NH-3609 - Fix using Projections.Conditional inside of Projections.Count

src/NHibernate.Test/NHSpecificTest/NH3609/Entity.cs

@@ -0,0 +1,10 @@
+using System;
+
+namespace NHibernate.Test.NHSpecificTest.NH3609
+{
+	class Entity
+	{
+		public virtual Guid Id { get; set; }
+		public virtual string Name { get; set; }
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3609/Fixture.cs

@@ -0,0 +1,82 @@
+using System.Linq;
+using NHibernate.Criterion;
+using NHibernate.Linq;
+using NHibernate.Transform;
+using NUnit.Framework;
+
+namespace NHibernate.Test.NHSpecificTest.NH3609
+{
+	[TestFixture]
+	public class Fixture : BugTestCase
+	{
+		protected override void OnSetUp()
+		{
+			using (ISession session = OpenSession())
+			using (ITransaction transaction = session.BeginTransaction())
+			{
+				var e1 = new Entity {Name = "Bob"};
+				session.Save(e1);
+
+				var e2 = new Entity {Name = "Sally"};
+				session.Save(e2);
+
+				session.Flush();
+				transaction.Commit();
+			}
+		}
+
+		protected override void OnTearDown()
+		{
+			using (ISession session = OpenSession())
+			using (ITransaction transaction = session.BeginTransaction())
+			{
+				session.Delete("from System.Object");
+
+				session.Flush();
+				transaction.Commit();
+			}
+		}
+
+		[Test]
+		public void CountWithConditionalDoesNotThrow()
+		{
+			using (ISession session = OpenSession())
+			using (session.BeginTransaction())
+			{
+			    MappingEntity mappingEntity = null;
+			    Assert.DoesNotThrow(() =>
+			        session.QueryOver<Entity>().SelectList(
+			            builder =>
+			                builder.Select(Projections.Count(Projections.Conditional(
+			                    Restrictions.Eq(Projections.Property<Entity>(x => x.Name), "FOO"),
+			                    Projections.Constant("", NHibernateUtil.String),
+                                Projections.Constant(null, NHibernateUtil.String))).WithAlias(() => mappingEntity.Count))
+			            )
+			            .TransformUsing(Transformers.AliasToBean<MappingEntity>()).List<MappingEntity>()
+			        );
+			}
+		}
+
+	    [Test]
+	    public void GroupByClauseHasParameterSet()
+	    {
+            using (ISession session = OpenSession())
+			using (session.BeginTransaction())
+			{
+			    MappingEntity mappingEntity = null;
+			    Assert.DoesNotThrow(() =>
+			        session.QueryOver<Entity>().SelectList(
+			            builder =>
+			                builder.Select(Projections.GroupProperty(
+			                    Projections.Conditional(
+			                        Restrictions.Eq(Projections.Property<Entity>(x => x.Name), ""),
+			                        Projections.Constant(1), Projections.Constant(2)))
+			                    .WithAlias(() => mappingEntity.Count))
+			            )
+			            .TransformUsing(Transformers.AliasToBean<MappingEntity>()).List<MappingEntity>()
+			        );
+			}
+
+	    }
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3609/MappingEntity.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace NHibernate.Test.NHSpecificTest.NH3609
+{
+	class MappingEntity
+	{
+		public virtual int Count { get; set; }
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3609/Mappings.hbm.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="NHibernate.Test" namespace="NHibernate.Test.NHSpecificTest.NH3609">
+
+	<class name="Entity">
+		<id name="Id" generator="guid.comb" />
+		<property name="Name" />
+	</class>
+
+</hibernate-mapping>

src/NHibernate.Test/NHibernate.Test.csproj

@@ -683,6 +683,9 @@
     <Compile Include="NHSpecificTest\BagWithLazyExtraAndFilter\Domain.cs" />
     <Compile Include="NHSpecificTest\BagWithLazyExtraAndFilter\Fixture.cs" />
     <Compile Include="Component\Basic\ComponentWithUniqueConstraintTests.cs" />
+    <Compile Include="NHSpecificTest\NH3609\MappingEntity.cs" />
+    <Compile Include="NHSpecificTest\NH3609\Entity.cs" />
+    <Compile Include="NHSpecificTest\NH3609\Fixture.cs" />
     <Compile Include="NHSpecificTest\NH1082\SynchronizationThatThrowsExceptionAtBeforeTransactionCompletion.cs" />
     <Compile Include="NHSpecificTest\NH2756\Fixture.cs" />
     <Compile Include="NHSpecificTest\NH2756\Model.cs" />
@@ -3014,6 +3017,7 @@
     <EmbeddedResource Include="NHSpecificTest\NH1291AnonExample\Mappings.hbm.xml" />
   </ItemGroup>
   <ItemGroup>
+    <EmbeddedResource Include="NHSpecificTest\NH3609\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3590\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3377\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH2865\Mappings.hbm.xml" />

src/NHibernate/Criterion/CountProjection.cs

@@ -35,19 +35,18 @@ public override SqlString ToSqlString(ICriteria criteria, int position, ICriteri
 			{
 				buf.Add("distinct ");
 			}
-		    string column;
             if(projection!=null)
             {
-                column =
+                buf.Add(
                     SqlStringHelper.RemoveAsAliasesFromSql(projection.ToSqlString(criteria, position, criteriaQuery,
-                                                                               enabledFilters)).ToString();
+                        enabledFilters)));
             }
             else
             {
-                column = criteriaQuery.GetColumn(criteria, propertyName);
+                buf.Add(criteriaQuery.GetColumn(criteria, propertyName));
             }
 
-		    buf.Add(column).Add(") as y").Add(position.ToString()).Add("_");
+		    buf.Add(") as y").Add(position.ToString()).Add("_");
 			return buf.ToSqlString();
 		}
 

src/NHibernate/Loader/AbstractEntityJoinWalker.cs

@@ -43,15 +43,15 @@ protected void InitProjection(SqlString projectionString, SqlString whereString,
 		{
 			WalkEntityTree(persister, Alias);
 			Persisters = new ILoadable[0];
-			InitStatementString(projectionString, whereString, orderByString, groupByString.ToString(), havingString, lockMode);
+			InitStatementString(projectionString, whereString, orderByString, groupByString, havingString, lockMode);
 		}
 
 		private void InitStatementString(SqlString condition, SqlString orderBy, LockMode lockMode)
 		{
-			InitStatementString(null, condition, orderBy, string.Empty, null, lockMode);
+			InitStatementString(null, condition, orderBy, null, null, lockMode);
 		}
 
-		private void InitStatementString(SqlString projection,SqlString condition, SqlString orderBy, string groupBy, SqlString having, LockMode lockMode)
+		private void InitStatementString(SqlString projection,SqlString condition, SqlString orderBy, SqlString groupBy, SqlString having, LockMode lockMode)
 		{
 			int joins = CountEntityPersisters(associations);
 			Suffixes = BasicLoader.GenerateSuffixes(joins + 1);

src/NHibernate/SqlCommand/SqlSelectBuilder.cs

@@ -18,7 +18,7 @@ public class SqlSelectBuilder : SqlBaseBuilder, ISqlStringBuilder
 		private SqlString whereClause;
 		private SqlString outerJoinsAfterWhere;
 		private SqlString orderByClause;
-		private string groupByClause;
+		private SqlString groupByClause;
 		private SqlString havingClause;
 		private LockMode lockMode;
 		private string comment;
@@ -83,7 +83,7 @@ public SqlSelectBuilder SetOrderByClause(SqlString orderByClause)
 		/// </summary>
 		/// <param name="groupByClause">The groupByClause to set</param>
 		/// <returns>The SqlSelectBuilder</returns>
-		public SqlSelectBuilder SetGroupByClause(string groupByClause)
+		public SqlSelectBuilder SetGroupByClause(SqlString groupByClause)
 		{
 			this.groupByClause = groupByClause;
 			return this;
@@ -247,7 +247,7 @@ public SqlString ToSqlString()
 				}
 			}
 
-			if (StringHelper.IsNotEmpty(groupByClause))
+			if (SqlStringHelper.IsNotEmpty(groupByClause))
 			{
 				sqlBuilder.Add(" GROUP BY ")
 					.Add(groupByClause);