ISession.IsDirty() should not throw exception on new ManyToOne object in session

Author: bahusoid

src/NHibernate/Async/Type/ManyToOneType.cs

@@ -135,37 +135,49 @@ private Task<object> AssembleIdAsync(object oid, ISessionImplementor session, Ca
 			}
 		}
 
-		public override async Task<bool> IsDirtyAsync(object old, object current, ISessionImplementor session, CancellationToken cancellationToken)
+		public override Task<bool> IsDirtyAsync(object old, object current, ISessionImplementor session, CancellationToken cancellationToken)
 		{
-			cancellationToken.ThrowIfCancellationRequested();
-			if (IsSame(old, current))
+			if (cancellationToken.IsCancellationRequested)
 			{
-				return false;
+				return Task.FromCanceled<bool>(cancellationToken);
 			}
+			return IsDirtyManyToOneAsync(old, current, null, session, cancellationToken);
+		}
 
-			object oldid = await (GetIdentifierAsync(old, session, cancellationToken)).ConfigureAwait(false);
-			object newid = await (GetIdentifierAsync(current, session, cancellationToken)).ConfigureAwait(false);
-			return await (GetIdentifierType(session).IsDirtyAsync(oldid, newid, session, cancellationToken)).ConfigureAwait(false);
+		public override Task<bool> IsDirtyAsync(object old, object current, bool[] checkable, ISessionImplementor session, CancellationToken cancellationToken)
+		{
+			if (cancellationToken.IsCancellationRequested)
+			{
+				return Task.FromCanceled<bool>(cancellationToken);
+			}
+			return IsDirtyManyToOneAsync(old, current, IsAlwaysDirtyChecked ? null : checkable, session, cancellationToken);
 		}
 
-		public override async Task<bool> IsDirtyAsync(object old, object current, bool[] checkable, ISessionImplementor session, CancellationToken cancellationToken)
+		private async Task<bool> IsDirtyManyToOneAsync(object old, object current, bool[] checkable, ISessionImplementor session, CancellationToken cancellationToken)
 		{
 			cancellationToken.ThrowIfCancellationRequested();
-			if (IsAlwaysDirtyChecked)
+			if (IsSame(old, current))
+			{
+				return false;
+			}
+
+			if (old == null || current == null)
 			{
-				return await (IsDirtyAsync(old, current, session, cancellationToken)).ConfigureAwait(false);
+				return true;
 			}
-			else
+			
+			if (await (ForeignKeys.IsTransientFastAsync(GetAssociatedEntityName(), current, session, cancellationToken)).ConfigureAwait(false) == true)
 			{
-				if (IsSame(old, current))
-				{
-					return false;
-				}
-
-				object oldid = await (GetIdentifierAsync(old, session, cancellationToken)).ConfigureAwait(false);
-				object newid = await (GetIdentifierAsync(current, session, cancellationToken)).ConfigureAwait(false);
-				return await (GetIdentifierType(session).IsDirtyAsync(oldid, newid, checkable, session, cancellationToken)).ConfigureAwait(false);
+				return true;
 			}
+
+			object oldid = await (GetIdentifierAsync(old, session, cancellationToken)).ConfigureAwait(false);
+			object newid = await (GetIdentifierAsync(current, session, cancellationToken)).ConfigureAwait(false);
+			IType identifierType = GetIdentifierType(session);
+
+			return checkable == null
+				? await (identifierType.IsDirtyAsync(oldid, newid, session, cancellationToken)).ConfigureAwait(false)
+				: await (identifierType.IsDirtyAsync(old, current, checkable, session, cancellationToken)).ConfigureAwait(false);
 		}
 	}
 }

src/NHibernate/Type/ManyToOneType.cs

@@ -181,35 +181,15 @@ public override bool IsAlwaysDirtyChecked
 
 		public override bool IsDirty(object old, object current, ISessionImplementor session)
 		{
-			if (IsSame(old, current))
-			{
-				return false;
-			}
-
-			object oldid = GetIdentifier(old, session);
-			object newid = GetIdentifier(current, session);
-			return GetIdentifierType(session).IsDirty(oldid, newid, session);
+			return IsDirtyManyToOne(old, current, null, session);
 		}
 
 		public override bool IsDirty(object old, object current, bool[] checkable, ISessionImplementor session)
 		{
-			if (IsAlwaysDirtyChecked)
-			{
-				return IsDirty(old, current, session);
-			}
-			else
-			{
-				if (IsSame(old, current))
-				{
-					return false;
-				}
-
-				object oldid = GetIdentifier(old, session);
-				object newid = GetIdentifier(current, session);
-				return GetIdentifierType(session).IsDirty(oldid, newid, checkable, session);
-			}
+			return IsDirtyManyToOne(old, current, IsAlwaysDirtyChecked ? null : checkable, session);
 		}
 
+
 		public override bool IsNullable
 		{
 			get { return ignoreNotFound; }
@@ -224,5 +204,31 @@ public override bool[] ToColumnNullness(object value, IMapping mapping)
 			}
 			return result;
 		}
+
+		private bool IsDirtyManyToOne(object old, object current, bool[] checkable, ISessionImplementor session)
+		{
+			if (IsSame(old, current))
+			{
+				return false;
+			}
+
+			if (old == null || current == null)
+			{
+				return true;
+			}
+
+			if (ForeignKeys.IsTransientFast(GetAssociatedEntityName(), current, session) == true)
+			{
+				return true;
+			}
+
+			object oldid = GetIdentifier(old, session);
+			object newid = GetIdentifier(current, session);
+			IType identifierType = GetIdentifierType(session);
+
+			return checkable == null
+				? identifierType.IsDirty(oldid, newid, session)
+				: identifierType.IsDirty(old, current, checkable, session);
+		}
 	}
 }