NH-2611 - Allow injectable/inheritance of Linq query provider

src/NHibernate.Test/CfgTest/ConfigurationFixture.cs

@@ -4,10 +4,12 @@
 using System.Xml;
 using NHibernate.Cfg;
 using NHibernate.DomainModel;
+using NHibernate.Engine;
+using NHibernate.Linq;
 using NHibernate.Tool.hbm2ddl;
 using NHibernate.Util;
 using NUnit.Framework;
-using Environment=NHibernate.Cfg.Environment;
+using Environment = NHibernate.Cfg.Environment;
 
 namespace NHibernate.Test.CfgTest
 {
@@ -417,5 +419,52 @@ public void NH1348()
 			cfg.Configure(xtr);
 			// No exception expected
 		}
+
+		public class SampleQueryProvider : DefaultQueryProvider
+		{
+			public SampleQueryProvider(ISessionImplementor session) : base(session)
+			{
+
+			}
+		}
+
+		[Test]
+		public void NH2890Standard()
+		{
+			var cfg = new Configuration();
+			cfg.Configure("TestEnbeddedConfig.cfg.xml")
+				.LinqQueryProvider<SampleQueryProvider>()
+				.SetDefaultAssembly("NHibernate.DomainModel")
+				.SetDefaultNamespace("NHibernate.DomainModel");
+
+			using (var sessionFactory = cfg.BuildSessionFactory())
+			{
+				using (var session = sessionFactory.OpenSession())
+				{
+					var query = session.Query<NHibernate.DomainModel.A>();
+					Assert.IsInstanceOf(typeof(SampleQueryProvider), query.Provider);
+				}
+			}
+		}
+
+		[Test]
+		public void NH2890Xml()
+		{
+			var cfg = new Configuration();
+			cfg.Configure("TestEnbeddedConfig.cfg.xml")
+				.SetDefaultAssembly("NHibernate.DomainModel")
+				.SetDefaultNamespace("NHibernate.DomainModel");
+
+			using (var sessionFactory = cfg.BuildSessionFactory())
+			{
+				using (var session = sessionFactory.OpenSession())
+				{
+					var query = session.Query<NHibernate.DomainModel.A>();
+					Assert.IsInstanceOf(typeof(SampleQueryProvider), query.Provider);
+				}
+			}
+
+		}
+
 	}
 }

src/NHibernate.Test/CfgTest/Loquacious/ConfigurationFixture.cs

@@ -8,6 +8,7 @@
 using NHibernate.Driver;
 using NHibernate.Exceptions;
 using NHibernate.Hql.Ast.ANTLR;
+using NHibernate.Linq;
 using NHibernate.Type;
 using NUnit.Framework;
 
@@ -124,5 +125,26 @@ public void UseConnectionStringName()
 
 			Assert.That(cfg.Properties[Environment.ConnectionStringName], Is.EqualTo("MyName"));
 		}
+
+		[Test]
+		public void NH2890Loquacious()
+		{
+			var cfg = new Configuration();
+			cfg.Configure("TestEnbeddedConfig.cfg.xml")
+				.SetDefaultAssembly("NHibernate.DomainModel")
+				.SetDefaultNamespace("NHibernate.DomainModel")
+				.SessionFactory()
+				.ParsingLinqThrough<NHibernate.Test.CfgTest.ConfigurationFixture.SampleQueryProvider>();
+
+			using (var sessionFactory = cfg.BuildSessionFactory())
+			{
+				using (var session = sessionFactory.OpenSession())
+				{
+					var query = session.Query<NHibernate.DomainModel.A>();
+					Assert.IsInstanceOf(typeof(NHibernate.Test.CfgTest.ConfigurationFixture.SampleQueryProvider), query.Provider);
+				}
+			}
+		}
+
 	}
 }

src/NHibernate.Test/TestEnbeddedConfig.cfg.xml

@@ -7,5 +7,6 @@
 		<property name="connection.connection_string">Server=localhost;initial catalog=nhibernate;User Id=;Password=</property>
 		<property name="query.substitutions">true 1, false 0, yes 1, no 0</property>
 		<property name="dialect">NHibernate.Dialect.MsSql2000Dialect</property>
+		<property name="query.linq_provider_class">NHibernate.Test.CfgTest.ConfigurationFixture+SampleQueryProvider, NHibernate.Test</property>
 	</session-factory>
 </hibernate-configuration>

src/NHibernate/Cfg/ConfigurationExtensions.cs

@@ -3,6 +3,7 @@
 using NHibernate.Context;
 using NHibernate.Engine;
 using NHibernate.Hql;
+using NHibernate.Linq;
 using NHibernate.Linq.Functions;
 using NHibernate.Util;
 
@@ -46,6 +47,12 @@ public static Configuration HqlQueryTranslator<TQueryTranslator>(this Configurat
 			return configuration;
 		}
 
+		public static Configuration LinqQueryProvider<TQueryProvider>(this Configuration configuration) where TQueryProvider : INhQueryProvider
+		{
+			configuration.SetProperty(Environment.QueryLinqProvider, typeof(TQueryProvider).AssemblyQualifiedName);
+			return configuration;
+		}
+
 		public static Configuration LinqToHqlGeneratorsRegistry<TLinqToHqlGeneratorsRegistry>(this Configuration configuration) where TLinqToHqlGeneratorsRegistry : ILinqToHqlGeneratorsRegistry
 		{
 			configuration.SetProperty(Environment.LinqToHqlGeneratorsRegistry, typeof(TLinqToHqlGeneratorsRegistry).AssemblyQualifiedName);

src/NHibernate/Cfg/Environment.cs

@@ -141,6 +141,9 @@ public static string Version
 		// The classname of the HQL query parser factory
 		public const string QueryTranslator = "query.factory_class";
 
+		// The class name of the LINQ query provider class, implementing from <see cref="INhQueryProvider"/>
+		public const string QueryLinqProvider = "query.linq_provider_class";
+
 		public const string QueryImports = "query.imports";
 		public const string Hbm2ddlAuto = "hbm2ddl.auto";
 		public const string Hbm2ddlKeyWords = "hbm2ddl.keywords";

src/NHibernate/Cfg/Loquacious/FluentSessionFactoryConfiguration.cs

@@ -1,5 +1,6 @@
 using NHibernate.Bytecode;
 using NHibernate.Hql;
+using NHibernate.Linq;
 
 namespace NHibernate.Cfg.Loquacious
 {
@@ -53,6 +54,13 @@ public IFluentSessionFactoryConfiguration ParsingHqlThrough<TQueryTranslator>()
 			return this;
 		}
 
+		public IFluentSessionFactoryConfiguration ParsingLinqThrough<TQueryProvider>()
+			where TQueryProvider : INhQueryProvider
+		{
+			configuration.SetProperty(Environment.QueryLinqProvider, typeof(TQueryProvider).AssemblyQualifiedName);
+			return this;
+		}
+
 		public IProxyConfiguration Proxy { get; private set; }
 		public ICollectionFactoryConfiguration GeneratingCollections { get; private set; }
 		public IMappingsConfiguration Mapping { get; private set; }

src/NHibernate/Cfg/Loquacious/IFluentSessionFactoryConfiguration.cs

@@ -1,4 +1,5 @@
 using NHibernate.Hql;
+using NHibernate.Linq;
 namespace NHibernate.Cfg.Loquacious
 {
 	public interface IFluentSessionFactoryConfiguration
@@ -26,6 +27,7 @@ public interface IFluentSessionFactoryConfiguration
 		IFluentSessionFactoryConfiguration GenerateStatistics();
 		IFluentSessionFactoryConfiguration Using(EntityMode entityMode);
 		IFluentSessionFactoryConfiguration ParsingHqlThrough<TQueryTranslator>() where TQueryTranslator : IQueryTranslatorFactory;
+		IFluentSessionFactoryConfiguration ParsingLinqThrough<TQueryProvider>() where TQueryProvider : INhQueryProvider;
 
 		IProxyConfiguration Proxy { get; }
 

src/NHibernate/Cfg/Settings.cs

@@ -100,6 +100,8 @@ public Settings()
 
 		public IQueryTranslatorFactory QueryTranslatorFactory { get; internal set; }
 
+		public System.Type LinqQueryProviderType { get; internal set; }
+
 		public ISQLExceptionConverter SqlExceptionConverter { get; internal set; }
 
 		public bool IsWrapResultSetsEnabled { get; internal set; }

src/NHibernate/Cfg/SettingsFactory.cs

@@ -2,14 +2,14 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Data;
-
 using NHibernate.AdoNet;
 using NHibernate.AdoNet.Util;
 using NHibernate.Cache;
 using NHibernate.Connection;
 using NHibernate.Dialect;
 using NHibernate.Exceptions;
 using NHibernate.Hql;
+using NHibernate.Linq;
 using NHibernate.Linq.Functions;
 using NHibernate.Linq.Visitors;
 using NHibernate.Transaction;
@@ -137,6 +137,8 @@ public Settings BuildSettings(IDictionary<string, string> properties)
 
 			settings.QueryTranslatorFactory = CreateQueryTranslatorFactory(properties);
 
+			settings.LinqQueryProviderType = CreateLinqQueryProviderType(properties);
+
 			IDictionary<string, string> querySubstitutions = PropertiesHelper.ToDictionary(Environment.QuerySubstitutions,
 			                                                                               " ,=;:\n\t\r\f", properties);
 			if (log.IsInfoEnabled)
@@ -365,6 +367,21 @@ private static IQueryTranslatorFactory CreateQueryTranslatorFactory(IDictionary<
 			}
 		}
 
+		private static System.Type CreateLinqQueryProviderType(IDictionary<string, string> properties)
+		{
+			string className = PropertiesHelper.GetString(
+				Environment.QueryLinqProvider, properties, typeof(DefaultQueryProvider).FullName);
+			log.Info("Query provider: " + className);
+			try
+			{
+				return System.Type.GetType(className, true);
+			}
+			catch (Exception cnfe)
+			{
+				throw new HibernateException("could not find query provider class: " + className, cnfe);
+			}
+		}
+
 		private static ITransactionFactory CreateTransactionFactory(IDictionary<string, string> properties)
 		{
 			string className = PropertiesHelper.GetString(

src/NHibernate/Linq/DefaultQueryProvider.cs

@@ -18,7 +18,7 @@ public interface INhQueryProvider : IQueryProvider
 
 	public class DefaultQueryProvider : INhQueryProvider
 	{
-		private static readonly MethodInfo CreateQueryMethodDefinition = ReflectionHelper.GetMethodDefinition((DefaultQueryProvider p) => p.CreateQuery<object>(null));
+		private static readonly MethodInfo CreateQueryMethodDefinition = ReflectionHelper.GetMethodDefinition((INhQueryProvider p) => p.CreateQuery<object>(null));
 
 		private readonly WeakReference _session;
 
@@ -66,7 +66,7 @@ public virtual object ExecuteFuture(Expression expression)
 			return ExecuteFutureQuery(nhLinqExpression, query, nhQuery);
 		}
 
-		protected NhLinqExpression PrepareQuery(Expression expression, out IQuery query, out NhLinqExpression nhQuery)
+		protected virtual NhLinqExpression PrepareQuery(Expression expression, out IQuery query, out NhLinqExpression nhQuery)
 		{
 			var nhLinqExpression = new NhLinqExpression(expression, Session.Factory);
 
@@ -161,7 +161,7 @@ private static void SetParameters(IQuery query, IDictionary<string, Tuple<object
 			}
 		}
 
-		public void SetResultTransformerAndAdditionalCriteria(IQuery query, NhLinqExpression nhExpression, IDictionary<string, Tuple<object, IType>> parameters)
+		public virtual void SetResultTransformerAndAdditionalCriteria(IQuery query, NhLinqExpression nhExpression, IDictionary<string, Tuple<object, IType>> parameters)
 		{
 			query.SetResultTransformer(nhExpression.ExpressionToHqlTranslationResults.ResultTransformer);
 

src/NHibernate/Linq/NhQueryable.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Linq;
 using System.Linq.Expressions;
 using NHibernate.Engine;
@@ -12,7 +13,7 @@ public class NhQueryable<T> : QueryableBase<T>
     {
         // This constructor is called by our users, create a new IQueryExecutor.
         public NhQueryable(ISessionImplementor session)
-            : base(new DefaultQueryProvider(session))
+            : base(QueryProviderFactory.CreateQueryProvider(session))
         {
         }
 

src/NHibernate/Linq/QueryProviderFactory.cs

@@ -0,0 +1,25 @@
+using System;
+using NHibernate.Engine;
+
+namespace NHibernate.Linq
+{
+	static class QueryProviderFactory
+	{
+		/// <summary>
+		/// Builds a new query provider.
+		/// </summary>
+		/// <param name="session">A session.</param>
+		/// <returns>The new query provider instance.</returns>
+		public static INhQueryProvider CreateQueryProvider(ISessionImplementor session)
+		{
+			if (session.Factory.Settings.LinqQueryProviderType == null)
+			{
+				return new DefaultQueryProvider(session);
+			}
+			else
+			{
+				return Activator.CreateInstance(session.Factory.Settings.LinqQueryProviderType, session) as INhQueryProvider;
+			}
+		}
+	}
+}

src/NHibernate/NHibernate.csproj

@@ -299,6 +299,7 @@
     <Compile Include="Linq\NestedSelects\SelectClauseRewriter.cs" />
     <Compile Include="Linq\NestedSelects\ExpressionHolder.cs" />
     <Compile Include="Linq\Visitors\IQueryModelRewriterFactory.cs" />
+    <Compile Include="Linq\QueryProviderFactory.cs" />
     <Compile Include="Linq\Visitors\LeftJoinRewriter.cs" />
     <Compile Include="Linq\Functions\CompareGenerator.cs" />
     <Compile Include="Linq\ExpressionTransformers\SimplifyCompareTransformer.cs" />

src/NHibernate/nhibernate-configuration.xsd

@@ -93,6 +93,7 @@
 								<xs:enumeration value="cache.default_expiration" />
 								<xs:enumeration value="query.substitutions" />
 								<xs:enumeration value="query.factory_class" />
+								<xs:enumeration value="query.linq_provider_class" />
 								<xs:enumeration value="query.imports" />
 								<xs:enumeration value="hbm2ddl.auto" />
 								<xs:enumeration value="hbm2ddl.keywords" />