Refactoring of contributed code

Author: hazzik

src/NHibernate.Test/NHSpecificTest/NH3408/Fixture.cs

@@ -1,22 +1,22 @@
+using System.Linq;
 using NHibernate.Linq;
 using NUnit.Framework;
 
 namespace NHibernate.Test.NHSpecificTest.NH3408
 {
-	using System.Linq;
-
 	public class Fixture : BugTestCase
 	{
 		[Test]
 		public void ProjectAnonymousTypeWithArrayProperty()
 		{
 			using (var session = OpenSession())
+			using (session.BeginTransaction())
 			{
 				var query = from c in session.Query<Country>()
 							select new { c.Picture, c.NationalHolidays };
 
-				var result = query.ToList();
+				Assert.DoesNotThrow(() => { query.ToList(); });
 			}
 		}
 	}
-}
+}

src/NHibernate.Test/NHSpecificTest/NH3408/Model.cs

@@ -1,7 +1,7 @@
+using System;
+
 namespace NHibernate.Test.NHSpecificTest.NH3408
 {
-	using System;
-
 	public class Country
 	{
 		public virtual int Id { get; set; }
@@ -12,4 +12,4 @@ public class Country
 
 		public virtual DateTime[] NationalHolidays { get; set; }
 	}
-}
+}

src/NHibernate/Linq/NestedSelects/NestedSelectDetector.cs

@@ -1,21 +1,19 @@
 using System.Collections.Generic;
 using System.Linq.Expressions;
+using System.Reflection;
 using NHibernate.Linq.Visitors;
 using Remotion.Linq.Clauses.Expressions;
 
 namespace NHibernate.Linq.NestedSelects
 {
-	using System.Reflection;
-	using NHibernate.Metadata;
-
 	internal class NestedSelectDetector : NhExpressionTreeVisitor
 	{
+		private readonly ISessionFactory sessionFactory;
 		private readonly ICollection<Expression> _expressions = new List<Expression>();
-		private readonly IDictionary<string, ICollectionMetadata> _collectionMetadata;
 
-		public NestedSelectDetector(IDictionary<string, ICollectionMetadata> collectionMetadata)
+		public NestedSelectDetector(ISessionFactory sessionFactory)
 		{
-			_collectionMetadata = collectionMetadata;
+			this.sessionFactory = sessionFactory;
 		}
 
 		public ICollection<Expression> Expressions
@@ -53,9 +51,9 @@ protected override Expression VisitMemberExpression(MemberExpression expression)
 
 		private bool IsMappedCollection(MemberInfo memberInfo)
 		{
-			var key = memberInfo.DeclaringType.FullName + "." + memberInfo.Name;
+			var collectionRole = memberInfo.DeclaringType.FullName + "." + memberInfo.Name;
 
-			return _collectionMetadata.ContainsKey(key);
+			return sessionFactory.GetCollectionMetadata(collectionRole) != null;
 		}
 	}
-}
+}

src/NHibernate/Linq/NestedSelects/NestedSelectRewriter.cs

@@ -8,6 +8,7 @@
 using NHibernate.Linq.Clauses;
 using NHibernate.Linq.GroupBy;
 using NHibernate.Linq.Visitors;
+using NHibernate.Util;
 using Remotion.Linq;
 using Remotion.Linq.Clauses.Expressions;
 
@@ -19,7 +20,7 @@ internal static class NestedSelectRewriter
 
 		public static void ReWrite(QueryModel queryModel, ISessionFactory sessionFactory)
 		{
-			var nsqmv = new NestedSelectDetector(sessionFactory.GetAllCollectionMetadata());
+			var nsqmv = new NestedSelectDetector(sessionFactory);
 			nsqmv.VisitExpression(queryModel.SelectClause.Selector);
 			if (!nsqmv.HasSubqueries)
 				return;
@@ -113,8 +114,8 @@ private static Expression ProcessSubquery(ISessionFactory sessionFactory, IColle
 		private static Expression ProcessMemberExpression(ISessionFactory sessionFactory, ICollection<ExpressionHolder> elementExpression, QueryModel queryModel, Expression @group, Expression memberExpression)
 		{
 			var join = new NhJoinClause(new NameGenerator(queryModel).GetNewName(),
-													GetElementType((MemberExpression) memberExpression),
-													memberExpression);
+										GetElementType(memberExpression.Type),
+										memberExpression);
 
 			queryModel.BodyClauses.Add(@join);
 
@@ -248,25 +249,12 @@ private static Expression ConvertToObject(Expression expression)
 			return Expression.Convert(expression, typeof(object));
 		}
 
-		private static System.Type GetElementType(MemberExpression expression)
+		private static System.Type GetElementType(System.Type type)
 		{
-			var type = expression.Type;
-			if (!type.IsCollectionType())
-			{
-				throw new ArgumentException();
-			}
-
-			if (type.IsGenericType)
-			{
-				return type.GetGenericArguments()[0];
-			}
-
-			if (type.IsArray)
-			{
-				return type.GetElementType();
-			}
-
-			throw new NotSupportedException("Unknown collection type " + type.FullName);
+			var elementType = ReflectHelper.GetCollectionElementType(type);
+			if (elementType == null)
+				throw new NotSupportedException("Unknown collection type " + type.FullName);
+			return elementType;
 		}
 	}
 }