Minor tweaks: rename composed_parent_node_ref, remove or update outdated comments...

components/layout_thread/dom_wrapper.rs

@@ -232,7 +232,7 @@ impl<'ln> TNode for ServoLayoutNode<'ln> {
     fn parent_node(&self) -> Option<Self> {
         unsafe {
             self.node
-                .parent_node_ref()
+                .composed_parent_node_ref()
                 .map(|node| self.new_with_this_lifetime(&node))
         }
     }
@@ -794,7 +794,12 @@ impl<'le> ::selectors::Element for ServoLayoutElement<'le> {
     }
 
     fn parent_element(&self) -> Option<ServoLayoutElement<'le>> {
-        unsafe { self.element.upcast().parent_node_ref().and_then(as_element) }
+        unsafe {
+            self.element
+                .upcast()
+                .composed_parent_node_ref()
+                .and_then(as_element)
+        }
     }
 
     fn parent_node_is_shadow_root(&self) -> bool {
@@ -1083,12 +1088,10 @@ impl<'ln> ThreadSafeLayoutNode for ServoThreadSafeLayoutNode<'ln> {
     }
 
     fn children(&self) -> LayoutIterator<Self::ChildrenIterator> {
-        if let Some(element) = self.node.as_element() {
-            if let Some(shadow) = element.shadow_root() {
-                return LayoutIterator(ThreadSafeLayoutNodeChildrenIterator::new(
-                    shadow.as_node().to_threadsafe(),
-                ));
-            }
+        if let Some(shadow) = self.node.as_element().and_then(|e| e.shadow_root()) {
+            return LayoutIterator(ThreadSafeLayoutNodeChildrenIterator::new(
+                shadow.as_node().to_threadsafe(),
+            ));
         }
         LayoutIterator(ThreadSafeLayoutNodeChildrenIterator::new(*self))
     }

components/script/dom/document.rs

@@ -376,7 +376,7 @@ pub struct Document {
     delayed_tasks: DomRefCell<Vec<Box<dyn TaskBox>>>,
     /// https://html.spec.whatwg.org/multipage/#completely-loaded
     completely_loaded: Cell<bool>,
-    /// List of shadow roots bound to the document tree.
+    /// Set of shadow roots connected to the document tree.
     shadow_roots: DomRefCell<HashSet<Dom<ShadowRoot>>>,
     /// Whether any of the shadow roots need the stylesheets flushed.
     shadow_roots_styles_changed: Cell<bool>,

components/script/dom/documentorshadowroot.rs

@@ -277,25 +277,20 @@ impl DocumentOrShadowRoot {
             "Removing named element {:p}: {:p} id={}",
             self, to_unregister, id
         );
-        // Limit the scope of the borrow because id_map might be borrowed again by
-        // GetElementById through the following sequence of calls
-        // reset_form_owner_for_listeners -> reset_form_owner -> GetElementById
-        {
-            let mut id_map = id_map.borrow_mut();
-            let is_empty = match id_map.get_mut(&id) {
-                None => false,
-                Some(elements) => {
-                    let position = elements
-                        .iter()
-                        .position(|element| &**element == to_unregister)
-                        .expect("This element should be in registered.");
-                    elements.remove(position);
-                    elements.is_empty()
-                },
-            };
-            if is_empty {
-                id_map.remove(&id);
-            }
+        let mut id_map = id_map.borrow_mut();
+        let is_empty = match id_map.get_mut(&id) {
+            None => false,
+            Some(elements) => {
+                let position = elements
+                    .iter()
+                    .position(|element| &**element == to_unregister)
+                    .expect("This element should be in registered.");
+                elements.remove(position);
+                elements.is_empty()
+            },
+        };
+        if is_empty {
+            id_map.remove(&id);
         }
     }
 
@@ -310,14 +305,8 @@ impl DocumentOrShadowRoot {
         debug!("Adding named element {:p}: {:p} id={}", self, element, id);
         assert!(element.upcast::<Node>().is_connected());
         assert!(!id.is_empty());
-
-        // Limit the scope of the borrow because id_map might be borrowed again by
-        // GetElementById through the following sequence of calls
-        // reset_form_owner_for_listeners -> reset_form_owner -> GetElementById
-        {
-            let mut id_map = id_map.borrow_mut();
-            let elements = id_map.entry(id.clone()).or_insert(Vec::new());
-            elements.insert_pre_order(element, &root);
-        }
+        let mut id_map = id_map.borrow_mut();
+        let elements = id_map.entry(id.clone()).or_insert(Vec::new());
+        elements.insert_pre_order(element, &root);
     }
 }

components/script/dom/element.rs

@@ -994,7 +994,7 @@ impl LayoutElementHelpers for LayoutDom<Element> {
         unsafe {
             let mut current_node = Some(self.upcast::<Node>());
             while let Some(node) = current_node {
-                current_node = node.parent_node_ref();
+                current_node = node.composed_parent_node_ref();
                 match node.downcast::<Element>().map(|el| el.unsafe_get()) {
                     Some(elem) => {
                         if let Some(attr) =

components/script/dom/node.rs

@@ -1175,7 +1175,7 @@ pub unsafe fn from_untrusted_node_address(
 pub trait LayoutNodeHelpers {
     unsafe fn type_id_for_layout(&self) -> NodeTypeId;
 
-    unsafe fn parent_node_ref(&self) -> Option<LayoutDom<Node>>;
+    unsafe fn composed_parent_node_ref(&self) -> Option<LayoutDom<Node>>;
     unsafe fn first_child_ref(&self) -> Option<LayoutDom<Node>>;
     unsafe fn last_child_ref(&self) -> Option<LayoutDom<Node>>;
     unsafe fn prev_sibling_ref(&self) -> Option<LayoutDom<Node>>;
@@ -1222,7 +1222,7 @@ impl LayoutNodeHelpers for LayoutDom<Node> {
 
     #[inline]
     #[allow(unsafe_code)]
-    unsafe fn parent_node_ref(&self) -> Option<LayoutDom<Node>> {
+    unsafe fn composed_parent_node_ref(&self) -> Option<LayoutDom<Node>> {
         let parent = (*self.unsafe_get()).parent_node.get_inner_as_layout();
         if let Some(ref parent) = parent {
             if let Some(shadow_root) = parent.downcast::<ShadowRoot>() {

components/script/dom/range.rs

@@ -10,7 +10,6 @@ use crate::dom::bindings::codegen::Bindings::RangeBinding::RangeMethods;
 use crate::dom::bindings::codegen::Bindings::RangeBinding::{self, RangeConstants};
 use crate::dom::bindings::codegen::Bindings::TextBinding::TextMethods;
 use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
-use crate::dom::bindings::codegen::InheritTypes::DocumentFragmentTypeId;
 use crate::dom::bindings::error::{Error, ErrorResult, Fallible};
 use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::inheritance::{CharacterDataTypeId, NodeTypeId};
@@ -764,11 +763,7 @@ impl RangeMethods for Range {
 
         // Step 11
         let new_offset = new_offset +
-            if node.type_id() ==
-                NodeTypeId::DocumentFragment(DocumentFragmentTypeId::DocumentFragment) ||
-                node.type_id() ==
-                    NodeTypeId::DocumentFragment(DocumentFragmentTypeId::ShadowRoot)
-            {
+            if let NodeTypeId::DocumentFragment(_) = node.type_id() {
                 node.len()
             } else {
                 1