diff --git a/components/script/dom/bindings/cell.rs b/components/script/dom/bindings/cell.rs index fc0a845b748..f250e818412 100644 --- a/components/script/dom/bindings/cell.rs +++ b/components/script/dom/bindings/cell.rs @@ -10,7 +10,7 @@ use js::jsapi::{JSTracer}; use util::task_state; use util::task_state::{SCRIPT, IN_GC}; -use std::cell::{RefCell, Ref, RefMut}; +use std::cell::{BorrowState, RefCell, Ref, RefMut}; /// A mutable field in the DOM. /// @@ -67,7 +67,10 @@ impl DOMRefCell { /// Panics if this is called off the script thread. pub fn try_borrow<'a>(&'a self) -> Option> { debug_assert!(task_state::get().is_script()); - self.value.try_borrow() + match self.value.borrow_state() { + BorrowState::Writing => None, + _ => Some(self.value.borrow()), + } } /// Mutably borrows the wrapped value. @@ -82,7 +85,10 @@ impl DOMRefCell { /// Panics if this is called off the script thread. pub fn try_borrow_mut<'a>(&'a self) -> Option> { debug_assert!(task_state::get().is_script()); - self.value.try_borrow_mut() + match self.value.borrow_state() { + BorrowState::Unused => Some(self.value.borrow_mut()), + _ => None, + } } }