NH-3417 Unit test and fix

Author: Gunnar Liljas

src/NHibernate.Test/Linq/ProjectionsTests.cs

@@ -316,6 +316,83 @@ public void ProjectKnownTypeWithCollection2()
 			Assert.That(result[0].ExpandedElement.OrderLines, Is.EquivalentTo(result[0].ProjectedProperty0));
 		}
 
+        [Test]
+        public void ProjectNestedKnownTypeWithCollection()
+        {
+
+            var query = from o in db.Products
+                        select new ExpandedWrapper<Product, ExpandedWrapper<Supplier, IEnumerable<Product>>>
+                        {
+                            ExpandedElement = o,
+                            ProjectedProperty0 = new ExpandedWrapper<Supplier, IEnumerable<Product>>()
+                            {
+                                ExpandedElement = o.Supplier,
+                                ProjectedProperty0 = o.Supplier.Products,
+                                Description = "Products",
+                                ReferenceDescription = ""
+                            },
+                            Description = "Supplier",
+                            ReferenceDescription = "Supplier"
+                        };
+
+            var result = query.ToList();
+            Assert.That(result.Count, Is.EqualTo(77));
+            Assert.That(result[0].ExpandedElement.Supplier, Is.EqualTo(result[0].ProjectedProperty0.ExpandedElement));
+            Assert.That(result[0].ExpandedElement.Supplier.Products, Is.EquivalentTo(result[0].ProjectedProperty0.ProjectedProperty0));
+
+        }
+
+        [Test]
+        public void ProjectNestedAnonymousTypeWithCollection()
+        {
+
+            var query = from o in db.Products
+                        select new 
+                        {
+                            ExpandedElement = o,
+                            ProjectedProperty0 = new 
+                            { 
+                                ExpandedElement = o.Supplier, 
+                                ProjectedProperty0 = o.Supplier.Products, 
+                                Description = "Products", 
+                                ReferenceDescription = "" 
+                            },
+                            Description = "Supplier",
+                            ReferenceDescription = "Supplier"
+                        };
+
+            var result = query.ToList();
+            Assert.That(result.Count, Is.EqualTo(77));
+            Assert.That(result[0].ExpandedElement.Supplier, Is.EqualTo(result[0].ProjectedProperty0.ExpandedElement));
+            Assert.That(result[0].ExpandedElement.Supplier.Products, Is.EquivalentTo(result[0].ProjectedProperty0.ProjectedProperty0));
+
+        }
+
+        [Test]
+        public void ProjectNestedAnonymousTypeWithProjectedCollection()
+        {
+
+            var query = from o in db.Products
+                        select new
+                        {
+                            ExpandedElement = o,
+                            ProjectedProperty0 = new
+                            {
+                                ExpandedElement = o.Supplier,
+                                ProjectedProperty0 = o.Supplier.Products.Select(x=>new {x.Name}),
+                                Description = "Products",
+                                ReferenceDescription = ""
+                            },
+                            Description = "Supplier",
+                            ReferenceDescription = "Supplier"
+                        };
+
+            var result = query.ToList();
+            Assert.That(result.Count, Is.EqualTo(77));
+            Assert.That(result.Single(x => x.ExpandedElement.ProductId == 1).ProjectedProperty0.ProjectedProperty0.Count(), Is.EqualTo(3));
+
+        }
+
 		[Test]
 		public void CanProjectComplexDictionaryIndexer()
 		{

src/NHibernate/Linq/NestedSelects/NestedSelectDetector.cs

@@ -38,17 +38,13 @@ protected override Expression VisitSubQueryExpression(SubQueryExpression express
 
 		protected override Expression VisitMemberExpression(MemberExpression expression)
 		{
-			var querySourceReferenceExpression = expression.Expression as QuerySourceReferenceExpression;
-			if (querySourceReferenceExpression != null)
-			{
-				var memberType = expression.Member.GetPropertyOrFieldType();
+            var memberType = expression.Member.GetPropertyOrFieldType();
 
-				if (memberType != null && memberType.IsCollectionType() && IsMappedCollection(expression.Member))
-				{
-					Expressions.Add(expression);
-				}
+            if (memberType != null && memberType.IsCollectionType() && IsChainedFromQuerySourceReference(expression) && IsMappedCollection(expression.Member))
+			{
+				Expressions.Add(expression);
 			}
-
+			
 			return base.VisitMemberExpression(expression);
 		}
 
@@ -57,6 +53,20 @@ private bool IsMappedCollection(MemberInfo memberInfo)
 			var collectionRole = memberInfo.DeclaringType.FullName + "." + memberInfo.Name;
 
 			return sessionFactory.GetCollectionMetadata(collectionRole) != null;
-	}
+	    }
+
+        private bool IsChainedFromQuerySourceReference(MemberExpression expression)
+        {
+            while (expression != null)
+            {
+                if (expression.Expression is QuerySourceReferenceExpression)
+                {
+                    return true;
+                }
+                expression = expression.Expression as MemberExpression;
+            } 
+            
+           return false;
+        }
 	}
 }