Fix foreach loops breaking in recursive methods when used with an expression iterator

- When using a foreach loop in a method marked with [RecursiveMethod] while iterating on an expression result, the expression result was not being pushed to the recursive stack. This could cause unexpected behavior/errors in some cases. Reported by GlitchyDev

Author: MerlinVR

Assets/UdonSharp/Editor/UdonSharpASTVisitor.cs

@@ -2206,6 +2206,12 @@ public override void VisitForEachStatement(ForEachStatementSyntax node)
                     throw new System.Exception("foreach loop must iterate an array type");
             }
 
+            if (visitorContext.isRecursiveMethod &&
+               ((arraySymbol.declarationType & SymbolDeclTypeFlags.Internal) != 0))
+            {
+                arraySymbol.declarationType |= SymbolDeclTypeFlags.NeedsRecursivePush;
+            }
+
             if (node.Type.IsVar)
             {
                 if (!isTransformIterator)

Assets/UdonSharp/Tests/TestScripts/FlowControl/RecursionTest.asset

@@ -17,6 +17,7 @@ MonoBehaviour:
   udonAssembly: 
   assemblyError: 
   sourceCsScript: {fileID: 11500000, guid: 41aa655b07e37a84292568dd0dc1aac5, type: 3}
+  behaviourSyncMode: 0
   behaviourIDHeapVarName: __refl_const_intnl_udonTypeID
   compileErrors: []
   hasInteractEvent: 0

Assets/UdonSharp/Tests/TestScripts/FlowControl/RecursionTest.cs

@@ -176,6 +176,18 @@ public string CombineStringsNested(int count, string a, string b)
             return string.Concat(a, CombineStringsNested(count - 1, CombineStringsNested(count - 1, b, a), CombineStringsNested(count - 1, a, b)), CombineStringsNested(count - 1, CombineStringsNested(count - 1, a, b), CombineStringsNested(count - 1, b, a)), "c");
         }
 
+        Transform[] GetChildrenTransforms(Transform parent)
+        {
+            Transform[] children = new Transform[parent.childCount];
+
+            for (int i = 0; i < children.Length; ++i)
+            {
+                children[i] = parent.GetChild(i);
+            }
+
+            return children;
+        }
+
         [RecursiveMethod]
         int CountChildren(Transform transformToCount)
         {
@@ -187,6 +199,28 @@ int CountChildren(Transform transformToCount)
             return childCount;
         }
 
+        [RecursiveMethod]
+        int CountChildrenForeachExpression(Transform transformToCount)
+        {
+            int childCount = transformToCount.childCount;
+
+            foreach (Transform child in GetChildrenTransforms(transformToCount))
+                childCount += CountChildrenForeachExpression(child);
+
+            return childCount;
+        }
+
+        [RecursiveMethod]
+        int CountChildrenForeachAccessExpression(Transform transformToCount)
+        {
+            int childCount = transformToCount.childCount;
+
+            foreach (Transform child in transformToCount.gameObject.transform)
+                childCount += CountChildrenForeachAccessExpression(child);
+
+            return childCount;
+        }
+
         int externChildCount;
 
         [RecursiveMethod]
@@ -280,6 +314,8 @@ public void ExecuteTests()
             tester.TestAssertion("Nested call recursion", CombineStringsNested(3, "a", "b") == "abaccbcccabccacccccbaccbccccccabccacccbaccbcccccabccaccccccc");
 
             tester.TestAssertion("Count children recursively foreach", CountChildren(transform) == 20);
+            tester.TestAssertion("Count children recursively foreach expression", CountChildrenForeachExpression(transform) == 20);
+            tester.TestAssertion("Count children recursively foreach access", CountChildrenForeachAccessExpression(transform) == 20);
 
             externChildCount = 0;
             CountChildrenExternalCount(transform);

Assets/UdonSharp/version.txt

@@ -1 +1 @@
-v0.19.11
+v0.20.0