Fix OData filtering by a base class member (#2387)

src/NHibernate.Test/Async/Linq/ODataTests.cs

@@ -65,6 +65,28 @@ public async Task OrderGroupByAsync(string queryString, int expectedRows)
 			Assert.That(results, Has.Count.EqualTo(expectedRows));
 		}
 
+		private class CustomerVm : BaseCustomerVm
+		{
+		}
+
+		private class BaseCustomerVm
+		{
+			public string Id { get; set; }
+
+			public string Name { get; set; }
+		}
+
+		[TestCase("$filter=Name eq 'Maria Anders'", 1)]
+		public async Task BasePropertyFilterAsync(string queryString, int expectedRows)
+		{
+			var query = ApplyFilter(
+				session.Query<Customer>().Select(o => new CustomerVm {Name = o.ContactName, Id = o.CustomerId}),
+				queryString);
+
+			var results = await (((IQueryable<CustomerVm>) query).ToListAsync());
+			Assert.That(results, Has.Count.EqualTo(expectedRows));
+		}
+
 		private IQueryable ApplyFilter<T>(IQueryable<T> query, string queryString)
 		{
 			var context = new ODataQueryContext(CreatEdmModel(), typeof(T), null) { };
@@ -143,6 +165,8 @@ private static IEdmModel CreatEdmModel()
 			employeeModel.EntityType.Property(o => o.Title);
 			employeeModel.EntityType.HasMany(o => o.Orders);
 
+			builder.EntitySet<CustomerVm>(nameof(CustomerVm));
+
 			return builder.GetEdmModel();
 		}
 

src/NHibernate.Test/Linq/ODataTests.cs

@@ -53,6 +53,28 @@ public void OrderGroupBy(string queryString, int expectedRows)
 			Assert.That(results, Has.Count.EqualTo(expectedRows));
 		}
 
+		private class CustomerVm : BaseCustomerVm
+		{
+		}
+
+		private class BaseCustomerVm
+		{
+			public string Id { get; set; }
+
+			public string Name { get; set; }
+		}
+
+		[TestCase("$filter=Name eq 'Maria Anders'", 1)]
+		public void BasePropertyFilter(string queryString, int expectedRows)
+		{
+			var query = ApplyFilter(
+				session.Query<Customer>().Select(o => new CustomerVm {Name = o.ContactName, Id = o.CustomerId}),
+				queryString);
+
+			var results = ((IQueryable<CustomerVm>) query).ToList();
+			Assert.That(results, Has.Count.EqualTo(expectedRows));
+		}
+
 		private IQueryable ApplyFilter<T>(IQueryable<T> query, string queryString)
 		{
 			var context = new ODataQueryContext(CreatEdmModel(), typeof(T), null) { };
@@ -131,6 +153,8 @@ private static IEdmModel CreatEdmModel()
 			employeeModel.EntityType.Property(o => o.Title);
 			employeeModel.EntityType.HasMany(o => o.Orders);
 
+			builder.EntitySet<CustomerVm>(nameof(CustomerVm));
+
 			return builder.GetEdmModel();
 		}
 

src/NHibernate/Linq/NhLinqExpression.cs

@@ -87,6 +87,7 @@ public IASTNode Translate(ISessionFactoryImplementor sessionFactory, bool filter
 
 			var requiredHqlParameters = new List<NamedParameterDescriptor>();
 			var queryModel = NhRelinqQueryParser.Parse(_expression);
+			queryModel.TransformExpressions(TransparentIdentifierRemovingExpressionVisitor.ReplaceTransparentIdentifiers);
 			var visitorParameters = new VisitorParameters(sessionFactory, _constantToParameterMap, requiredHqlParameters,
 				new QuerySourceNamer(), TargetType, QueryMode);
 

src/NHibernate/Linq/Visitors/TransparentIdentifierRemovingExpressionVisitor.cs

@@ -29,6 +29,8 @@ namespace NHibernate.Linq.Visitors
 	// Copied from Relinq and added a fallback for comparing two member info by DeclaringType and Name
 	// 6.0 TODO: drop if https://github.com/OData/WebApi/issues/2108 is fixed and add a possible breaking
 	// change requiring to upgrade OData. (See https://github.com/nhibernate/nhibernate-core/pull/2322#discussion_r401215456 )
+	// Use this version in order to support expressions that were created programmatically and do not mimic what the C# compiler generates.
+	// Consider removing this if https://re-motion.atlassian.net/projects/RMLNQ/issues/RMLNQ-121 is fixed and we upgrade ReLinq.
 	/// <summary>
 	/// Replaces expression patterns of the form <c>new T { x = 1, y = 2 }.x</c> (<see cref="MemberInitExpression"/>) or 
 	/// <c>new T ( x = 1, y = 2 ).x</c> (<see cref="NewExpression"/>) to <c>1</c> (or <c>2</c> if <c>y</c> is accessed instead of <c>x</c>).