Fix auto-flush for multi criteria

Fixes #865

Author: bahusoid

src/NHibernate.Test/Async/QueryTest/MultiCriteriaFixture.cs

@@ -474,5 +474,32 @@ public async Task UsingManyParametersAndQueries_DoesNotCauseParameterNameCollisi
 				}
 			}
 		}
+
+		//NH-2428 - Session.MultiCriteria and FlushMode.Auto inside transaction (GH865)
+		[Test]
+		public async Task MultiCriteriaAutoFlushAsync()
+		{
+			using (var s = OpenSession())
+			using (var tx = s.BeginTransaction())
+			{
+				s.FlushMode = FlushMode.Auto;
+				var p1 = new Item
+				{
+					Name = "Person name",
+					Id = 15
+				};
+				await (s.SaveAsync(p1));
+				await (s.FlushAsync());
+
+				await (s.DeleteAsync(p1));
+				var multi = s.CreateMultiCriteria();
+				multi.Add<int>(s.QueryOver<Item>().ToRowCountQuery());
+				var count = (int) ((IList) (await (multi.ListAsync()))[0])[0];
+				await (tx.CommitAsync());
+
+				Assert.That(count, Is.EqualTo(0), "Session wasn't auto flushed.");
+
+			}
+		}
 	}
 }

src/NHibernate.Test/QueryTest/MultiCriteriaFixture.cs

@@ -520,5 +520,32 @@ public void UsingManyParametersAndQueries_DoesNotCauseParameterNameCollisions()
 				}
 			}
 		}
+
+		//NH-2428 - Session.MultiCriteria and FlushMode.Auto inside transaction (GH865)
+		[Test]
+		public void MultiCriteriaAutoFlush()
+		{
+			using (var s = OpenSession())
+			using (var tx = s.BeginTransaction())
+			{
+				s.FlushMode = FlushMode.Auto;
+				var p1 = new Item
+				{
+					Name = "Person name",
+					Id = 15
+				};
+				s.Save(p1);
+				s.Flush();
+
+				s.Delete(p1);
+				var multi = s.CreateMultiCriteria();
+				multi.Add<int>(s.QueryOver<Item>().ToRowCountQuery());
+				var count = (int) ((IList) multi.List()[0])[0];
+				tx.Commit();
+
+				Assert.That(count, Is.EqualTo(0), "Session wasn't auto flushed.");
+
+			}
+		}
 	}
 }

src/NHibernate/Async/Impl/MultiCriteriaImpl.cs

@@ -12,6 +12,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Linq;
 using NHibernate.Cache;
 using NHibernate.Criterion;
 using NHibernate.Driver;
@@ -49,9 +50,14 @@ public partial class MultiCriteriaImpl : IMultiCriteria
 					}
 				}
 
+				var querySpaces = new HashSet<string>(loaders.SelectMany(l => l.QuerySpaces));
+				if (resultSetsCommand.HasQueries)
+				{
+					await (session.AutoFlushIfRequiredAsync(querySpaces, cancellationToken)).ConfigureAwait(false);
+				}
 				if (cacheable)
 				{
-					criteriaResults = await (ListUsingQueryCacheAsync(cancellationToken)).ConfigureAwait(false);
+					criteriaResults = await (ListUsingQueryCacheAsync(querySpaces, cancellationToken)).ConfigureAwait(false);
 				}
 				else
 				{
@@ -62,20 +68,18 @@ public partial class MultiCriteriaImpl : IMultiCriteria
 			}
 		}
 
-		private async Task<IList> ListUsingQueryCacheAsync(CancellationToken cancellationToken)
+		private async Task<IList> ListUsingQueryCacheAsync(HashSet<string> querySpaces, CancellationToken cancellationToken)
 		{
 			cancellationToken.ThrowIfCancellationRequested();
 			IQueryCache queryCache = session.Factory.GetQueryCache(cacheRegion);
 
 			ISet<FilterKey> filterKeys = FilterKey.CreateFilterKeys(session.EnabledFilters);
 
-			ISet<string> querySpaces = new HashSet<string>();
 			List<IType[]> resultTypesList = new List<IType[]>();
 			int[] maxRows = new int[loaders.Count];
 			int[] firstRows = new int[loaders.Count];
 			for (int i = 0; i < loaders.Count; i++)
 			{
-				querySpaces.UnionWith(loaders[i].QuerySpaces);
 				resultTypesList.Add(loaders[i].ResultTypes);
 				firstRows[i] = parameters[i].RowSelection.FirstRow;
 				maxRows[i] = parameters[i].RowSelection.MaxRows;

src/NHibernate/Impl/MultiCriteriaImpl.cs

@@ -2,6 +2,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Linq;
 using NHibernate.Cache;
 using NHibernate.Criterion;
 using NHibernate.Driver;
@@ -77,9 +78,14 @@ public IList List()
 					}
 				}
 
+				var querySpaces = new HashSet<string>(loaders.SelectMany(l => l.QuerySpaces));
+				if (resultSetsCommand.HasQueries)
+				{
+					session.AutoFlushIfRequired(querySpaces);
+				}
 				if (cacheable)
 				{
-					criteriaResults = ListUsingQueryCache();
+					criteriaResults = ListUsingQueryCache(querySpaces);
 				}
 				else
 				{
@@ -90,19 +96,17 @@ public IList List()
 			}
 		}
 
-		private IList ListUsingQueryCache()
+		private IList ListUsingQueryCache(HashSet<string> querySpaces)
 		{
 			IQueryCache queryCache = session.Factory.GetQueryCache(cacheRegion);
 
 			ISet<FilterKey> filterKeys = FilterKey.CreateFilterKeys(session.EnabledFilters);
 
-			ISet<string> querySpaces = new HashSet<string>();
 			List<IType[]> resultTypesList = new List<IType[]>();
 			int[] maxRows = new int[loaders.Count];
 			int[] firstRows = new int[loaders.Count];
 			for (int i = 0; i < loaders.Count; i++)
 			{
-				querySpaces.UnionWith(loaders[i].QuerySpaces);
 				resultTypesList.Add(loaders[i].ResultTypes);
 				firstRows[i] = parameters[i].RowSelection.FirstRow;
 				maxRows[i] = parameters[i].RowSelection.MaxRows;