NH-3795 - Ignore compiler generated members of compiler generated classes in FindMemberExpression

Author: gerritsen

src/NHibernate.Test/NHSpecificTest/NH3795/Fixture.cs

@@ -0,0 +1,79 @@
+using System.Collections;
+using NHibernate.DomainModel;
+using NUnit.Framework;
+
+namespace NHibernate.Test.NHSpecificTest.NH3795
+{
+	/// <summary>
+	/// Tests in this class only failed when the code was build with the Roslyn compiler which is included in Visual Studio 2015
+	/// </summary>
+	[TestFixture]
+	public class Fixture : TestCase
+	{
+		protected Child childAliasField = null;
+		protected A aAliasField = null;
+		
+		protected override IList Mappings
+		{
+			get
+			{
+				return new[] { "ParentChild.hbm.xml", "ABC.hbm.xml" };
+			}
+		}
+		
+		
+		[Test]
+		public void TestAliasInQueryOver()
+		{
+			using (var s = sessions.OpenSession())
+			{
+				A rowalias = null;
+				s.QueryOver(() => aAliasField)
+					.SelectList(list => list
+						.Select(() => aAliasField.Id).WithAlias(() => rowalias.Id))
+					.List();
+			}
+		}
+		
+		[Test]
+		public void TestAliasInQueryOverWithConversion()
+		{
+			using (var s = sessions.OpenSession())
+			{
+				B rowalias = null;
+				s.QueryOver(() => aAliasField)
+					.SelectList(list => list
+						.Select(() => ((B)aAliasField).Count).WithAlias(() => rowalias.Count))
+					.List();
+			}
+		}
+		
+		[Test]
+		public void TestAliasInJoinAlias()
+		{
+			using (var s = sessions.OpenSession())
+			{
+				Child rowalias = null;
+				s.QueryOver<Parent>()
+					.JoinAlias(p => p.Child, () => childAliasField)
+					.SelectList(list => list
+						.Select(() => childAliasField.Id).WithAlias(() => rowalias.Id))
+					.List();
+			}
+		}
+		
+		[Test]
+		public void TestAliasInJoinQueryOver()
+		{
+			using (var s = sessions.OpenSession())
+			{
+				Child rowalias = null;
+				s.QueryOver<Parent>()
+					.JoinQueryOver(p => p.Child, () => childAliasField)
+					.SelectList(list => list
+						.Select(() => childAliasField.Id).WithAlias(() => rowalias.Id))
+				.List();
+			}
+		}
+	}
+}

src/NHibernate.Test/NHibernate.Test.csproj

@@ -810,6 +810,7 @@
     <Compile Include="NHSpecificTest\NH3202\Fixture.cs" />
     <Compile Include="NHSpecificTest\NH3604\Entity.cs" />
     <Compile Include="NHSpecificTest\NH3604\FixtureByCode.cs" />
+    <Compile Include="NHSpecificTest\NH3795\Fixture.cs" />
     <Compile Include="NHSpecificTest\NH646\Domain.cs" />
     <Compile Include="NHSpecificTest\NH646\Fixture.cs" />
     <Compile Include="NHSpecificTest\NH3234\Fixture.cs" />

src/NHibernate/Impl/ExpressionProcessor.cs

@@ -4,7 +4,7 @@
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
-
+using System.Runtime.CompilerServices;
 using NHibernate.Criterion;
 using NHibernate.Util;
 using Expression = System.Linq.Expressions.Expression;
@@ -290,6 +290,18 @@ public static ProjectionInfo FindMemberProjection(Expression expression)
 			return ProjectionInfo.ForProperty(FindMemberExpression(expression));
 		}
 
+		private static bool IsCompilerGeneratedMemberExpressionOfCompilerGeneratedClass(Expression expression)
+		{
+			var memberExpression = expression as MemberExpression;
+			if (memberExpression != null && memberExpression.Member.DeclaringType != null)
+			{
+				return Attribute.GetCustomAttribute(memberExpression.Member.DeclaringType, typeof(CompilerGeneratedAttribute)) != null 
+					&& memberExpression.Member.Name.StartsWith("<"); // Is there another way to check for a compiler generated member?
+			}
+
+			return false;
+		}
+
 		/// <summary>
 		/// Retrieves the name of the property from a member expression
 		/// </summary>
@@ -311,6 +323,11 @@ public static string FindMemberExpression(Expression expression)
 							return FindMemberExpression(memberExpression.Expression);
 					}
 
+					if (IsCompilerGeneratedMemberExpressionOfCompilerGeneratedClass(memberExpression.Expression))
+					{
+						return memberExpression.Member.Name;
+					}
+
 					return FindMemberExpression(memberExpression.Expression) + "." + memberExpression.Member.Name;
 				}
 				if (IsConversion(memberExpression.Expression.NodeType))