Optimize also IdentityRemove

Author: bahusoid

src/NHibernate/Async/Collection/AbstractPersistentCollection.cs

@@ -215,27 +215,24 @@ protected virtual async Task<ICollection> GetOrphansAsync(ICollection oldElement
 		public async Task IdentityRemoveAsync(IList list, object obj, string entityName, ISessionImplementor session, CancellationToken cancellationToken)
 		{
 			cancellationToken.ThrowIfCancellationRequested();
-			if (obj != null && await (ForeignKeys.IsNotTransientSlowAsync(entityName, obj, session, cancellationToken)).ConfigureAwait(false))
-			{
-				IType idType = session.Factory.GetEntityPersister(entityName).IdentifierType;
+			if (obj == null || await (ForeignKeys.IsTransientSlowAsync(entityName, obj, session, cancellationToken)).ConfigureAwait(false))
+				return;
 
-				object idOfCurrent = await (ForeignKeys.GetEntityIdentifierIfNotUnsavedAsync(entityName, obj, session, cancellationToken)).ConfigureAwait(false);
-				List<object> toRemove = new List<object>(list.Count);
-				foreach (object current in list)
+			var persister = session.Factory.GetEntityPersister(entityName);
+			IType idType = persister.IdentifierType;
+			object idToRemove = persister.GetIdentifier(obj);
+
+			for (var index = list.Count - 1; index >= 0; index--)
+			{
+				object current = list[index];
+				if (current == null)
 				{
-					if (current == null)
-					{
-						continue;
-					}
-					object idOfOld = await (ForeignKeys.GetEntityIdentifierIfNotUnsavedAsync(entityName, current, session, cancellationToken)).ConfigureAwait(false);
-					if (idType.IsEqual(idOfCurrent, idOfOld, session.Factory))
-					{
-						toRemove.Add(current);
-					}
+					continue;
 				}
-				foreach (object ro in toRemove)
+
+				if (obj == current || idType.IsEqual(idToRemove, persister.GetIdentifier(current), session.Factory))
 				{
-					list.Remove(ro);
+					list.RemoveAt(index);
 				}
 			}
 		}

src/NHibernate/Collection/AbstractPersistentCollection.cs

@@ -756,27 +756,24 @@ protected virtual ICollection GetOrphans(ICollection oldElements, ICollection cu
 
 		public void IdentityRemove(IList list, object obj, string entityName, ISessionImplementor session)
 		{
-			if (obj != null && ForeignKeys.IsNotTransientSlow(entityName, obj, session))
-			{
-				IType idType = session.Factory.GetEntityPersister(entityName).IdentifierType;
+			if (obj == null || ForeignKeys.IsTransientSlow(entityName, obj, session))
+				return;
 
-				object idOfCurrent = ForeignKeys.GetEntityIdentifierIfNotUnsaved(entityName, obj, session);
-				List<object> toRemove = new List<object>(list.Count);
-				foreach (object current in list)
+			var persister = session.Factory.GetEntityPersister(entityName);
+			IType idType = persister.IdentifierType;
+			object idToRemove = persister.GetIdentifier(obj);
+
+			for (var index = list.Count - 1; index >= 0; index--)
+			{
+				object current = list[index];
+				if (current == null)
 				{
-					if (current == null)
-					{
-						continue;
-					}
-					object idOfOld = ForeignKeys.GetEntityIdentifierIfNotUnsaved(entityName, current, session);
-					if (idType.IsEqual(idOfCurrent, idOfOld, session.Factory))
-					{
-						toRemove.Add(current);
-					}
+					continue;
 				}
-				foreach (object ro in toRemove)
+
+				if (obj == current || idType.IsEqual(idToRemove, persister.GetIdentifier(current), session.Factory))
 				{
-					list.Remove(ro);
+					list.RemoveAt(index);
 				}
 			}
 		}