From 4ec340c8ffe48dbc05a2f6010a4c9dae2bf3d1e9 Mon Sep 17 00:00:00 2001
From: Haled Odat <halidodat@gmail.com>
Date: Sat, 25 Mar 2023 10:23:23 +0100
Subject: [PATCH] Fix deletion of a single property object

---
 boa_engine/src/object/shape/shared_shape.rs | 24 ++++++++++++---------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/boa_engine/src/object/shape/shared_shape.rs b/boa_engine/src/object/shape/shared_shape.rs
index c4d8b919758..552b5f1ce6f 100644
--- a/boa_engine/src/object/shape/shared_shape.rs
+++ b/boa_engine/src/object/shape/shared_shape.rs
@@ -128,6 +128,15 @@ pub(crate) struct SharedShape {
 impl SharedShape {
     const DEBUG: bool = false;
 
+    fn property_table_count(&self) -> u32 {
+        if self.previous().is_some() {
+            return self.property_index() + 1;
+        }
+
+        // root has no elements
+        0
+    }
+
     #[inline]
     pub(crate) fn previous(&self) -> Option<&SharedShape> {
         self.inner.previous.as_ref()
@@ -137,7 +146,7 @@ impl SharedShape {
         let properties = self.inner.property_table.properties().borrow();
         let (key, (index, attributes)) = properties
             .get_index(self.inner.property_index as usize)
-            .expect("There should be a key in property table");
+            .expect("There should be a property");
         (key.clone(), *index, *attributes)
     }
     fn transition_type(&self) -> TransitionType {
@@ -181,18 +190,12 @@ impl SharedShape {
             (self.property_index() + 1) * 2
         };
 
-        let self_property_count = if self.previous().is_none() {
-            0
-        } else {
-            self.property_index() + 1
-        };
-
         let (property_index, property_table) =
             self.inner.property_table.add_property_deep_clone_if_needed(
                 key.property_key.clone(),
                 key.attributes,
                 slot_index,
-                self_property_count,
+                self.property_table_count(),
             );
         let new_inner_shape = Inner {
             forward_property_transitions: GcRefCell::new(FxHashMap::default()),
@@ -313,7 +316,7 @@ impl SharedShape {
             current = current_shape.previous();
         };
 
-        for (property_key, attributes) in IntoIterator::into_iter(transitions).rev() {
+        for (property_key, attributes) in transitions.into_iter().rev() {
             let transition = TransitionKey {
                 property_key,
                 attributes,
@@ -357,7 +360,7 @@ impl SharedShape {
     pub(crate) fn keys(&self) -> Vec<PropertyKey> {
         let property_table = self.inner.property_table.properties().borrow();
 
-        let property_count = (self.property_index() + 1) as usize;
+        let property_count = self.property_table_count() as usize;
 
         let mut keys: Vec<PropertyKey> = property_table
             .keys()
@@ -365,6 +368,7 @@ impl SharedShape {
             .filter(|key| matches!(key, PropertyKey::String(_)))
             .cloned()
             .collect();
+
         keys.extend(
             property_table
                 .keys()