Test case that NHibernate starts to compute the boolean value incorrect after a certain scenario

src/NHibernate.Test/NHSpecificTest/GH2529/DateTimeAddYearsMethodHqlGenerator.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.ObjectModel;
+using System.Linq.Expressions;
+using System.Reflection;
+using NHibernate.Hql.Ast;
+using NHibernate.Linq.Functions;
+using NHibernate.Linq.Visitors;
+using NHibernate.Util;
+
+namespace NHibernate.Test.NHSpecificTest.GH2529
+{
+	public class DateTimeAddYearsMethodHqlGenerator : BaseHqlGeneratorForMethod
+	{
+		public DateTimeAddYearsMethodHqlGenerator()
+		{
+			SupportedMethods = new[] {
+				ReflectHelper.GetMethodDefinition((DateTime x) => x.AddYears(0))
+			};
+		}
+
+		public override HqlTreeNode BuildHql(
+			MethodInfo method,
+			Expression targetObject,
+			ReadOnlyCollection<Expression> arguments,
+			HqlTreeBuilder treeBuilder,
+			IHqlExpressionVisitor visitor
+		)
+		{
+			return treeBuilder.MethodCall(
+				nameof(DateTime.AddYears),
+				visitor.Visit(targetObject)
+					.AsExpression(),
+				visitor.Visit(arguments[0])
+					.AsExpression()
+			);
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/GH2529/DateTimeDayOfYearPropertyHqlGenerator.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using NHibernate.Hql.Ast;
+using NHibernate.Linq.Functions;
+using NHibernate.Linq.Visitors;
+using NHibernate.Util;
+
+namespace NHibernate.Test.NHSpecificTest.GH2529
+{
+	public class DateTimeDayOfYearPropertyHqlGenerator : BaseHqlGeneratorForProperty
+	{
+		public DateTimeDayOfYearPropertyHqlGenerator()
+		{
+			SupportedProperties = new[]
+			{
+				ReflectHelper.GetProperty((DateTime x) => x.DayOfYear)
+			};
+		}
+
+		public override HqlTreeNode BuildHql(
+			MemberInfo member,
+			Expression expression,
+			HqlTreeBuilder treeBuilder,
+			IHqlExpressionVisitor visitor
+		)
+		{
+			return treeBuilder.MethodCall(
+				nameof(DateTime.DayOfYear),
+				visitor.Visit(expression)
+					.AsExpression()
+			);
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/GH2529/EnhancedLinqToHqlGeneratorsRegistry.cs

@@ -0,0 +1,13 @@
+using NHibernate.Linq.Functions;
+
+namespace NHibernate.Test.NHSpecificTest.GH2529
+{
+	public class EnhancedLinqToHqlGeneratorsRegistry : DefaultLinqToHqlGeneratorsRegistry
+	{
+		public EnhancedLinqToHqlGeneratorsRegistry()
+		{
+			this.Merge(new DateTimeDayOfYearPropertyHqlGenerator());
+			this.Merge(new DateTimeAddYearsMethodHqlGenerator());
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/GH2529/EnhancedMsSql2008Dialect.cs

@@ -0,0 +1,30 @@
+using System;
+using NHibernate.Dialect;
+using NHibernate.Dialect.Function;
+
+namespace NHibernate.Test.NHSpecificTest.GH2529
+{
+	public class EnhancedMsSql2008Dialect : MsSql2008Dialect
+	{
+		protected override void RegisterFunctions()
+		{
+			base.RegisterFunctions();
+
+			RegisterFunction(
+				nameof(DateTime.DayOfYear),
+				new SQLFunctionTemplate(
+					NHibernateUtil.Int32,
+					"datepart(dy, ?1)"
+				)
+			);
+
+			RegisterFunction(
+				nameof(DateTime.AddYears),
+				new SQLFunctionTemplate(
+					NHibernateUtil.DateTime,
+					"dateadd(year,?2,?1)"
+				)
+		   );
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/GH2529/FixtureByCode.cs

@@ -0,0 +1,172 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using NHibernate.Cfg;
+using NHibernate.Cfg.MappingSchema;
+using NHibernate.Mapping.ByCode;
+using NUnit.Framework;
+
+namespace NHibernate.Test.NHSpecificTest.GH2529
+{
+	/// <summary>
+	/// Fixture using 'by code' mappings
+	/// </summary>
+	/// <remarks>
+	/// This fixture is identical to <see cref="Fixture" /> except the <see cref="User" /> mapping is performed 
+	/// by code in the GetMappings method, and does not require the <c>Mappings.hbm.xml</c> file. Use this approach
+	/// if you prefer.
+	/// </remarks>
+	[TestFixture]
+	public class ByCodeFixture : TestCaseMappingByCode
+	{
+		protected override void Configure(Configuration configuration)
+		{
+			base.Configure(configuration);
+
+			configuration.LinqToHqlGeneratorsRegistry<EnhancedLinqToHqlGeneratorsRegistry>();
+			configuration.SetProperty(Cfg.Environment.Dialect, typeof(EnhancedMsSql2008Dialect).AssemblyQualifiedName);
+		}
+
+		protected override bool AppliesTo(Dialect.Dialect dialect)
+		{
+			return dialect is EnhancedMsSql2008Dialect;
+		}
+
+		protected override HbmMapping GetMappings()
+		{
+			var mapper = new ModelMapper();
+			mapper.Class<User>(rc =>
+			{
+				rc.Table("Users");
+				rc.Id(x => x.Id, m => m.Generator(Generators.Identity));
+				rc.Property(x => x.Birthday);
+			});
+
+			return mapper.CompileMappingForAllExplicitlyAddedEntities();
+		}
+
+		protected override void OnTearDown()
+		{
+			using (var session = OpenSession())
+			using (var transaction = session.BeginTransaction())
+			{
+				session.CreateQuery("delete from System.Object").ExecuteUpdate();
+
+				transaction.Commit();
+			}
+		}
+
+		[Test, Explicit]
+		public void List_DealsWithYearTransitionProperly()
+		{
+			// arrange
+			DateTimeOffset today = new DateTimeOffset(2001, 12, 27, 08, 00, 0, TimeSpan.Zero);
+
+			CreateUser(birthday: new DateTime(1991, 12, 31));
+			CreateUser(birthday: new DateTime(1992, 01, 01));
+
+			// act
+			IReadOnlyCollection<BirthdayListItem> result = List(
+				today
+			);
+
+			// arrange
+			Assert.That(result.Count, Is.EqualTo(2));
+			BirthdayListItem firstBirthday = result.First();
+			BirthdayListItem secondBirthday = result.Skip(1).Single();
+			Assert.That(firstBirthday.IsThisYearsBirthdayInThePastNHibernate, Is.EqualTo(firstBirthday.IsThisYearsBirthdayInThePastManual));
+			Assert.That(secondBirthday.IsThisYearsBirthdayInThePastNHibernate, Is.EqualTo(secondBirthday.IsThisYearsBirthdayInThePastManual));
+		}
+
+		[Test, Explicit]
+		public void List_WorksForTomorrow()
+		{
+			// arrange
+			DateTimeOffset today = new DateTime(2000, 05, 11, 00, 00, 0, DateTimeKind.Utc);
+			CreateUser(birthday: today.AddDays(1).DateTime);
+
+			// act
+			IReadOnlyCollection<BirthdayListItem> result = List(
+				today
+			);
+
+			// arrange
+			Assert.That(result.Count, Is.EqualTo(1));
+			BirthdayListItem firstBirthday = result.First();
+			Assert.That(firstBirthday.IsThisYearsBirthdayInThePastNHibernate, Is.EqualTo(firstBirthday.IsThisYearsBirthdayInThePastManual));
+		}
+
+		[Test]
+		public void List_Both()
+		{
+			// Running these methods individual passes the test
+			// Running them in sequence fails on List_WorksForTomorrow
+			List_DealsWithYearTransitionProperly();
+			DeleteAllUsers();
+			List_WorksForTomorrow();
+		}
+
+		private User CreateUser(
+			DateTime birthday
+		)
+		{
+			using (ISession session = OpenSession())
+			using (ITransaction transaction = session.BeginTransaction())
+			{
+				var user = new User
+				{
+					Birthday = birthday,
+				};
+
+				session.Save(user);
+				transaction.Commit();
+
+				return user;
+			}
+		}
+
+		private void DeleteAllUsers()
+		{
+			using (ISession session = OpenSession())
+			using (ITransaction transaction = session.BeginTransaction())
+			{
+				string queryString = $"DELETE {typeof(User).FullName}";
+				IQuery query = session.CreateQuery(queryString);
+				query.ExecuteUpdate();
+
+				transaction.Commit();
+			}
+		}
+
+		private IReadOnlyCollection<BirthdayListItem> List(
+			DateTimeOffset today
+		)
+		{
+			using (ISession session = OpenSession())
+			{
+				return session.Query<User>()
+					.Where(x => x.Birthday != null)
+					.Select(x => new
+					{
+						BirthdayThisYear = x.Birthday.Value.AddYears(today.Year - x.Birthday.Value.Year),
+						BirthdayNextYear = x.Birthday.Value.AddYears((today.Year - x.Birthday.Value.Year) + 1),
+						IsThisYearsBirthdayInThePast = x.Birthday.Value.AddYears(today.Year - x.Birthday.Value.Year).DayOfYear < today.DayOfYear,
+					})
+					.OrderBy(x => x.IsThisYearsBirthdayInThePast ? x.BirthdayNextYear : x.BirthdayThisYear)
+					.ToArray()
+					.Select(x => new BirthdayListItem
+					{
+						IsThisYearsBirthdayInThePastNHibernate = x.IsThisYearsBirthdayInThePast,
+						IsThisYearsBirthdayInThePastManual = x.BirthdayThisYear.DayOfYear < today.DayOfYear,
+					})
+					.ToArray();
+			}
+		}
+
+		public class BirthdayListItem
+		{
+			public bool IsThisYearsBirthdayInThePastNHibernate { get; set; }
+			public bool IsThisYearsBirthdayInThePastManual { get; set; }
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/GH2529/User.cs

@@ -0,0 +1,11 @@
+using System;
+
+namespace NHibernate.Test.NHSpecificTest.GH2529
+{
+	public class User
+	{
+		public virtual int Id { get; set; }
+
+		public virtual DateTime? Birthday { get; set; }
+	}
+}

src/NHibernate.Test/NHibernate.Test.csproj

@@ -99,4 +99,7 @@
   <ItemGroup>
     <Service Include="{82a7f48d-3b50-4b1e-b82e-3ada8210c358}" />
   </ItemGroup>
+  <ItemGroup>
+    <Folder Include="NHSpecificTest\GH0000\CustomHqlGenerators\" />
+  </ItemGroup>
 </Project>