Refactoring

Author: hazzik

src/NHibernate/Linq/Clauses/NhJoinClause.cs

@@ -1,23 +1,32 @@
 using System.Linq.Expressions;
+using NHibernate.Linq.Visitors;
 using Remotion.Linq.Clauses;
 
-
-namespace NHibernate.Linq.Visitors
+namespace NHibernate.Linq.Clauses
 {
-    /// <summary>
-    /// All joins are created as outer joins. An optimization in <see cref="WhereJoinDetector"/> finds
-    /// joins that may be inner joined and calls <see cref="MakeInner"/> on them.
-    /// <see cref="QueryModelVisitor"/>'s <see cref="QueryModelVisitor.VisitAdditionalFromClause"/> will
-    /// then emit the correct HQL join.
-    /// </summary>
-    public class NhJoinClause : AdditionalFromClause
-    {
-        public bool IsInner { get; private set; }
-        public void MakeInner() {
-            IsInner = true;
-        }
-        public NhJoinClause(string itemName, System.Type itemType, Expression fromExpression) : base(itemName, itemType, fromExpression) {
-            IsInner = false;
-        }
-    }
-}
+	/// <summary>
+	/// All joins are created as outer joins. An optimization in <see cref="WhereJoinDetector"/> finds
+	/// joins that may be inner joined and calls <see cref="MakeInner"/> on them.
+	/// <see cref="QueryModelVisitor"/>'s <see cref="QueryModelVisitor.VisitAdditionalFromClause"/> will
+	/// then emit the correct HQL join.
+	/// </summary>
+	public class NhJoinClause : AdditionalFromClause
+	{
+		public NhJoinClause(string itemName, System.Type itemType, Expression fromExpression) : base(itemName, itemType, fromExpression)
+		{
+			IsInner = false;
+		}
+
+		public bool IsInner { get; private set; }
+
+		public static NhJoinClause Create(FromClauseBase fromClause)
+		{
+			return new NhJoinClause(fromClause.ItemName, fromClause.ItemType, fromClause.FromExpression);
+		}
+
+		public void MakeInner()
+		{
+			IsInner = true;
+		}
+	}
+}

src/NHibernate/Linq/NestedSelects/NestedSelectRewriter.cs

@@ -8,7 +8,6 @@
 using NHibernate.Linq.GroupBy;
 using NHibernate.Linq.Visitors;
 using Remotion.Linq;
-using Remotion.Linq.Clauses;
 
 namespace NHibernate.Linq.NestedSelects
 {
@@ -25,7 +24,7 @@ public static void ReWrite(QueryModel queryModel, ISessionFactory sessionFactory
 
 			var mainFromClause = subQueryModel.MainFromClause;
 
-			var item = new NhJoinClause(mainFromClause.ItemName, mainFromClause.ItemType, mainFromClause.FromExpression);
+			var item = NhJoinClause.Create(mainFromClause);
 
 			queryModel.BodyClauses.Add(item);
 

src/NHibernate/Linq/Visitors/JoinBuilder.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using System.Linq.Expressions;
+using NHibernate.Linq.Clauses;
 using Remotion.Linq;
 using Remotion.Linq.Clauses;
 using Remotion.Linq.Clauses.Expressions;

src/NHibernate/Linq/Visitors/QueryModelVisitor.cs

@@ -56,7 +56,7 @@ public static ExpressionToHqlTranslationResults GenerateHqlQuery(QueryModel quer
 
 			// rewrite any operators that should be applied on the outer query
 			// by flattening out the sub-queries that they are located in
-			ResultOperatorRewriterResult result = ResultOperatorRewriter.Rewrite(queryModel);
+			var result = ResultOperatorRewriter.Rewrite(queryModel);
 
 			// Identify and name query sources
 			QuerySourceIdentifier.Visit(parameters.QuerySourceNamer, queryModel);
@@ -142,22 +142,10 @@ public override void VisitAdditionalFromClause(AdditionalFromClause fromClause,
 		{
 			var querySourceName = VisitorParameters.QuerySourceNamer.GetName(fromClause);
 
-			if (fromClause is NhJoinClause)
+			var joinClause = fromClause as NhJoinClause;
+			if (joinClause != null)
 			{
-				if (((NhJoinClause)fromClause).IsInner)
-				{
-					_hqlTree.AddFromClause(
-						_hqlTree.TreeBuilder.Join(
-							HqlGeneratorExpressionTreeVisitor.Visit(fromClause.FromExpression, VisitorParameters).AsExpression(),
-							_hqlTree.TreeBuilder.Alias(querySourceName)));
-				}
-				else
-				{
-					_hqlTree.AddFromClause(
-						_hqlTree.TreeBuilder.LeftJoin(
-							HqlGeneratorExpressionTreeVisitor.Visit(fromClause.FromExpression, VisitorParameters).AsExpression(),
-							_hqlTree.TreeBuilder.Alias(querySourceName)));
-				}
+				VisitNhJoinClause(querySourceName, joinClause);
 			}
 			else if (fromClause.FromExpression is MemberExpression)
 			{
@@ -180,6 +168,24 @@ public override void VisitAdditionalFromClause(AdditionalFromClause fromClause,
 			base.VisitAdditionalFromClause(fromClause, queryModel, index);
 		}
 
+		private void VisitNhJoinClause(string querySourceName, NhJoinClause joinClause)
+		{
+			var expression = HqlGeneratorExpressionTreeVisitor.Visit(joinClause.FromExpression, VisitorParameters).AsExpression();
+			var alias = _hqlTree.TreeBuilder.Alias(querySourceName);
+
+			HqlTreeNode hqlJoin;
+			if (joinClause.IsInner)
+			{
+				hqlJoin = _hqlTree.TreeBuilder.Join(expression, @alias);
+			}
+			else
+			{
+				hqlJoin = _hqlTree.TreeBuilder.LeftJoin(expression, @alias);
+			}
+
+			_hqlTree.AddFromClause(hqlJoin);
+		}
+
 		public override void VisitResultOperator(ResultOperatorBase resultOperator, QueryModel queryModel, int index)
 		{
 			PreviousEvaluationType = CurrentEvaluationType;