GraphicDataProvider Fix: Regression for pointer referencing non-clr o…

…bjects (#12934) * Fix regression for pointer object referencing non-clr objects * Update comments * Add test Co-authored-by: Craig Long <[email protected]>
DynamoDS · Jun 7, 2022 · 80d321a · 80d321a
1 parent 911ba41
commit 80d321a
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Showing 3 changed files with 36 additions and 10 deletions.
diff --git a/src/Engine/ProtoCore/ClassTable.cs b/src/Engine/ProtoCore/ClassTable.cs
@@ -494,6 +494,16 @@ public void SetClassNodeAt(ClassNode node, int index)
             symbol.Id = index;
         }
 
+        /// <summary>
+        /// Retreive the ClassNode at the index.  
+        /// </summary>
+        /// <param name="index"></param>
+        /// <returns>ClassNode if found, else null value</returns>
+        internal ClassNode GetClassNodeAtIndex(int index)
+        {
+            return index >= 0 && index < classNodes.Count ? classNodes[index] : null;
+        }
+
         /// <summary>
         /// Find a matching class for given partial class name.
         /// </summary>

diff --git a/src/Engine/ProtoCore/Reflection/GraphicDataProvider.cs b/src/Engine/ProtoCore/Reflection/GraphicDataProvider.cs
@@ -147,21 +147,24 @@ internal List<IGraphicItem> GetGraphicItems(DSASM.StackValue svData, RuntimeCore
 
         internal object GetCLRObject(StackValue svData, RuntimeCore runtimeCore)
         {
-            if (marshaler != null)
-            {
-                return marshaler.UnMarshal(svData, null, interpreter, typeof(object));
-            }
-
             if (null == runtimeCore.DSExecutable.classTable)
                 return null;
 
-            IList<ClassNode> classNodes = runtimeCore.DSExecutable.classTable.ClassNodes;
-            if (null == classNodes || (classNodes.Count <= 0))
+            //The GetCLRObject function is typically utilized to retrieve a ClrObject from a StackValue of type pointer.
+            //There is an edge cases for pointers where the pointer references a non CLR object.  This code
+            //checks for this edge case by verifying that the requested StackValue pointer is associated with an
+            //imported library.  An example is the "Function" pointer which does not have an associated CLRObject.
+            //In that case, the return value should be null.
+            var classNode = runtimeCore.DSExecutable.classTable.GetClassNodeAtIndex(svData.metaData.type);
+            if (classNode != null  && !classNode.IsImportedClass)
+            {
                 return null;
+            }
 
-            ClassNode classnode = runtimeCore.DSExecutable.classTable.ClassNodes[svData.metaData.type];
-            if (!classnode.IsImportedClass) //TODO: look at properties to see if it contains any FFI objects.
-                return null;
+            if (marshaler != null)
+            {
+                return marshaler.UnMarshal(svData, null, interpreter, typeof(object));
+            }
 
             try
             {

diff --git a/test/DynamoCoreTests/Nodes/ListTests.cs b/test/DynamoCoreTests/Nodes/ListTests.cs
@@ -665,6 +665,19 @@ public void SortBy_SimpleTest()
 		}
 
         [Test]
+        public void SortBy_PreviewValueIsCorrectForFunction()
+        {
+            string openPath = Path.Combine(TestDirectory, @"core\list\SortBy_SimpleTest.dyn");
+            RunModel(openPath);
+
+            var preview = GetPreviewValueInString("42ac0cec-442f-4e4a-b629-1260f6db3d86");
+            Assert.AreEqual("Function()", preview);
+
+            var value = GetPreviewValue("42ac0cec-442f-4e4a-b629-1260f6db3d86");
+            Assert.Null(value);
+        }
+
+		[Test]
         public void SortByKey_SimpleTest()
         {
             string openPath = Path.Combine(TestDirectory, @"core\list\ListSortByKey.dyn");