Added basic support for IEnumerable<T> for both instance and mem… (#343)

* Added failing test.

* Added basic support for IEnumerable<T> for both instance and member property definitions.

* Adding documentation.

src/ExtendedXmlSerializer/Configuration/ElementDecorationContext.cs

@@ -31,5 +31,14 @@ public sealed class ElementDecorationContext<T> where T : IElement
 		/// <returns>The configured repository.</returns>
 		public IServiceRepository When(ISpecification<TypeInfo> specification)
 			=> new ConditionalElementDecoration<T>(specification).Get(_repository);
+
+		/// <summary>
+		/// Configures the container's <see cref="IElement"/> to use the decorated type when the provided specification is
+		/// satisfied.
+		/// </summary>
+		/// <typeparam name="TSpecification">The type of specification to activate via service location.</typeparam>
+		/// <returns>The configured repository</returns>
+		public IServiceRepository When<TSpecification>() where TSpecification : ISpecification<TypeInfo>
+			=> ConditionalElementDecoration<TSpecification, T>.Default.Get(_repository);
 	}
 }

src/ExtendedXmlSerializer/ContentModel/Collections/ArrayContents.cs

@@ -21,6 +21,4 @@ public ISerializer Get(CollectionContentInput parameter)
 			=> new Serializer(new ArrayReader(_contents, _classification, parameter.Classification, parameter.Item),
 			                  new EnumerableWriter(_enumerators, parameter.Item).Adapt());
 	}
-
-	// ATTRIBUTION: https://stackoverflow.com/a/1183019/3602057
 }

src/ExtendedXmlSerializer/ContentModel/Content/Container.cs

@@ -2,8 +2,8 @@ namespace ExtendedXmlSerializer.ContentModel.Content
 {
 	class Container<T> : SerializerAdapter<T>
 	{
-		public Container(IWriter<T> element, ISerializer<T> content) :
-			base(content, new Enclosure<T>(element, content)) {}
+		public Container(IWriter<T> element, ISerializer<T> content)
+			: base(content, new Enclosure<T>(element, content)) {}
 	}
 
 	sealed class Container : Container<object>

src/ExtendedXmlSerializer/ContentModel/Content/RuntimeElement.cs

@@ -1,7 +1,7 @@
-using System.Reflection;
 using ExtendedXmlSerializer.ContentModel.Collections;
 using ExtendedXmlSerializer.Core.Sources;
 using ExtendedXmlSerializer.ReflectionModel;
+using System.Reflection;
 
 namespace ExtendedXmlSerializer.ContentModel.Content
 {

src/ExtendedXmlSerializer/ContentModel/Content/Serializers.cs

@@ -16,7 +16,8 @@ public Serializers(IElement element, IContents contents)
 		public ISerializer Get(TypeInfo parameter)
 		{
 			var element = _element.Get(parameter);
-			return new Container(element, _contents.Get(parameter));
+			var result  = new Container(element, _contents.Get(parameter));
+			return result;
 		}
 	}
 }

src/ExtendedXmlSerializer/ContentModel/Members/MemberContents.cs

@@ -1,15 +1,24 @@
 using ExtendedXmlSerializer.Core.Sources;
 using ExtendedXmlSerializer.Core.Specifications;
+using JetBrains.Annotations;
 
 namespace ExtendedXmlSerializer.ContentModel.Members
 {
-	sealed class MemberContents : DecoratedSource<IMember, ISerializer>, IMemberContents
+	interface IMemberContentsCore : IMemberContents {}
+
+	[UsedImplicitly]
+	sealed class MemberContentsCore : DecoratedSource<IMember, ISerializer>, IMemberContentsCore
 	{
 		readonly static ISpecification<IMember> Specification = VariableTypeMemberSpecifications.Default.IfAssigned();
 
-		public MemberContents(DefaultMemberContents @default, VariableTypeMemberContents variable,
-		                      RegisteredMemberContents registered)
-			: base(@default.Let(Specification, variable)
-			               .Let(registered, registered)) {}
+		public MemberContentsCore(DefaultMemberContents @default, VariableTypeMemberContents variable)
+			: base(@default.Let(Specification, variable)) {}
+	}
+
+	[UsedImplicitly]
+	sealed class MemberContents : DecoratedSource<IMember, ISerializer>, IMemberContents
+	{
+		public MemberContents(IMemberContentsCore core, RegisteredMemberContents registered)
+			: base(core.Let(registered, registered)) {}
 	}
 }

src/ExtendedXmlSerializer/ContentModel/Members/MemberListWriter.cs

@@ -17,8 +17,7 @@ public void Write(IFormatWriter writer, object instance)
 				var length = members.Length;
 				for (var i = 0; i < length; i++)
 				{
-					members[i]
-						.Write(writer, instance);
+					members[i].Write(writer, instance);
 				}
 			}
 			else

src/ExtendedXmlSerializer/ContentModel/Members/VariableTypeMemberSpecifications.cs

@@ -5,9 +5,8 @@
 
 namespace ExtendedXmlSerializer.ContentModel.Members
 {
-	sealed class VariableTypeMemberSpecifications
-		: ReferenceCacheBase<IMember, IVariableTypeSpecification>,
-		  IVariableTypeMemberSpecifications
+	sealed class VariableTypeMemberSpecifications : ReferenceCacheBase<IMember, IVariableTypeSpecification>,
+	                                                IVariableTypeMemberSpecifications
 	{
 		public static VariableTypeMemberSpecifications Default { get; } = new VariableTypeMemberSpecifications();
 

src/ExtendedXmlSerializer/ContentModel/RuntimeSerialization.cs

@@ -1,6 +1,6 @@
+using ExtendedXmlSerializer.ContentModel.Content;
 using System;
 using System.Reflection;
-using ExtendedXmlSerializer.ContentModel.Content;
 
 namespace ExtendedXmlSerializer.ContentModel
 {

src/ExtendedXmlSerializer/ContentModel/RuntimeSerializer.cs

@@ -1,8 +1,8 @@
-using System.Reflection;
 using ExtendedXmlSerializer.ContentModel.Content;
 using ExtendedXmlSerializer.ContentModel.Format;
 using ExtendedXmlSerializer.ContentModel.Reflection;
 using JetBrains.Annotations;
+using System.Reflection;
 
 namespace ExtendedXmlSerializer.ContentModel
 {

src/ExtendedXmlSerializer/ExtensionMethodsForContent.cs

@@ -45,6 +45,18 @@ public static ElementDecorationContext<T> DecorateElementWith<T>(this IServiceRe
 
 		/* Extension Model: */
 
+		/// <summary>
+		/// Adds support for instances and property types that are explicitly specified as `IEnumerable{T}`.  If an object is
+		/// of a type of `IEnumerable` (essentially, a deferred query), it will be evaluated as a <see cref="List{T}"/> and
+		/// saved as such as required by either the instance or property in the object graph.
+		/// </summary>
+		/// <param name="this">The configuration container to configure.</param>
+		/// <returns>The configured configuration container.</returns>
+		/// <seealso href="https://github.com/ExtendedXmlSerializer/home/issues/340" />
+		/// <seealso href="https://twitter.com/vcsjones/status/1204432274000879619" />
+		public static IConfigurationContainer WithEnumerableSupport(this IConfigurationContainer @this)
+			=> @this.Extend(EnumerableSupportExtension.Default);
+
 		/// <summary>
 		/// Assigns a default serialization monitor for a configuration container.  A serialization monitor is a component
 		/// that gets notified whenever there is a serialization such as OnSerializing, OnSerialized, as well as

src/ExtendedXmlSerializer/ExtensionModel/Content/ConditionalElementDecoration.cs

@@ -1,7 +1,11 @@
-using System.Reflection;
 using ExtendedXmlSerializer.ContentModel;
 using ExtendedXmlSerializer.ContentModel.Content;
+using ExtendedXmlSerializer.Core;
+using ExtendedXmlSerializer.Core.Sources;
 using ExtendedXmlSerializer.Core.Specifications;
+using ExtendedXmlSerializer.ReflectionModel;
+using System.Linq;
+using System.Reflection;
 
 namespace ExtendedXmlSerializer.ExtensionModel.Content
 {
@@ -19,4 +23,27 @@ sealed class Factory
 			public IElement Create(IElement element, T arg2) => new ConditionalElement(_specification, arg2, element);
 		}
 	}
+
+	sealed class ConditionalElementDecoration<TSpecification, T> : IAlteration<IServiceRepository>
+		where T : IElement where TSpecification : ISpecification<TypeInfo>
+	{
+		public static ConditionalElementDecoration<TSpecification, T> Default { get; } =
+			new ConditionalElementDecoration<TSpecification, T>();
+
+		ConditionalElementDecoration() {}
+
+		public IServiceRepository Get(IServiceRepository parameter)
+		{
+			var key = Support<TSpecification>.Metadata;
+			var repository = key.IsClass &&
+			                 !parameter.AvailableServices.Contains(key)
+				                 ? parameter.RegisterWithDependencies<TSpecification>()
+				                 : parameter;
+			return repository.RegisterWithDependencies<T>()
+			                 .Decorate<IElement>(Create);
+		}
+
+		static IElement Create(IServiceProvider arg1, IElement arg2)
+			=> new ConditionalElement(arg1.Get<TSpecification>(), arg1.Get<T>(), arg2);
+	}
 }

src/ExtendedXmlSerializer/ExtensionModel/Content/ContentModelExtension.cs

@@ -6,7 +6,6 @@
 using ExtendedXmlSerializer.Core;
 using ExtendedXmlSerializer.Core.Sources;
 using ExtendedXmlSerializer.ReflectionModel;
-using VariableTypeSpecification = ExtendedXmlSerializer.ReflectionModel.VariableTypeSpecification;
 
 namespace ExtendedXmlSerializer.ExtensionModel.Content
 {
@@ -42,8 +41,6 @@ public IServiceRepository Get(IServiceRepository parameter)
 			=> parameter.Register<RuntimeElement>()
 			            .Register<Element>()
 			            .Register<IElement, Element>()
-			            .DecorateElementWith<VariableTypeElement>()
-			            .When(VariableTypeSpecification.Default)
 			            .DecorateElementWith<GenericElement>()
 			            .When(IsGenericTypeSpecification.Default)
 			            .DecorateElementWith<ArrayElement>()

src/ExtendedXmlSerializer/ExtensionModel/Content/Contents.cs

@@ -24,22 +24,31 @@ public sealed class Contents : ISerializerExtension
 		public IServiceRepository Get(IServiceRepository parameter)
 			=> parameter.RegisterConstructorDependency<IContents>((provider, info) => provider.Get<DeferredContents>())
 			            .Register<IContents, RuntimeContents>()
+
 			            .DecorateContentsWith<MemberedContents>()
 			            .When<IActivatingTypeSpecification>()
+
 			            .DecorateContentsWith<DefaultCollections>()
 			            .When<DefaultCollectionSpecification>()
+
 			            .Register<IDictionaryEntries, DictionaryEntries>()
 			            .DecorateContentsWith<DictionaryContents>()
 			            .When<DictionaryContentSpecification>()
+
 			            .DecorateContentsWith<Arrays>()
 			            .When(ArraySpecification.Default)
+
 			            .DecorateContentsWith<MappedArrayContents>()
 			            .Then()
+
 			            .RegisterInstance(ReflectionSerializer.Default)
+
 			            .DecorateContentsWith<ReflectionContents>()
 			            .When(ReflectionContentSpecification.Default)
+
 			            .DecorateContentsWith<NullableContents>()
 			            .When(IsNullableTypeSpecification.Default)
+
 			            .DecorateContentsWith<ConverterContents>()
 			            .When<ConverterSpecification>()
 			            .DecorateContentsWith<RegisteredContents>()