Fix panics

boa-dev · Sep 25, 2023 · db420ed · db420ed
1 parent 61adb25
commit db420ed
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Showing 4 changed files with 12 additions and 21 deletions.
diff --git a/boa_engine/src/builtins/map/map_iterator.rs b/boa_engine/src/builtins/map/map_iterator.rs
@@ -27,7 +27,7 @@ use boa_profiler::Profiler;
 ///  - [ECMAScript reference][spec]
 ///
 /// [spec]: https://tc39.es/ecma262/#sec-map-iterator-objects
-#[derive(Debug, Clone, Finalize, Trace)]
+#[derive(Debug, Finalize, Trace)]
 pub struct MapIterator {
     iterated_map: Option<JsObject>,
     map_next_index: usize,

diff --git a/boa_engine/src/builtins/map/ordered_map.rs b/boa_engine/src/builtins/map/ordered_map.rs
@@ -217,18 +217,13 @@ impl<V> OrderedMap<V> {
 /// Increases the lock count of the map for the lifetime of the guard. This should not be dropped until iteration has completed.
 #[derive(Debug, Trace)]
 pub(crate) struct MapLock(JsObject);
-
-impl Clone for MapLock {
-    fn clone(&self) -> Self {
-        let mut map = self.0.borrow_mut();
-        let map = map.as_map_mut().expect("MapLock does not point to a map");
-        map.lock(self.0.clone())
-    }
-}
-
 impl Finalize for MapLock {
     fn finalize(&self) {
-        let mut map = self.0.borrow_mut();
+        // Avoids panicking inside `Finalize`, with the downside of slightly increasing
+        // memory usage if the map could not be borrowed.
+        let Ok(mut map) = self.0.try_borrow_mut() else {
+            return;
+        };
         let map = map.as_map_mut().expect("MapLock does not point to a map");
         map.unlock();
     }

diff --git a/boa_engine/src/builtins/set/ordered_set.rs b/boa_engine/src/builtins/set/ordered_set.rs
@@ -173,17 +173,13 @@ impl OrderedSet {
 #[derive(Debug, Trace)]
 pub(crate) struct SetLock(JsObject);
 
-impl Clone for SetLock {
-    fn clone(&self) -> Self {
-        let mut set = self.0.borrow_mut();
-        let set = set.as_set_mut().expect("SetLock does not point to a set");
-        set.lock(self.0.clone())
-    }
-}
-
 impl Finalize for SetLock {
     fn finalize(&self) {
-        let mut set = self.0.borrow_mut();
+        // Avoids panicking inside `Finalize`, with the downside of slightly increasing
+        // memory usage if the set could not be borrowed.
+        let Ok(mut set) = self.0.try_borrow_mut() else {
+            return;
+        };
         let set = set.as_set_mut().expect("SetLock does not point to a set");
         set.unlock();
     }

diff --git a/boa_engine/src/builtins/set/set_iterator.rs b/boa_engine/src/builtins/set/set_iterator.rs
@@ -27,7 +27,7 @@ use boa_profiler::Profiler;
 ///  - [ECMAScript reference][spec]
 ///
 /// [spec]: https://tc39.es/ecma262/#sec-set-iterator-objects
-#[derive(Debug, Clone, Finalize, Trace)]
+#[derive(Debug, Finalize, Trace)]
 pub struct SetIterator {
     iterated_set: JsValue,
     next_index: usize,