RMLNQ-28 Add compatibility code for visiting AsQueryableResultOperato…

…r only with IQueryModelVisitor implementations that support the new reuslt operator type.
re-motion · Jan 21, 2018 · e3744a4 · e3744a4
1 parent c477aea
commit e3744a4
Show file tree

Hide file tree

Showing 3 changed files with 40 additions and 0 deletions.
diff --git a/Core/Clauses/ResultOperatorBase.cs b/Core/Clauses/ResultOperatorBase.cs
@@ -17,6 +17,7 @@
 using System;
 using System.Linq.Expressions;
 using System.Reflection;
+using Remotion.Linq.Clauses.ResultOperators;
 using Remotion.Linq.Clauses.StreamedData;
 using Remotion.Linq.Utilities;
 using Remotion.Utilities;
@@ -65,6 +66,10 @@ public void Accept (IQueryModelVisitor visitor, QueryModel queryModel, int index
       ArgumentUtility.CheckNotNull ("visitor", visitor);
       ArgumentUtility.CheckNotNull ("queryModel", queryModel);
 
+      // RMLNQ-117: This condition can be removed once the marker interface becomes obsolete. This will also invalidate the associated tests in ResultOperatorBaseTest.
+      if (this is AsQueryableResultOperator && !(visitor is AsQueryableResultOperator.ISupportedByIQueryModelVistor))
+        return;
+
       visitor.VisitResultOperator (this, queryModel, index);
     }
 

diff --git a/Core/Clauses/ResultOperators/AsQueryableResultOperator.cs b/Core/Clauses/ResultOperators/AsQueryableResultOperator.cs
@@ -35,6 +35,16 @@ namespace Remotion.Linq.Clauses.ResultOperators
   /// </example>
   public sealed class AsQueryableResultOperator : SequenceTypePreservingResultOperatorBase
   {
+    /// <summary>
+    /// A marker interface that must be implemented by the <see cref="IQueryModelVisitor "/> if the visitor supports the <see cref="AsQueryableResultOperator"/>.
+    /// </summary>
+    /// <remarks>
+    /// Note that the interface will become obsolete with v3.0.0. See also RMLNQ-117.
+    /// </remarks>
+    public interface ISupportedByIQueryModelVistor
+    {
+    }
+
     /// <summary>
     /// Initializes a new instance of the <see cref="AsQueryableResultOperator"/>.
     /// </summary>

diff --git a/UnitTests/Clauses/ResultOperatorBaseTest.cs b/UnitTests/Clauses/ResultOperatorBaseTest.cs
@@ -18,6 +18,7 @@
 using System.Linq;
 using System.Linq.Expressions;
 using NUnit.Framework;
+using Remotion.Linq.Clauses.ResultOperators;
 using Remotion.Linq.Clauses.StreamedData;
 using Remotion.Linq.Development.UnitTesting;
 using Remotion.Linq.UnitTests.Clauses.ResultOperators;
@@ -50,6 +51,30 @@ public void Accept ()
       visitorMock.AssertWasCalled (mock => mock.VisitResultOperator (_resultOperator, queryModel, 1));
     }
 
+    [Test]
+    public void Accept_AsQueryableResultOperatorSupportedByVisitor_RMLNQ_117 ()
+    {
+      var queryModel = ExpressionHelper.CreateQueryModel<Cook> ();
+      var visitorMock = MockRepository.GenerateMock<IQueryModelVisitor, AsQueryableResultOperator.ISupportedByIQueryModelVistor> ();
+      var resultOperator = new AsQueryableResultOperator ();
+
+      resultOperator.Accept (visitorMock, queryModel, 1);
+
+      visitorMock.AssertWasCalled (mock => mock.VisitResultOperator (resultOperator, queryModel, 1));
+    }
+
+    [Test]
+    public void Accept_AsQueryableResultOperatorNotSupportedByVisitor_RMLNQ_117 ()
+    {
+      var queryModel = ExpressionHelper.CreateQueryModel<Cook> ();
+      var visitorMock = MockRepository.GenerateMock<IQueryModelVisitor> ();
+      var resultOperator = new AsQueryableResultOperator ();
+
+      resultOperator.Accept (visitorMock, queryModel, 1);
+
+      visitorMock.AssertWasNotCalled (mock => mock.VisitResultOperator (resultOperator, queryModel, 1));
+    }
+
     [Test]
     public void InvokeExecuteMethod ()
     {