NH-3800 and NH-3681

src/NHibernate.Test/Linq/ByMethod/GroupByTests.cs

@@ -507,14 +507,22 @@ public void ProjectingWithSubQueriesFilteredByTheAggregateKey()
 			Assert.That(result[15].FirstOrder, Is.EqualTo(10255));
 		}
 
-		[Test(Description = "NH-3681"), KnownBug("NH-3681 not yet fixed", "NHibernate.HibernateException")]
+		[Test(Description = "NH-3681")]
 		public void SelectManyGroupByAggregateProjection()
 		{
 			var result = (from o in db.Orders
-			              from ol in o.OrderLines
-			              group ol by ol.Product.ProductId
-			              into grp
-			              select new {ProductId = grp.Key, Sum = grp.Sum(x => x.UnitPrice)}
+						  from ol in o.OrderLines
+						  group ol by ol.Product.ProductId
+							  into grp
+							  select new
+							  {
+								  ProductId = grp.Key,
+								  Sum = grp.Sum(x => x.UnitPrice),
+								  Count = grp.Count(),
+								  Avg = grp.Average(x => x.UnitPrice),
+								  Min = grp.Min(x => x.UnitPrice),
+								  Max = grp.Max(x => x.UnitPrice),
+							  }
 				).ToList();
 
 			Assert.That(result.Count, Is.EqualTo(77));

src/NHibernate.Test/NHSpecificTest/NH3800/Domain.cs

@@ -0,0 +1,48 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace NHibernate.Test.NHSpecificTest.NH3800
+{
+	public class Project
+	{
+		public Project()
+		{
+			Components = new List<Component>();
+		}
+
+		public virtual Guid Id { get; set; }
+		public virtual string Name { get; set; }
+		public virtual IList<Component> Components { get; set; }
+	}
+
+	public class Component
+	{
+		public virtual Guid Id { get; set; }
+		public virtual string Name { get; set; }
+		public virtual Project Project { get; set; }
+	}
+
+	public class TimeRecord
+	{
+		public TimeRecord()
+		{
+			Components = new List<Component>();
+			Tags = new List<Tag>();
+		}
+
+		public virtual Guid Id { get; set; }
+		public virtual double TimeInHours { get; set; }
+		public virtual Project Project { get; set; }
+		public virtual IList<Component> Components { get; set; }
+		public virtual IList<Tag> Tags { get; set; }
+
+	}
+
+	public class Tag
+	{
+		public virtual Guid Id { get; set; }
+		public virtual string Name { get; set; }
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3800/Fixture.cs

@@ -0,0 +1,193 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Reflection;
+using System.Text;
+using System.Threading;
+using NHibernate.Linq;
+using NHibernate.Test.ExceptionsTest;
+using NHibernate.Test.MappingByCode;
+using NUnit.Framework;
+
+namespace NHibernate.Test.NHSpecificTest.NH3800
+{
+	[TestFixture]
+	public class Fixture : BugTestCase
+	{
+		protected override void OnSetUp()
+		{
+			var tagA = new Tag() { Name = "A" };
+			var tagB = new Tag() { Name = "B" };
+
+			var project1 = new Project { Name = "ProjectOne" };
+			var compP1_x = new Component() { Name = "PONEx", Project = project1 };
+			var compP1_y = new Component() { Name = "PONEy", Project = project1 };
+
+			var project2 = new Project { Name = "ProjectTwo" };
+			var compP2_x = new Component() { Name = "PTWOx", Project = project2 };
+			var compP2_y = new Component() { Name = "PTWOy", Project = project2 };
+
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				session.Save(tagA);
+				session.Save(tagB);
+				session.Save(project1);
+				session.Save(compP1_x);
+				session.Save(compP1_y);
+				session.Save(project2);
+				session.Save(compP2_x);
+				session.Save(compP2_y);
+
+				session.Save(new TimeRecord { TimeInHours = 1, Project = null, Components = { }, Tags = { tagA } });
+				session.Save(new TimeRecord { TimeInHours = 2, Project = null, Components = { }, Tags = { tagB } });
+
+				session.Save(new TimeRecord { TimeInHours = 3, Project = project1, Tags = { tagA, tagB } });
+				session.Save(new TimeRecord { TimeInHours = 4, Project = project1, Components = { compP1_x }, Tags = { tagB } });
+				session.Save(new TimeRecord { TimeInHours = 5, Project = project1, Components = { compP1_y }, Tags = { tagA } });
+				session.Save(new TimeRecord { TimeInHours = 6, Project = project1, Components = { compP1_x, compP1_y }, Tags = { } });
+
+				session.Save(new TimeRecord { TimeInHours = 7, Project = project2, Components = { }, Tags = { tagA, tagB } });
+				session.Save(new TimeRecord { TimeInHours = 8, Project = project2, Components = { compP2_x }, Tags = { tagB } });
+				session.Save(new TimeRecord { TimeInHours = 9, Project = project2, Components = { compP2_y }, Tags = { tagA } });
+				session.Save(new TimeRecord { TimeInHours = 10, Project = project2, Components = { compP2_x, compP2_y }, Tags = { } });
+
+				transaction.Commit();
+			}
+		}
+
+		protected override void OnTearDown()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				session.Delete("from TimeRecord");
+				session.Delete("from Component");
+				session.Delete("from Project");
+				session.Delete("from Tag");
+
+				transaction.Commit();
+			}
+		}
+
+		[Test]
+		public void ExpectedHql()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				var baseQuery = session.Query<TimeRecord>();
+
+				Assert.That(baseQuery.Sum(x => x.TimeInHours), Is.EqualTo(55));
+
+				var query = session.CreateQuery(@"
+                    select c.Id, count(t), sum(cast(t.TimeInHours as big_decimal)) 
+                    from TimeRecord t 
+                    left join t.Components as c 
+                    group by c.Id");
+
+				var results = query.List<object[]>();
+				Assert.That(results.Select(x => x[1]), Is.EquivalentTo(new[] { 4, 2, 2, 2, 2 }));
+				Assert.That(results.Select(x => x[2]), Is.EquivalentTo(new[] { 13, 10, 11, 18, 19 }));
+
+				Assert.That(results.Sum(x => (decimal?)x[2]), Is.EqualTo(71));
+
+				transaction.Rollback();
+			}
+		}
+
+		[Test]
+		public void PureLinq()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				var baseQuery = session.Query<TimeRecord>();
+				var query = from t in baseQuery
+							from c in t.Components.Select(x => (object)x.Id).DefaultIfEmpty()
+							let r = new object[] { c, t }
+							group r by r[0]
+								into g
+								select new[] { g.Key, g.Select(x => x[1]).Count(), g.Select(x => x[1]).Sum(x => (decimal?)((TimeRecord)x).TimeInHours) };
+
+				var results = query.ToList();
+				Assert.That(results.Select(x => x[1]), Is.EquivalentTo(new[] { 4, 2, 2, 2, 2 }));
+				Assert.That(results.Select(x => x[2]), Is.EquivalentTo(new[] { 13, 10, 11, 18, 19 }));
+
+				Assert.That(results.Sum(x => (decimal?)x[2]), Is.EqualTo(71));
+
+				transaction.Rollback();
+			}
+		}
+
+		[Test]
+		public void MethodGroup()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				var baseQuery = session.Query<TimeRecord>();
+				var query = baseQuery
+						.SelectMany(t => t.Components.Select(c => c.Id).DefaultIfEmpty().Select(c => new object[] { c, t }))
+						.GroupBy(g => g[0], g => (TimeRecord)g[1])
+						.Select(g => new[] { g.Key, g.Count(), g.Sum(x => (decimal?)x.TimeInHours) });
+
+				var results = query.ToList();
+				Assert.That(results.Select(x => x[1]), Is.EquivalentTo(new[] { 4, 2, 2, 2, 2 }));
+				Assert.That(results.Select(x => x[2]), Is.EquivalentTo(new[] { 13, 10, 11, 18, 19 }));
+
+				Assert.That(results.Sum(x => (decimal?)x[2]), Is.EqualTo(71));
+
+				transaction.Rollback();
+			}
+		}
+
+		[Test]
+		public void ComplexExample()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				var baseQuery = session.Query<TimeRecord>();
+
+				Assert.That(baseQuery.Sum(x => x.TimeInHours), Is.EqualTo(55));
+
+				var query = baseQuery.Select(t => new object[] { t })
+					.SelectMany(t => ((TimeRecord)t[0]).Components.Select(c => (object)c.Id).DefaultIfEmpty().Select(c => new[] { t[0], c }))
+					.SelectMany(t => ((TimeRecord)t[0]).Tags.Select(x => (object)x.Id).DefaultIfEmpty().Select(x => new[] { t[0], t[1], x }))
+					.GroupBy(j => new[] { ((TimeRecord)j[0]).Project.Id, j[1], j[2] }, j => (TimeRecord)j[0])
+					.Select(g => new object[] { g.Key, g.Count(), g.Sum(t => (decimal?)t.TimeInHours) });
+
+				var results = query.ToList();
+				Assert.That(results.Select(x => x[1]), Is.EquivalentTo(new[] { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }));
+				Assert.That(results.Select(x => x[2]), Is.EquivalentTo(new[] { 1, 2, 3, 3, 4, 5, 6, 6, 7, 7, 8, 9, 10, 10 }));
+
+				Assert.That(results.Sum(x => (decimal?)x[2]), Is.EqualTo(81));
+
+				transaction.Rollback();
+			}
+		}
+
+		[Test]
+		public void OuterJoinGroupingWithSubQueryInProjection()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				var baseQuery = session.Query<TimeRecord>();
+				var query = baseQuery
+						.SelectMany(t => t.Components.Select(c => c.Name).DefaultIfEmpty().Select(c => new object[] { c, t }))
+						.GroupBy(g => g[0], g => (TimeRecord)g[1])
+						.Select(g => new[] { g.Key, g.Count(), session.Query<Component>().Count(c => c.Name == (string)g.Key) });
+
+				var results = query.ToList();
+				Assert.That(results.Select(x => x[1]), Is.EquivalentTo(new[] { 4, 2, 2, 2, 2 }));
+				Assert.That(results.Select(x => x[2]), Is.EquivalentTo(new[] { 0, 1, 1, 1, 1 }));
+
+				transaction.Rollback();
+			}
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3800/Mappings.hbm.xml

@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
+				   namespace="NHibernate.Test.NHSpecificTest.NH3800"
+				   assembly="NHibernate.Test">
+
+  <class name="Project">
+    <id name="Id" column="ProjectId">
+      <generator class="guid.comb"/>
+    </id>
+    <property name="Name" not-null="true"/>
+    <bag name="Components"  inverse="true" lazy="true" fetch="select">
+      <key>
+        <column name="ProjectId" not-null="true" />
+      </key>
+      <one-to-many class="Component" />
+    </bag>
+  </class>
+
+  <class name="Component">
+    <id name="Id" column="ComponentId">
+      <generator class="guid.comb"/>
+    </id>
+    <property name="Name" not-null="true"/>
+    <many-to-one name="Project" column="ProjectId" class="Project" not-null="true"/>
+  </class>
+
+  <class name="TimeRecord">
+    <id name="Id" column="TimeRecordId">
+      <generator class="guid.comb"/>
+    </id>
+    <property name="TimeInHours" not-null="true"/>
+    <many-to-one name="Project" column="ProjectId" class="Project" />
+    <bag name="Components" inverse="false" lazy="true" fetch="select">
+      <key>
+        <column name="TimeRecordId" not-null="true" />
+      </key>
+      <many-to-many class="Component">
+        <column name="ComponentId" not-null="true" />
+      </many-to-many>
+    </bag>
+    <bag name="Tags"  inverse="false" lazy="true" fetch="select">
+      <key>
+        <column name="TimeRecordId" not-null="true" />
+      </key>
+      <many-to-many class="Tag">
+        <column name="TagId" not-null="true" />
+      </many-to-many>
+    </bag>
+  </class>
+
+  <class name="Tag">
+    <id name="Id" column="TagId">
+      <generator class="guid.comb"/>
+    </id>
+    <property name="Name" not-null="true"/>
+  </class>
+
+</hibernate-mapping>

src/NHibernate.Test/NHibernate.Test.csproj

@@ -1263,6 +1263,8 @@
     <Compile Include="NHSpecificTest\NH2860\SampleTest.cs" />
     <Compile Include="NHSpecificTest\NH3641\Domain.cs" />
     <Compile Include="NHSpecificTest\NH3641\TestFixture.cs" />
+    <Compile Include="NHSpecificTest\NH3800\Domain.cs" />
+    <Compile Include="NHSpecificTest\NH3800\Fixture.cs" />
     <Compile Include="NHSpecificTest\Properties\CompositePropertyRefTest.cs" />
     <Compile Include="NHSpecificTest\Properties\DynamicEntityTest.cs" />
     <Compile Include="NHSpecificTest\Properties\Model.cs" />
@@ -3147,6 +3149,9 @@
     </EmbeddedResource>
     <EmbeddedResource Include="VersionTest\Db\MsSQL\ProductWithVersionAndLazyProperty.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3754\Mappings.hbm.xml" />
+    <EmbeddedResource Include="NHSpecificTest\NH3800\Mappings.hbm.xml">
+      <SubType>Designer</SubType>
+    </EmbeddedResource>
     <EmbeddedResource Include="LazyComponentTest\Person.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3372\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3567\Mappings.hbm.xml" />

src/NHibernate/Linq/ExpressionExtensions.cs

@@ -1,4 +1,5 @@
-using System.Linq;
+using System;
+using System.Linq;
 using System.Linq.Expressions;
 using Remotion.Linq.Clauses;
 using Remotion.Linq.Clauses.Expressions;
@@ -32,5 +33,25 @@ public static bool IsGroupingKeyOf(this MemberExpression expression,GroupResultO
 
 			return query.QueryModel.ResultOperators.Contains(groupBy);
 		}
+
+		public static bool IsGroupingElementOf(this QuerySourceReferenceExpression expression, GroupResultOperator groupBy)
+		{
+			var fromClause = expression.ReferencedQuerySource as MainFromClause;
+			if (fromClause == null) return false;
+
+			var innerQuerySource = fromClause.FromExpression as QuerySourceReferenceExpression;
+			if (innerQuerySource == null) return false;
+
+			if (innerQuerySource.ReferencedQuerySource.ItemName != groupBy.ItemName
+				|| innerQuerySource.ReferencedQuerySource.ItemType != groupBy.ItemType) return false;
+
+			var innerFromClause = innerQuerySource.ReferencedQuerySource as MainFromClause;
+			if (innerFromClause == null) return false;
+
+			var query = innerFromClause.FromExpression as SubQueryExpression;
+			if (query == null) return false;
+
+			return query.QueryModel.ResultOperators.Contains(groupBy);
+		}
 	}
 }