBuilder<T>() ).BuildSerializerInstance( context, typeof( T ), PolymorphismSchema.Default );
 		}
 		
 		private bool CanDump
diff --git a/test/MsgPack.UnitTest/Serialization/CompositeTest.cs b/test/MsgPack.UnitTest/Serialization/CompositeTest.cs
diff --git a/test/MsgPack.UnitTest/Serialization/MessagePackSerializerTTest.cs b/test/MsgPack.UnitTest/Serialization/MessagePackSerializerTTest.cs

Original file line number	Diff line number	Diff line change
`@@ -33,11 +33,12 @@ internal interface ISerializerBuilder<TObject>`
`33`	`33`	`/// Builds the serializer and returns its new instance.`
`34`	`34`	`/// </summary>`
`35`	`35`	`/// <param name="context">The context information.</param>`
	`36`	`+ /// <param name="concreteType">The substitution type if <typeparamref name="TObject"/> is abstract type. <c>null</c> when <typeparamref name="TObject"/> is not abstract type.</param>`
`36`	`37`	`/// <param name="schema">The schema which contains schema for collection items, dictionary keys, or tuple items. This value may be <c>null</c>.</param>`
`37`	`38`	`/// <returns>`
`38`	`39`	`/// Newly created serializer object.`
`39`	`40`	`/// This value will not be <c>null</c>.`
`40`	`41`	`/// </returns>`
`41`		`- MessagePackSerializer<TObject> BuildSerializerInstance( SerializationContext context, PolymorphismSchema schema );`
	`42`	`+ MessagePackSerializer<TObject> BuildSerializerInstance( SerializationContext context, Type concreteType, PolymorphismSchema schema );`
`42`	`43`	`}`
`43`	`44`	`}`
Original file line number	Diff line number	Diff line change
`@@ -41,7 +41,7 @@ protected override TContext CreateCodeGenerationContextForSerializerCreation( Se`
`41`	`41`	`}`
`42`	`42`
`43`	`43`	`#if !NETFX_CORE && !SILVERLIGHT`
`44`		`- protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )`
	`44`	`+ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )`
`45`	`45`	`{`
`46`	`46`	`Contract.Requires( context != null );`
`47`	`47`	`}`
Original file line number	Diff line number	Diff line change
`@@ -25,10 +25,10 @@ namespace MsgPack.Serialization.AbstractSerializers`
`25`	`25`	`{`
`26`	`26`	`partial class SerializerBuilder<TContext, TConstruct, TObject>`
`27`	`27`	`{`
`28`		`- private void BuildArraySerializer( TContext context, CollectionTraits traits, PolymorphismSchema itemsSchema )`
	`28`	`+ private void BuildArraySerializer( TContext context, Type concreteType, CollectionTraits traits, PolymorphismSchema itemsSchema )`
`29`	`29`	`{`
`30`	`30`	`this.BuildCollectionPackTo( context, traits, itemsSchema );`
`31`		`- this.BuildCollectionUnpackFrom( context, traits, itemsSchema );`
	`31`	`+ this.BuildCollectionUnpackFrom( context, concreteType, traits, itemsSchema );`
`32`	`32`	`if ( traits.AddMethod != null )`
`33`	`33`	`{`
`34`	`34`	`this.BuildCollectionUnpackTo( context, traits, itemsSchema );`
`@@ -99,26 +99,14 @@ private TConstruct EmitInvokeEnumerableToArrayExpression( TContext context, TCon`
`99`	`99`	`return this.EmitInvokeMethodExpression( context, null, Metadata._Enumerable.ToArray1Method.MakeGenericMethod( elementType ), enumerable );`
`100`	`100`	`}`
`101`	`101`
`102`		`- private void BuildCollectionUnpackFrom( TContext context, CollectionTraits traits, PolymorphismSchema itemsSchema )`
	`102`	`+ private void BuildCollectionUnpackFrom( TContext context, Type concreteType, CollectionTraits traits, PolymorphismSchema itemsSchema )`
`103`	`103`	`{`
`104`	`104`	`this.EmitMethodPrologue( context, SerializerMethod.UnpackFromCore );`
`105`	`105`
`106`	`106`	`TConstruct construct = null;`
`107`	`107`	`try`
`108`	`108`	`{`
`109`		`- Type instanceType;`
`110`		`- if ( typeof( TObject ).GetIsInterface() \|\| typeof( TObject ).GetIsAbstract() )`
`111`		`- {`
`112`		`- instanceType = context.SerializationContext.DefaultCollectionTypes.GetConcreteType( typeof( TObject ) );`
`113`		`- if ( instanceType == null )`
`114`		`- {`
`115`		`- throw SerializationExceptions.NewNotSupportedBecauseCannotInstanciateAbstractType( typeof( TObject ) );`
`116`		`- }`
`117`		`- }`
`118`		`- else`
`119`		`- {`
`120`		`- instanceType = typeof( TObject );`
`121`		`- }`
	`109`	`+ var instanceType = concreteType ?? typeof( TObject );`
`122`	`110`
`123`	`111`	`/*`
`124`	`112`	`* if (!unpacker.IsArrayHeader)`
Original file line number	Diff line number	Diff line change
`@@ -26,10 +26,10 @@ namespace MsgPack.Serialization.AbstractSerializers`
`26`	`26`	`{`
`27`	`27`	`partial class SerializerBuilder<TContext, TConstruct, TObject>`
`28`	`28`	`{`
`29`		`- private void BuildMapSerializer( TContext context, CollectionTraits traits, PolymorphismSchema keysSchema, PolymorphismSchema valuesSchema )`
	`29`	`+ private void BuildMapSerializer( TContext context, Type concreteType, CollectionTraits traits, PolymorphismSchema keysSchema, PolymorphismSchema valuesSchema )`
`30`	`30`	`{`
`31`	`31`	`this.BuildMapPackTo( context, traits, keysSchema, valuesSchema );`
`32`		`- this.BuildMapUnpackFrom( context );`
	`32`	`+ this.BuildMapUnpackFrom( context, concreteType );`
`33`	`33`	`this.BuildMapUnpackTo( context, traits, keysSchema, valuesSchema );`
`34`	`34`	`}`
`35`	`35`
`@@ -121,25 +121,13 @@ private TConstruct EmitPackKeyValuePair( TContext context, CollectionTraits trai`
`121`	`121`	`);`
`122`	`122`	`}`
`123`	`123`
`124`		`- private void BuildMapUnpackFrom( TContext context )`
	`124`	`+ private void BuildMapUnpackFrom( TContext context, Type concreteType )`
`125`	`125`	`{`
`126`	`126`	`this.EmitMethodPrologue( context, SerializerMethod.UnpackFromCore );`
`127`	`127`	`TConstruct construct = null;`
`128`	`128`	`try`
`129`	`129`	`{`
`130`		`- Type instanceType;`
`131`		`- if ( typeof( TObject ).GetIsInterface() \|\| typeof( TObject ).GetIsAbstract() )`
`132`		`- {`
`133`		`- instanceType = context.SerializationContext.DefaultCollectionTypes.GetConcreteType( typeof( TObject ) );`
`134`		`- if ( instanceType == null )`
`135`		`- {`
`136`		`- throw SerializationExceptions.NewNotSupportedBecauseCannotInstanciateAbstractType( typeof( TObject ) );`
`137`		`- }`
`138`		`- }`
`139`		`- else`
`140`		`- {`
`141`		`- instanceType = typeof( TObject );`
`142`		`- }`
	`130`	`+ var instanceType = concreteType ?? typeof( TObject );`
`143`	`131`
`144`	`132`	`/*`
`145`	`133`	`* if (!unpacker.IsMapHeader)`
Original file line number	Diff line number	Diff line change
`@@ -907,7 +907,7 @@ protected override CodeDomConstruct EmitEnumToUnderlyingCastExpression(`
`907`	`907`	`return CodeDomConstruct.Expression( underlyingType, new CodeCastExpression( underlyingType, enumValue.AsExpression() ) );`
`908`	`908`	`}`
`909`	`909`
`910`		`- protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )`
	`910`	`+ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )`
`911`	`911`	`{`
`912`	`912`	`var asCodeDomContext = context as CodeDomContext;`
`913`	`913`	`if ( asCodeDomContext == null )`
`@@ -920,7 +920,7 @@ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContex`
`920`	`920`
`921`	`921`	`asCodeDomContext.Reset( typeof( TObject ) );`
`922`	`922`
`923`		`- this.BuildSerializer( asCodeDomContext, itemSchema );`
	`923`	`+ this.BuildSerializer( asCodeDomContext, concreteType, itemSchema );`
`924`	`924`	`this.Finish( asCodeDomContext, typeof( TObject ).GetIsEnum() );`
`925`	`925`	`}`
`926`	`926`
Original file line number	Diff line number	Diff line change
`@@ -126,7 +126,7 @@ protected override AssemblyBuilderEmittingContext CreateCodeGenerationContextFor`
`126`	`126`	`}`
`127`	`127`
`128`	`128`	`#if !SILVERLIGHT`
`129`		`- protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, PolymorphismSchema itemSchema )`
	`129`	`+ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContext context, Type concreteType, PolymorphismSchema itemSchema )`
`130`	`130`	`{`
`131`	`131`	`var asAssemblyBuilderCodeGenerationContext = context as AssemblyBuilderCodeGenerationContext;`
`132`	`132`	`if ( asAssemblyBuilderCodeGenerationContext == null )`
`@@ -142,7 +142,7 @@ protected override void BuildSerializerCodeCore( ISerializerCodeGenerationContex`
`142`	`142`	`typeof( TObject )`
`143`	`143`	`);`
`144`	`144`
`145`		`- this.BuildSerializer( emittingContext, itemSchema );`
	`145`	`+ this.BuildSerializer( emittingContext, concreteType, itemSchema );`
`146`	`146`	`// Finish type creation, and discard returned ctor.`
`147`	`147`	`emittingContext.Emitter.CreateConstructor<TObject>();`
`148`	`148`	`}`
Original file line number	Diff line number	Diff line change
`@@ -301,7 +301,7 @@ internal static MessagePackSerializer<T> CreateInternal<T>( SerializationContext`
`301`	`301`	`#endif // !XAMIOS && !XAMDROID && !UNITY`
`302`	`302`	`#endif // NETFX_CORE else`
`303`	`303`	`#if !XAMIOS && !XAMDROID && !UNITY`
`304`		`- return builder.BuildSerializerInstance( context, schema == null ? null : schema.FilterSelf() );`
	`304`	`+ return builder.BuildSerializerInstance( context, concreteType, schema == null ? null : schema.FilterSelf() );`
`305`	`305`	`#endif // !XAMIOS && !XAMDROID && !UNITY`
`306`	`306`	`}`
`307`	`307`