NH-3505 - Check transience via unsaved id to eliminate need for hydrating entities to get version. Fixes lazy many-to-ones on versioned classes with stateless session updates.

Author: patearl

src/NHibernate.Test/NHSpecificTest/NH3505/Fixture.cs

@@ -0,0 +1,82 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using NHibernate.Criterion;
+using NHibernate.Linq;
+using NHibernate.Linq.Functions;
+using NUnit.Framework;
+
+namespace NHibernate.Test.NHSpecificTest.NH3505
+{
+	[TestFixture]
+	public class Fixture : BugTestCase
+	{
+		protected override void OnTearDown()
+		{
+			using (ISession s = sessions.OpenSession())
+			{
+				s.Delete("from Student");
+			    s.Delete("from Teacher");
+				s.Flush();
+			}
+		}
+
+		[Test]
+		public void StatelessSessionLazyUpdate()
+		{
+		    var s = OpenSession();
+		    Guid studentId;
+		    Guid teacherId;
+			try
+			{
+			    var teacher = new Teacher {Name = "Wise Man"};
+				s.Save(teacher);
+			    teacherId = teacher.Id;
+			    var student = new Student {Name = "Rebelious Teenager", Teacher = teacher};
+			    s.Save(student);
+			    studentId = student.Id;
+				s.Flush();
+			}
+			finally
+			{
+				s.Close();
+			}
+
+			var ss = Sfi.OpenStatelessSession();
+			try
+			{
+			    var trans = ss.BeginTransaction();
+                try
+                {
+                    var student = ss.Get<Student>(studentId);
+                    Assert.AreEqual(teacherId, student.Teacher.Id);
+                    Assert.AreEqual("Rebelious Teenager", student.Name);
+                    student.Name = "Young Protege";
+                    ss.Update(student);
+                    trans.Commit();
+                }
+                catch
+                {
+                    trans.Rollback();
+                    throw;
+                }
+            }
+			finally
+			{
+				ss.Close();
+			}
+
+			s = OpenSession();
+			try
+			{
+			    var student = s.Get<Student>(studentId);
+                Assert.AreEqual(teacherId, student.Teacher.Id);
+			    Assert.AreEqual("Young Protege", student.Name);
+			}
+			finally
+			{
+				s.Close();
+			}
+		}
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3505/Mappings.hbm.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="NHibernate.Test" namespace="NHibernate.Test.NHSpecificTest.NH3505">
+  <class name="Teacher" optimistic-lock="version">
+    <id name="Id">
+      <generator class="guid.comb" />
+    </id>
+    <version name="Version"/>
+    <property name="Name"/>
+  </class>
+  <class name="Student">
+    <id name="Id">
+      <generator class="guid.comb" />
+    </id>
+    <property name="Name"/>
+    <many-to-one name="Teacher"/>
+  </class>
+</hibernate-mapping>

src/NHibernate.Test/NHSpecificTest/NH3505/Student.cs

@@ -0,0 +1,12 @@
+using System;
+using System.Collections;
+
+namespace NHibernate.Test.NHSpecificTest.NH3505
+{
+	public class Student
+	{
+		public virtual Guid Id { get; set; }
+        public virtual string Name { get; set; }
+        public virtual Teacher Teacher { get; set; }
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH3505/Teacher.cs

@@ -0,0 +1,12 @@
+using System;
+using System.Collections;
+
+namespace NHibernate.Test.NHSpecificTest.NH3505
+{
+	public class Teacher
+	{
+		public virtual Guid Id { get; set; }
+        public virtual int Version { get; set; }
+        public virtual string Name { get; set; }
+	}
+}

src/NHibernate.Test/NHSpecificTest/NH392/Fixture.cs

@@ -33,6 +33,15 @@ public void UnsavedMinusOneNoNullReferenceException()
 					tran.Rollback();
 				}
 			}
-		}
+		}
+
+        protected override void OnTearDown()
+		{
+			using (ISession s = sessions.OpenSession())
+			{
+				s.Delete("from UnsavedValueMinusOne");
+				s.Flush();
+			}
+        }
 	}
 }

src/NHibernate.Test/NHibernate.Test.csproj

@@ -670,6 +670,9 @@
     <Compile Include="NHSpecificTest\BagWithLazyExtraAndFilter\Domain.cs" />
     <Compile Include="NHSpecificTest\BagWithLazyExtraAndFilter\Fixture.cs" />
     <Compile Include="Component\Basic\ComponentWithUniqueConstraintTests.cs" />
+    <Compile Include="NHSpecificTest\NH3505\Student.cs" />
+    <Compile Include="NHSpecificTest\NH3505\Teacher.cs" />
+    <Compile Include="NHSpecificTest\NH3505\Fixture.cs" />
     <Compile Include="NHSpecificTest\NH2923\Models.cs" />
     <Compile Include="NHSpecificTest\NH2923\ExtraLazyFixture.cs" />
     <Compile Include="NHSpecificTest\NH3405\Fixture.cs" />
@@ -2895,6 +2898,7 @@
     <EmbeddedResource Include="NHSpecificTest\NH1291AnonExample\Mappings.hbm.xml" />
   </ItemGroup>
   <ItemGroup>
+    <EmbeddedResource Include="NHSpecificTest\NH3505\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3428\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH3408\Mappings.hbm.xml" />
     <EmbeddedResource Include="NHSpecificTest\NH2408\Mappings.hbm.xml" />

src/NHibernate/Persister/Entity/AbstractEntityPersister.cs

@@ -3686,35 +3686,34 @@ public virtual void AfterReassociate(object entity, ISessionImplementor session)
 				return true;
 			}
 
-			// check the version unsaved-value, if appropriate
-			if (IsVersioned)
-			{
-				object version = GetVersion(entity, session.EntityMode);
-				// let this take precedence if defined, since it works for
-				// assigned identifiers
-				bool? result = entityMetamodel.VersionProperty.UnsavedValue.IsUnsaved(version);
-				if (result.HasValue)
-				{
-					return result;
-				}
-			}
-
-			// check the id unsaved-value
-			bool? result2 = entityMetamodel.IdentifierProperty.UnsavedValue.IsUnsaved(id);
-			if (result2.HasValue)
-			{
-				if (IdentifierGenerator is Assigned)
-				{
-					// if using assigned identifier, we can only make assumptions
-					// if the value is a known unsaved-value
-					if (result2.Value)
-						return true;
-				}
-				else
-				{
-					return result2;
-				}
-			}
+            // check the id unsaved-value
+            // We do this first so we don't have to hydrate the version property if the id property already gives us the info we need (NH-3505).
+            bool? result2 = entityMetamodel.IdentifierProperty.UnsavedValue.IsUnsaved(id);
+            if (result2.HasValue)
+            {
+                if (IdentifierGenerator is Assigned)
+                {
+                    // if using assigned identifier, we can only make assumptions
+                    // if the value is a known unsaved-value
+                    if (result2.Value)
+                        return true;
+                }
+                else
+                {
+                    return result2;
+                }
+            }
+
+            // check the version unsaved-value, if appropriate
+            if (IsVersioned)
+            {
+                object version = GetVersion(entity, session.EntityMode);
+                bool? result = entityMetamodel.VersionProperty.UnsavedValue.IsUnsaved(version);
+                if (result.HasValue)
+                {
+                    return result;
+                }
+            }
 
 			// check to see if it is in the second-level cache
 			if (HasCache)