From 6523a49fb7cf75e1ce402228ceaf7fe4d026c243 Mon Sep 17 00:00:00 2001
From: NetterSilver <133535268+Silvertree2010@users.noreply.github.com>
Date: Sun, 25 Oct 2026 09:16:09 +0000
Subject: [PATCH] Reject invalid layout index in master.deleteLayout and
 renameLayout

Found while testing crates/engine/src/cmd/design.rs:1353 (layout_target), used by delete_layout at :1368 and rename_layout at :1356

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
---
 crates/engine/src/cmd/design.rs | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/crates/engine/src/cmd/design.rs b/crates/engine/src/cmd/design.rs
index 08c5398c..f104526c 100644
--- a/crates/engine/src/cmd/design.rs
+++ b/crates/engine/src/cmd/design.rs
@@ -1344,17 +1344,17 @@ fn insert_layout(s: &mut Session, p: &Value) -> Result<Value> {
     })
 }
 
-fn layout_target(s: &Session, p: &Value) -> Result<(usize, usize)> {
+fn layout_target(s: &Session, p: &Value, cmd: &str) -> Result<(usize, usize)> {
     let st = s.doc()?;
     let (m, l) = match st.selection.target {
         Target::Layout { master, layout } => (master, layout),
         _ => (master_index(&st.doc, &st.selection), 0),
     };
-    Ok((usize_param(p, "master").unwrap_or(m), usize_param(p, "layout").unwrap_or(l)))
+    Ok((opt_usize_param(p, "master", cmd)?.unwrap_or(m), opt_usize_param(p, "layout", cmd)?.unwrap_or(l)))
 }
 
 fn rename_layout(s: &mut Session, p: &Value) -> Result<Value> {
-    let (mi, li) = layout_target(s, p)?;
+    let (mi, li) = layout_target(s, p, "master.renameLayout")?;
     let name = str_param(p, "name").ok_or_else(|| bad("master.renameLayout", "missing `name`"))?.to_string();
     s.edit(|doc, _| {
         let l =
@@ -1366,7 +1366,7 @@ fn rename_layout(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn delete_layout(s: &mut Session, p: &Value) -> Result<Value> {
-    let (mi, li) = layout_target(s, p)?;
+    let (mi, li) = layout_target(s, p, "master.deleteLayout")?;
     s.edit(|doc, sel| {
         let id = doc.masters.get(mi).and_then(|m| m.layouts.get(li)).map(|l| l.id).ok_or_else(|| bad("master.deleteLayout", "no such layout"))?;
         if doc.slides.iter().any(|x| x.layout == id) {
@@ -1619,6 +1619,25 @@ mod tests {
         }
     }
 
+    #[test]
+    fn layout_commands_reject_invalid_index() {
+        let mut s = Session::with_new();
+        s.execute("master.insertLayout", &json!({})).unwrap();
+        let count = |s: &Session| s.doc().unwrap().doc.masters.iter().map(|m| m.layouts.len()).sum::<usize>();
+        let names = |s: &Session| s.doc().unwrap().doc.masters.iter().flat_map(|m| m.layouts.iter().map(|l| l.name.clone())).collect::<Vec<_>>();
+        let n = count(&s);
+        let before = names(&s);
+        for bad in [json!(-1), json!(1.5)] {
+            assert!(s.execute("master.deleteLayout", &json!({"layout": bad})).is_err());
+            assert!(s.execute("master.deleteLayout", &json!({"master": bad})).is_err());
+            assert!(s.execute("master.renameLayout", &json!({"layout": bad, "name": "x"})).is_err());
+            assert_eq!(count(&s), n);
+            assert_eq!(names(&s), before);
+        }
+        s.execute("master.deleteLayout", &json!({})).unwrap();
+        assert_eq!(count(&s), n - 1);
+    }
+
     #[test]
     fn civil_dates() {
         assert_eq!(super::civil(0), (1970, 1, 1));