From 413385e09e8743cb9a4867b1fabc525e5516cbd7 Mon Sep 17 00:00:00 2001
From: sayomaki <sayomayomaki@gmail.com>
Date: Fri, 8 Aug 2025 16:16:09 +0800
Subject: [PATCH 1/2] Add check to ensure valid stepper output before
 processing

---
 src/pages/playground/PlaygroundTabs.tsx | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/pages/playground/PlaygroundTabs.tsx b/src/pages/playground/PlaygroundTabs.tsx
index 95aac5c5da..fe476168c0 100644
--- a/src/pages/playground/PlaygroundTabs.tsx
+++ b/src/pages/playground/PlaygroundTabs.tsx
@@ -48,7 +48,9 @@ export const makeSubstVisualizerTabFrom = (
       editorOutput &&
       editorOutput.type === 'result' &&
       editorOutput.value instanceof Array &&
-      editorOutput.value[0] === Object(editorOutput.value[0])
+      editorOutput.value[0] === Object(editorOutput.value[0]) &&
+      // check if output is from stepper
+      "ast" in editorOutput.value[0]
     ) {
       return editorOutput.value;
     } else {

From 34d5662a0208ed16f8dae8514e757c1f57c3c1cd Mon Sep 17 00:00:00 2001
From: sayomaki <sayomayomaki@gmail.com>
Date: Fri, 8 Aug 2025 16:19:38 +0800
Subject: [PATCH 2/2] Fix formatting issue

---
 src/pages/playground/PlaygroundTabs.tsx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pages/playground/PlaygroundTabs.tsx b/src/pages/playground/PlaygroundTabs.tsx
index fe476168c0..0de861f905 100644
--- a/src/pages/playground/PlaygroundTabs.tsx
+++ b/src/pages/playground/PlaygroundTabs.tsx
@@ -50,7 +50,7 @@ export const makeSubstVisualizerTabFrom = (
       editorOutput.value instanceof Array &&
       editorOutput.value[0] === Object(editorOutput.value[0]) &&
       // check if output is from stepper
-      "ast" in editorOutput.value[0]
+      'ast' in editorOutput.value[0]
     ) {
       return editorOutput.value;
     } else {