Add test case

Author: bahusoid

src/NHibernate.Test/Linq/CustomExtensionsExample.cs

@@ -1,9 +1,9 @@
+using System;
 using System.Collections.ObjectModel;
 using System.Linq;
 using System.Linq.Expressions;
 using System.Reflection;
 using System.Text.RegularExpressions;
-using NHibernate.Cfg;
 using NHibernate.DomainModel.Northwind.Entities;
 using NHibernate.Hql.Ast;
 using NHibernate.Linq.Functions;
@@ -23,6 +23,11 @@ public static bool IsLike(this string source, string pattern)
 
 			return Regex.IsMatch(source, pattern);
 		}
+
+		public static TimeSpan GetTime(this DateTime dateTime)
+		{
+			return dateTime.TimeOfDay;
+		}
 	}
 
 	public class MyLinqToHqlGeneratorsRegistry: DefaultLinqToHqlGeneratorsRegistry
@@ -32,6 +37,20 @@ public MyLinqToHqlGeneratorsRegistry():base()
 			RegisterGenerator(ReflectHelper.GetMethodDefinition(() => MyLinqExtensions.IsLike(null, null)),
 							  new IsLikeGenerator());
 			RegisterGenerator(ReflectHelper.GetMethodDefinition(() => new object().Equals(null)), new ObjectEqualsGenerator());
+			RegisterGenerator(ReflectHelper.GetMethodDefinition(() => MyLinqExtensions.GetTime(default(DateTime))), new GetTimeGenerator());
+		}
+	}
+
+	public class GetTimeGenerator : BaseHqlGeneratorForMethod
+	{
+		public GetTimeGenerator()
+		{
+			SupportedMethods = new[] { ReflectHelper.GetMethodDefinition(() => MyLinqExtensions.GetTime(default(DateTime))) };
+		}
+
+		public override HqlTreeNode BuildHql(MethodInfo method, Expression targetObject, ReadOnlyCollection<Expression> arguments, HqlTreeBuilder treeBuilder, IHqlExpressionVisitor visitor)
+		{
+			return treeBuilder.MethodCall("cast", visitor.Visit(arguments[0]).AsExpression(), treeBuilder.Ident(NHibernateUtil.TimeAsTimeSpan.Name));
 		}
 	}
 
@@ -81,6 +100,14 @@ public void CanUseObjectEquals()
 			Assert.That(users.All(c => c.NullableEnum1 == EnumStoredAsString.Medium), Is.True);
 		}
 
+		[Test(Description = "GH-2963")]
+		public void CanUseComparisonWithExtensionOnMappedProperty()
+		{
+			var time = DateTime.UtcNow.GetTime();
+			//using(new SqlLogSpy())
+			db.Users.Where(u => u.RegisteredAt.GetTime() > time).Select(u => u.Id).ToList();
+		}
+
 		[Test]
 		public void CanUseMyCustomExtension()
 		{