Fix rooting in script

2 files changed, 21 insertions, 14 deletions

diff --git a/components/script/dom/bindings/js.rs b/components/script/dom/bindings/js.rs
index a4f21a2a43d..e5e9561a092 100644
--- a/components/script/dom/bindings/js.rs
+++ b/components/script/dom/bindings/js.rs
@@ -270,6 +270,12 @@ impl<T: Reflectable> MutNullableHeap<JS<T>> {
     pub unsafe fn get_inner_as_layout(&self) -> Option<LayoutJS<T>> {
         self.ptr.get().map(|js| js.to_layout())
     }
+
+    /// Get a rooted value out of this object
+    // FIXME(#6684)
+    pub fn get_rooted(&self) -> Option<Root<T>> {
+        self.get().map(|o| o.root())
+    }
 }
 
 impl<T: HeapGCValue+Copy> Default for MutNullableHeap<T> {
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index d7432c570b0..cdcc0b844af 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -328,14 +328,14 @@ impl<'a> PrivateNodeHelpers for &'a Node {
         match before {
             Some(ref before) => {
                 assert!(before.parent_node.get().map(Root::from_rooted).r() == Some(self));
-                match before.prev_sibling.get() {
+                let prev_sibling = before.prev_sibling.get_rooted();
+                match prev_sibling {
                     None => {
                         assert!(Some(*before) == self.first_child.get().map(Root::from_rooted).r());
                         self.first_child.set(Some(JS::from_ref(new_child)));
                     },
                     Some(ref prev_sibling) => {
-                        let prev_sibling = prev_sibling.root();
-                        prev_sibling.r().next_sibling.set(Some(JS::from_ref(new_child)));
+                        prev_sibling.next_sibling.set(Some(JS::from_ref(new_child)));
                         new_child.prev_sibling.set(Some(JS::from_ref(prev_sibling.r())));
                     },
                 }
@@ -343,11 +343,11 @@ impl<'a> PrivateNodeHelpers for &'a Node {
                 new_child.next_sibling.set(Some(JS::from_ref(before)));
             },
             None => {
-                match self.last_child.get() {
+                let last_child = self.last_child.get_rooted();
+                match last_child {
                     None => self.first_child.set(Some(JS::from_ref(new_child))),
                     Some(ref last_child) => {
-                        let last_child = last_child.root();
-                        assert!(last_child.r().next_sibling.get().is_none());
+                        assert!(last_child.next_sibling.get().is_none());
                         last_child.r().next_sibling.set(Some(JS::from_ref(new_child)));
                         new_child.prev_sibling.set(Some(JS::from_rooted(&last_child)));
                     }
@@ -365,22 +365,22 @@ impl<'a> PrivateNodeHelpers for &'a Node {
     /// Fails unless `child` is a child of this node.
     fn remove_child(self, child: &Node) {
         assert!(child.parent_node.get().map(Root::from_rooted).r() == Some(self));
-
-        match child.prev_sibling.get() {
+        let prev_sibling = child.prev_sibling.get_rooted();
+        match prev_sibling {
             None => {
                 self.first_child.set(child.next_sibling.get());
             }
             Some(ref prev_sibling) => {
-                prev_sibling.root().r().next_sibling.set(child.next_sibling.get());
+                prev_sibling.next_sibling.set(child.next_sibling.get());
             }
         }
-
-        match child.next_sibling.get() {
+        let next_sibling = child.next_sibling.get_rooted();
+        match next_sibling {
             None => {
                 self.last_child.set(child.prev_sibling.get());
             }
             Some(ref next_sibling) => {
-                next_sibling.root().r().prev_sibling.set(child.prev_sibling.get());
+                next_sibling.prev_sibling.set(child.prev_sibling.get());
             }
         }
 
@@ -1476,9 +1476,10 @@ impl Node {
     // https://dom.spec.whatwg.org/#concept-node-adopt
     pub fn adopt(node: &Node, document: &Document) {
         // Step 1.
-        match node.parent_node.get() {
+        let parent_node = node.parent_node.get_rooted();
+        match parent_node {
             Some(ref parent) => {
-                Node::remove(node, parent.root().r(), SuppressObserver::Unsuppressed);
+                Node::remove(node, parent, SuppressObserver::Unsuppressed);
             }
             None => (),
         }