Properly propagate changes when range or trees are mutated

components/script/dom/bindings/codegen/Bindings.conf

@@ -18,6 +18,10 @@ DOMInterfaces = {
     'outerObjectHook': 'Some(bindings::utils::outerize_global)',
 },
 
+'Range': {
+	'weakReferenceable': True,
+},
+
 #FIXME(jdm): This should be 'register': False, but then we don't generate enum types
 'TestBinding': {},
 

components/script/dom/bindings/weakref.rs

@@ -19,7 +19,9 @@ use js::jsapi::{JSTracer, JS_GetReservedSlot, JS_SetReservedSlot};
 use js::jsval::PrivateValue;
 use libc::c_void;
 use std::cell::{Cell, UnsafeCell};
+use std::iter::Iterator;
 use std::mem;
+use std::ops::{Deref, DerefMut, Drop};
 use util::mem::HeapSizeOf;
 
 /// The index of the slot wherein a pointer to the weak holder cell is
@@ -113,6 +115,25 @@ impl<T: WeakReferenceable> HeapSizeOf for WeakRef<T> {
     }
 }
 
+impl<T: WeakReferenceable> PartialEq for WeakRef<T> {
+   fn eq(&self, other: &Self) -> bool {
+        unsafe {
+            (**self.ptr).value.get() == (**other.ptr).value.get()
+        }
+    }
+}
+
+impl<T: WeakReferenceable> PartialEq<T> for WeakRef<T> {
+    fn eq(&self, other: &T) -> bool {
+        unsafe {
+            match (**self.ptr).value.get() {
+                Some(ptr) => *ptr == other,
+                None => false,
+            }
+        }
+    }
+}
+
 no_jsmanaged_fields!(WeakRef<T: WeakReferenceable>);
 
 impl<T: WeakReferenceable> Drop for WeakRef<T> {
@@ -182,3 +203,81 @@ impl<T: WeakReferenceable> JSTraceable for MutableWeakRef<T> {
         }
     }
 }
+
+/// A vector of weak references. On tracing, the vector retains
+/// only references which still point to live objects.
+#[allow_unrooted_interior]
+#[derive(HeapSizeOf)]
+pub struct WeakRefVec<T: WeakReferenceable> {
+    vec: Vec<WeakRef<T>>,
+}
+
+impl<T: WeakReferenceable> WeakRefVec<T> {
+    /// Create a new vector of weak references.
+    pub fn new() -> Self {
+        WeakRefVec { vec: vec![] }
+    }
+
+    /// Calls a function on each reference which still points to a
+    /// live object. The order of the references isn't preserved.
+    pub fn update<F: FnMut(WeakRefEntry<T>)>(&mut self, mut f: F) {
+        let mut i = 0;
+        while i < self.vec.len() {
+            if self.vec[i].is_alive() {
+                f(WeakRefEntry { vec: self, index: &mut i });
+            } else {
+                self.vec.swap_remove(i);
+            }
+        }
+    }
+
+    /// Clears the vector of its dead references.
+    pub fn retain_alive(&mut self) {
+        self.update(|_| ());
+    }
+}
+
+impl<T: WeakReferenceable> Deref for WeakRefVec<T> {
+    type Target = Vec<WeakRef<T>>;
+
+    fn deref(&self) -> &Vec<WeakRef<T>> {
+        &self.vec
+    }
+}
+
+impl<T: WeakReferenceable> DerefMut for WeakRefVec<T> {
+    fn deref_mut(&mut self) -> &mut Vec<WeakRef<T>> {
+        &mut self.vec
+    }
+}
+
+/// An entry of a vector of weak references. Passed to the closure
+/// given to `WeakRefVec::update`.
+#[allow_unrooted_interior]
+pub struct WeakRefEntry<'a, T: WeakReferenceable + 'a> {
+    vec: &'a mut WeakRefVec<T>,
+    index: &'a mut usize,
+}
+
+impl<'a, T: WeakReferenceable + 'a> WeakRefEntry<'a, T> {
+    /// Remove the entry from the underlying vector of weak references.
+    pub fn remove(self) -> WeakRef<T> {
+        let ref_ = self.vec.swap_remove(*self.index);
+        mem::forget(self);
+        ref_
+    }
+}
+
+impl<'a, T: WeakReferenceable + 'a> Deref for WeakRefEntry<'a, T> {
+    type Target = WeakRef<T>;
+
+    fn deref(&self) -> &WeakRef<T> {
+        &self.vec[*self.index]
+    }
+}
+
+impl<'a, T: WeakReferenceable + 'a> Drop for WeakRefEntry<'a, T> {
+    fn drop(&mut self) {
+        *self.index += 1;
+    }
+}

components/script/dom/characterdata.rs

@@ -77,13 +77,17 @@ impl CharacterDataMethods for CharacterData {
 
     // https://dom.spec.whatwg.org/#dom-characterdata-data
     fn SetData(&self, data: DOMString) {
+        let old_length = self.Length();
+        let new_length = data.utf16_units().count() as u32;
         *self.data.borrow_mut() = data;
         self.content_changed();
+        let node = self.upcast::<Node>();
+        node.ranges().replace_code_units(node, 0, old_length, new_length);
     }
 
     // https://dom.spec.whatwg.org/#dom-characterdata-length
     fn Length(&self) -> u32 {
-        self.data.borrow().chars().map(|c| c.len_utf16()).sum::<usize>() as u32
+        self.data.borrow().utf16_units().count() as u32
     }
 
     // https://dom.spec.whatwg.org/#dom-characterdata-substringdata
@@ -144,7 +148,10 @@ impl CharacterDataMethods for CharacterData {
         };
         *self.data.borrow_mut() = DOMString::from(new_data);
         self.content_changed();
-        // FIXME: Once we have `Range`, we should implement step 8 to step 11
+        // Steps 8-11.
+        let node = self.upcast::<Node>();
+        node.ranges().replace_code_units(
+            node, offset, count, arg.utf16_units().count() as u32);
         Ok(())
     }
 

components/script/dom/node.rs

@@ -42,6 +42,7 @@ use dom::htmlcollection::HTMLCollection;
 use dom::htmlelement::HTMLElement;
 use dom::nodelist::NodeList;
 use dom::processinginstruction::ProcessingInstruction;
+use dom::range::WeakRangeVec;
 use dom::text::Text;
 use dom::virtualmethods::{VirtualMethods, vtable_for};
 use dom::window::Window;
@@ -108,6 +109,12 @@ pub struct Node {
     /// The maximum version of any inclusive descendant of this node.
     inclusive_descendants_version: Cell<u64>,
 
+    /// A vector of weak references to Range instances of which the start
+    /// or end containers are this node. No range should ever be found
+    /// twice in this vector, even if both the start and end containers
+    /// are this node.
+    ranges: WeakRangeVec,
+
     /// Layout information. Only the layout task may touch this data.
     ///
     /// Must be sent back to the layout task to be destroyed when this
@@ -296,7 +303,7 @@ impl Node {
     /// Removes the given child from this node's list of children.
     ///
     /// Fails unless `child` is a child of this node.
-    fn remove_child(&self, child: &Node) {
+    fn remove_child(&self, child: &Node, cached_index: Option<u32>) {
         assert!(child.parent_node.get().r() == Some(self));
         let prev_sibling = child.GetPreviousSibling();
         match prev_sibling {
@@ -317,9 +324,7 @@ impl Node {
             }
         }
 
-        let context = UnbindContext {
+        let context = UnbindContext::new(self, prev_sibling.r(), cached_index);
-            tree_in_doc: child.is_in_doc(),
-        };
 
         child.prev_sibling.set(None);
         child.next_sibling.set(None);
@@ -437,6 +442,10 @@ impl Node {
         self.children_count.get()
     }
 
+    pub fn ranges(&self) -> &WeakRangeVec {
+        &self.ranges
+    }
+
     #[inline]
     pub fn is_doctype(&self) -> bool {
         self.type_id() == NodeTypeId::DocumentType
@@ -1305,6 +1314,7 @@ impl Node {
             children_count: Cell::new(0u32),
             flags: Cell::new(flags),
             inclusive_descendants_version: Cell::new(0),
+            ranges: WeakRangeVec::new(),
 
             layout_data: LayoutDataRef::new(),
 
@@ -1479,7 +1489,20 @@ impl Node {
         debug_assert!(&*node.owner_doc() == &*parent.owner_doc());
         debug_assert!(child.map_or(true, |child| Some(parent) == child.GetParentNode().r()));
 
-        // Steps 1-2: ranges.
+        // Step 1.
+        let count = if node.is::<DocumentFragment>() {
+            node.children_count()
+        } else {
+            1
+        };
+        // Step 2.
+        if let Some(child) = child {
+            if !parent.ranges.is_empty() {
+                let index = child.index();
+                // Steps 2.1-2.
+                parent.ranges.increase_above(parent, index, count);
+            }
+        }
         let mut new_nodes = RootedVec::new();
         let new_nodes = if let NodeTypeId::DocumentFragment = node.type_id() {
             // Step 3.
@@ -1569,14 +1592,27 @@ impl Node {
     // https://dom.spec.whatwg.org/#concept-node-remove
     fn remove(node: &Node, parent: &Node, suppress_observers: SuppressObserver) {
         assert!(node.GetParentNode().map_or(false, |node_parent| node_parent.r() == parent));
-
+        let cached_index = {
-        // Step 1-5: ranges.
+            if parent.ranges.is_empty() {
+                None
+            } else {
+                // Step 1.
+                let index = node.index();
+                // Steps 2-3 are handled in Node::unbind_from_tree.
+                // Steps 4-5.
+                parent.ranges.decrease_above(parent, index, 1);
+                // Parent had ranges, we needed the index, let's keep track of
+                // it to avoid computing it for other ranges when calling
+                // unbind_from_tree recursively.
+                Some(index)
+            }
+        };
         // Step 6.
         let old_previous_sibling = node.GetPreviousSibling();
         // Steps 7-8: mutation observers.
         // Step 9.
         let old_next_sibling = node.GetNextSibling();
-        parent.remove_child(node);
+        parent.remove_child(node, cached_index);
         if let SuppressObserver::Unsuppressed = suppress_observers {
             vtable_for(&parent).children_changed(
                 &ChildrenMutation::replace(old_previous_sibling.r(),
@@ -2078,28 +2114,26 @@ impl NodeMethods for Node {
 
     // https://dom.spec.whatwg.org/#dom-node-normalize
     fn Normalize(&self) {
-        let mut prev_text: Option<Root<Text>> = None;
+        let mut children = self.children().enumerate().peekable();
-        for child in self.children() {
+        while let Some((_, node)) = children.next() {
-            match child.downcast::<Text>() {
+            if let Some(text) = node.downcast::<Text>() {
-                Some(text) => {
+                let cdata = text.upcast::<CharacterData>();
-                    let characterdata = text.upcast::<CharacterData>();
+                let mut length = cdata.Length();
-                    if characterdata.Length() == 0 {
+                if length == 0 {
-                        Node::remove(&*child, self, SuppressObserver::Unsuppressed);
+                    Node::remove(&node, self, SuppressObserver::Unsuppressed);
-                    } else {
+                    continue;
-                        match prev_text {
-                            Some(ref text_node) => {
-                                let prev_characterdata = text_node.upcast::<CharacterData>();
-                                prev_characterdata.append_data(&**characterdata.data());
-                                Node::remove(&*child, self, SuppressObserver::Unsuppressed);
-                            },
-                            None => prev_text = Some(Root::from_ref(text))
-                        }
-                    }
-                },
-                None => {
-                    child.Normalize();
-                    prev_text = None;
                 }
+                while children.peek().map_or(false, |&(_, ref sibling)| sibling.is::<Text>()) {
+                    let (index, sibling) = children.next().unwrap();
+                    sibling.ranges.drain_to_preceding_text_sibling(&sibling, &node, length);
+                    self.ranges.move_to_text_child_at(self, index as u32, &node, length as u32);
+                    let sibling_cdata = sibling.downcast::<CharacterData>().unwrap();
+                    length += sibling_cdata.Length();
+                    cdata.append_data(&sibling_cdata.data());
+                    Node::remove(&sibling, self, SuppressObserver::Unsuppressed);
+                }
+            } else {
+                node.Normalize();
             }
         }
     }
@@ -2338,6 +2372,13 @@ impl VirtualMethods for Node {
             list.as_children_list().children_changed(mutation);
         }
     }
+
+    // This handles the ranges mentioned in steps 2-3 when removing a node.
+    // https://dom.spec.whatwg.org/#concept-node-remove
+    fn unbind_from_tree(&self, context: &UnbindContext) {
+        self.super_type().unwrap().unbind_from_tree(context);
+        self.ranges.drain_to_parent(context, self);
+    }
 }
 
 /// A summary of the changes that happened to a node.
@@ -2413,7 +2454,39 @@ impl<'a> ChildrenMutation<'a> {
 
 /// The context of the unbinding from a tree of a node when one of its
 /// inclusive ancestors is removed.
-pub struct UnbindContext {
+pub struct UnbindContext<'a> {
+    /// The index of the inclusive ancestor that was removed.
+    index: Cell<Option<u32>>,
+    /// The parent of the inclusive ancestor that was removed.
+    pub parent: &'a Node,
+    /// The previous sibling of the inclusive ancestor that was removed.
+    prev_sibling: Option<&'a Node>,
     /// Whether the tree is in a document.
     pub tree_in_doc: bool,
 }
+
+impl<'a> UnbindContext<'a> {
+    /// Create a new `UnbindContext` value.
+    fn new(parent: &'a Node,
+           prev_sibling: Option<&'a Node>,
+           cached_index: Option<u32>) -> Self {
+        UnbindContext {
+            index: Cell::new(cached_index),
+            parent: parent,
+            prev_sibling: prev_sibling,
+            tree_in_doc: parent.is_in_doc(),
+        }
+    }
+
+    /// The index of the inclusive ancestor that was removed from the tree.
+    #[allow(unsafe_code)]
+    pub fn index(&self) -> u32 {
+        if let Some(index) = self.index.get() {
+            return index;
+        }
+        let index =
+            self.prev_sibling.map(|sibling| sibling.index() + 1).unwrap_or(0);
+        self.index.set(Some(index));
+        index
+    }
+}

components/script/dom/range.rs

@@ -16,14 +16,17 @@ use dom::bindings::inheritance::Castable;
 use dom::bindings::inheritance::{CharacterDataTypeId, NodeTypeId};
 use dom::bindings::js::{JS, MutHeap, Root, RootedReference};
 use dom::bindings::reflector::{Reflector, reflect_dom_object};
-use dom::bindings::trace::RootedVec;
+use dom::bindings::trace::{JSTraceable, RootedVec};
+use dom::bindings::weakref::{WeakRef, WeakRefVec};
 use dom::characterdata::CharacterData;
 use dom::document::Document;
 use dom::documentfragment::DocumentFragment;
-use dom::node::Node;
+use dom::node::{Node, UnbindContext};
 use dom::text::Text;
-use std::cell::Cell;
+use js::jsapi::JSTracer;
+use std::cell::{Cell, UnsafeCell};
 use std::cmp::{Ord, Ordering, PartialEq, PartialOrd};
+use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
 #[dom_struct]
@@ -52,10 +55,15 @@ impl Range {
                start_container: &Node, start_offset: u32,
                end_container: &Node, end_offset: u32)
                -> Root<Range> {
-        reflect_dom_object(box Range::new_inherited(start_container, start_offset,
+        let range = reflect_dom_object(box Range::new_inherited(start_container, start_offset,
-                                                    end_container, end_offset),
+                                                                end_container, end_offset),
-                           GlobalRef::Window(document.window()),
+                                       GlobalRef::Window(document.window()),
-                           RangeBinding::Wrap)
+                                       RangeBinding::Wrap);
+        start_container.ranges().push(WeakRef::new(&range));
+        if start_container != end_container {
+            end_container.ranges().push(WeakRef::new(&range));
+        }
+        range
     }
 
     // https://dom.spec.whatwg.org/#dom-range
@@ -121,19 +129,31 @@ impl Range {
     }
 
     // https://dom.spec.whatwg.org/#concept-range-bp-set
-    pub fn set_start(&self, node: &Node, offset: u32) {
+    fn set_start(&self, node: &Node, offset: u32) {
-        self.start.set(node, offset);
+        if &self.start.node != node {
-        if !(self.start <= self.end) {
+            if self.start.node == self.end.node {
-            self.end.set(node, offset);
+                node.ranges().push(WeakRef::new(&self));
+            } else if &self.end.node == node {
+                self.StartContainer().ranges().remove(self);
+            } else {
+                node.ranges().push(self.StartContainer().ranges().remove(self));
+            }
         }
+        self.start.set(node, offset);
     }
 
     // https://dom.spec.whatwg.org/#concept-range-bp-set
-    pub fn set_end(&self, node: &Node, offset: u32) {
+    fn set_end(&self, node: &Node, offset: u32) {
-        self.end.set(node, offset);
+        if &self.end.node != node {
-        if !(self.end >= self.start) {
+            if self.end.node == self.start.node {
-            self.start.set(node, offset);
+                node.ranges().push(WeakRef::new(&self));
+            } else if &self.start.node == node {
+                self.EndContainer().ranges().remove(self);
+            } else {
+                node.ranges().push(self.EndContainer().ranges().remove(self));
+            }
         }
+        self.end.set(node, offset);
     }
 
     // https://dom.spec.whatwg.org/#dom-range-comparepointnode-offset
@@ -215,8 +235,12 @@ impl RangeMethods for Range {
             // Step 2.
             Err(Error::IndexSize)
         } else {
-            // Step 3-4.
+            // Step 3.
             self.set_start(node, offset);
+            if !(self.start <= self.end) {
+                // Step 4.
+                self.set_end(node, offset);
+            }
             Ok(())
         }
     }
@@ -230,8 +254,12 @@ impl RangeMethods for Range {
             // Step 2.
             Err(Error::IndexSize)
         } else {
-            // Step 3-4.
+            // Step 3.
             self.set_end(node, offset);
+            if !(self.end >= self.start) {
+                // Step 4.
+                self.set_start(node, offset);
+            }
             Ok(())
         }
     }
@@ -263,9 +291,9 @@ impl RangeMethods for Range {
     // https://dom.spec.whatwg.org/#dom-range-collapse
     fn Collapse(&self, to_start: bool) {
         if to_start {
-            self.end.set(&self.StartContainer(), self.StartOffset());
+            self.set_end(&self.StartContainer(), self.StartOffset());
         } else {
-            self.start.set(&self.EndContainer(), self.EndOffset());
+            self.set_start(&self.EndContainer(), self.EndOffset());
         }
     }
 
@@ -276,9 +304,9 @@ impl RangeMethods for Range {
         // Step 3.
         let index = node.index();
         // Step 4.
-        self.start.set(&parent, index);
+        self.set_start(&parent, index);
         // Step 5.
-        self.end.set(&parent, index + 1);
+        self.set_end(&parent, index + 1);
         Ok(())
     }
 
@@ -291,9 +319,9 @@ impl RangeMethods for Range {
         // Step 2.
         let length = node.len();
         // Step 3.
-        self.start.set(node, 0);
+        self.set_start(node, 0);
         // Step 4.
-        self.end.set(node, length);
+        self.set_end(node, length);
         Ok(())
     }
 
@@ -833,10 +861,12 @@ impl BoundaryPoint {
         }
     }
 
-    fn set(&self, node: &Node, offset: u32) {
+    pub fn set(&self, node: &Node, offset: u32) {
-        debug_assert!(!node.is_doctype());
-        debug_assert!(offset <= node.len());
         self.node.set(node);
+        self.set_offset(offset);
+    }
+
+    pub fn set_offset(&self, offset: u32) {
         self.offset.set(offset);
     }
 }
@@ -894,3 +924,259 @@ fn bp_position(a_node: &Node, a_offset: u32,
         Some(Ordering::Less)
     }
 }
+
+pub struct WeakRangeVec {
+    cell: UnsafeCell<WeakRefVec<Range>>,
+}
+
+#[allow(unsafe_code)]
+impl WeakRangeVec {
+    /// Create a new vector of weak references.
+    pub fn new() -> Self {
+        WeakRangeVec { cell: UnsafeCell::new(WeakRefVec::new()) }
+    }
+
+    /// Whether that vector of ranges is empty.
+    pub fn is_empty(&self) -> bool {
+        unsafe { (*self.cell.get()).is_empty() }
+    }
+
+    /// Used for steps 2.1-2. when inserting a node.
+    /// https://dom.spec.whatwg.org/#concept-node-insert
+    pub fn increase_above(&self, node: &Node, offset: u32, delta: u32) {
+        self.map_offset_above(node, offset, |offset| offset + delta);
+    }
+
+    /// Used for steps 4-5. when removing a node.
+    /// https://dom.spec.whatwg.org/#concept-node-remove
+    pub fn decrease_above(&self, node: &Node, offset: u32, delta: u32) {
+        self.map_offset_above(node, offset, |offset| offset - delta);
+    }
+
+    /// Used for steps 2-3. when removing a node.
+    /// https://dom.spec.whatwg.org/#concept-node-remove
+    pub fn drain_to_parent(&self, context: &UnbindContext, child: &Node) {
+        if self.is_empty() {
+            return;
+        }
+
+        let offset = context.index();
+        let parent = context.parent;
+        unsafe {
+            let mut ranges = &mut *self.cell.get();
+
+            ranges.update(|entry| {
+                let range = entry.root().unwrap();
+                if &range.start.node == parent || &range.end.node == parent {
+                    entry.remove();
+                }
+                if &range.start.node == child {
+                    range.start.set(context.parent, offset);
+                }
+                if &range.end.node == child {
+                    range.end.set(context.parent, offset);
+                }
+            });
+
+            (*context.parent.ranges().cell.get()).extend(ranges.drain(..));
+        }
+    }
+
+    /// Used for steps 7.1-2. when normalizing a node.
+    /// https://dom.spec.whatwg.org/#dom-node-normalize
+    pub fn drain_to_preceding_text_sibling(&self, node: &Node, sibling: &Node, length: u32) {
+        if self.is_empty() {
+            return;
+        }
+
+        unsafe {
+            let mut ranges = &mut *self.cell.get();
+
+            ranges.update(|entry| {
+                let range = entry.root().unwrap();
+                if &range.start.node == sibling || &range.end.node == sibling {
+                    entry.remove();
+                }
+                if &range.start.node == node {
+                    range.start.set(sibling, range.StartOffset() + length);
+                }
+                if &range.end.node == node {
+                    range.end.set(sibling, range.EndOffset() + length);
+                }
+            });
+
+            (*sibling.ranges().cell.get()).extend(ranges.drain(..));
+        }
+    }
+
+    /// Used for steps 7.3-4. when normalizing a node.
+    /// https://dom.spec.whatwg.org/#dom-node-normalize
+    pub fn move_to_text_child_at(&self,
+                                 node: &Node, offset: u32,
+                                 child: &Node, new_offset: u32) {
+        unsafe {
+            let child_ranges = &mut *child.ranges().cell.get();
+
+            (*self.cell.get()).update(|entry| {
+                let range = entry.root().unwrap();
+
+                let node_is_start = &range.start.node == node;
+                let node_is_end = &range.end.node == node;
+
+                let move_start = node_is_start && range.StartOffset() == offset;
+                let move_end = node_is_end && range.EndOffset() == offset;
+
+                let remove_from_node = move_start && move_end ||
+                                       move_start && !node_is_end ||
+                                       move_end && !node_is_start;
+
+                let already_in_child = &range.start.node == child || &range.end.node == child;
+                let push_to_child = !already_in_child && (move_start || move_end);
+
+                if remove_from_node {
+                    let ref_ = entry.remove();
+                    if push_to_child {
+                        child_ranges.push(ref_);
+                    }
+                } else if push_to_child {
+                    child_ranges.push(WeakRef::new(&range));
+                }
+
+                if move_start {
+                    range.start.set(child, new_offset);
+                }
+                if move_end {
+                    range.end.set(child, new_offset);
+                }
+            });
+        }
+    }
+
+    /// Used for steps 8-11. when replacing character data.
+    /// https://dom.spec.whatwg.org/#concept-cd-replace
+    pub fn replace_code_units(&self,
+                              node: &Node, offset: u32,
+                              removed_code_units: u32, added_code_units: u32) {
+        self.map_offset_above(node, offset, |range_offset| {
+            if range_offset <= offset + removed_code_units {
+                offset
+            } else {
+                range_offset + added_code_units - removed_code_units
+            }
+        });
+    }
+
+    /// Used for steps 7.2-3. when splitting a text node.
+    /// https://dom.spec.whatwg.org/#concept-text-split
+    pub fn move_to_following_text_sibling_above(&self,
+                                                node: &Node, offset: u32,
+                                                sibling: &Node) {
+        unsafe {
+            let sibling_ranges = &mut *sibling.ranges().cell.get();
+
+            (*self.cell.get()).update(|entry| {
+                let range = entry.root().unwrap();
+                let start_offset = range.StartOffset();
+                let end_offset = range.EndOffset();
+
+                let node_is_start = &range.start.node == node;
+                let node_is_end = &range.end.node == node;
+
+                let move_start = node_is_start && start_offset > offset;
+                let move_end = node_is_end && end_offset > offset;
+
+                let remove_from_node = move_start && move_end ||
+                                       move_start && !node_is_end ||
+                                       move_end && !node_is_start;
+
+                let already_in_sibling =
+                    &range.start.node == sibling || &range.end.node == sibling;
+                let push_to_sibling = !already_in_sibling && (move_start || move_end);
+
+                if remove_from_node {
+                    let ref_ = entry.remove();
+                    if push_to_sibling {
+                        sibling_ranges.push(ref_);
+                    }
+                } else if push_to_sibling {
+                    sibling_ranges.push(WeakRef::new(&range));
+                }
+
+                if move_start {
+                    range.start.set(sibling, start_offset - offset);
+                }
+                if move_end {
+                    range.end.set(sibling, end_offset - offset);
+                }
+            });
+        }
+    }
+
+    /// Used for steps 7.4-5. when splitting a text node.
+    /// https://dom.spec.whatwg.org/#concept-text-split
+    pub fn increment_at(&self, node: &Node, offset: u32) {
+        unsafe {
+            (*self.cell.get()).update(|entry| {
+                let range = entry.root().unwrap();
+                if &range.start.node == node && offset == range.StartOffset() {
+                    range.start.set_offset(offset + 1);
+                }
+                if &range.end.node == node && offset == range.EndOffset() {
+                    range.end.set_offset(offset + 1);
+                }
+            });
+        }
+    }
+
+    /// Used for steps 9.1-2. when splitting a text node.
+    /// https://dom.spec.whatwg.org/#concept-text-split
+    pub fn clamp_above(&self, node: &Node, offset: u32) {
+        self.map_offset_above(node, offset, |_| offset);
+    }
+
+    fn map_offset_above<F: FnMut(u32) -> u32>(&self, node: &Node, offset: u32, mut f: F) {
+        unsafe {
+            (*self.cell.get()).update(|entry| {
+                let range = entry.root().unwrap();
+                let start_offset = range.StartOffset();
+                if &range.start.node == node && start_offset > offset {
+                    range.start.set_offset(f(start_offset));
+                }
+                let end_offset = range.EndOffset();
+                if &range.end.node == node && end_offset > offset {
+                    range.end.set_offset(f(end_offset));
+                }
+            });
+        }
+    }
+
+    fn push(&self, ref_: WeakRef<Range>) {
+        unsafe {
+            (*self.cell.get()).push(ref_);
+        }
+    }
+
+    fn remove(&self, range: &Range) -> WeakRef<Range> {
+        unsafe {
+            let ranges = &mut *self.cell.get();
+            let position = ranges.iter().position(|ref_| {
+                ref_ == range
+            }).unwrap();
+            ranges.swap_remove(position)
+        }
+    }
+}
+
+#[allow(unsafe_code)]
+impl HeapSizeOf for WeakRangeVec {
+    fn heap_size_of_children(&self) -> usize {
+        unsafe { (*self.cell.get()).heap_size_of_children() }
+    }
+}
+
+#[allow(unsafe_code)]
+impl JSTraceable for WeakRangeVec {
+    fn trace(&self, _: *mut JSTracer) {
+        unsafe { (*self.cell.get()).retain_alive() }
+    }
+}

components/script/dom/text.rs

@@ -62,15 +62,18 @@ impl TextMethods for Text {
         // Step 6.
         let parent = node.GetParentNode();
         if let Some(ref parent) = parent {
-            // Step 7.
+            // Step 7.1.
             parent.InsertBefore(new_node.upcast(), node.GetNextSibling().r()).unwrap();
-            // TODO: Ranges.
+            // Steps 7.2-3.
+            node.ranges().move_to_following_text_sibling_above(node, offset, new_node.upcast());
+            // Steps 7.4-5.
+            parent.ranges().increment_at(&parent, node.index() + 1);
         }
         // Step 8.
         cdata.DeleteData(offset, count).unwrap();
         if parent.is_none() {
             // Step 9.
-            // TODO: Ranges
+            node.ranges().clamp_above(&node, offset);
         }
         // Step 10.
         Ok(new_node)

components/script/lib.rs

@@ -13,7 +13,6 @@
 #![feature(custom_derive)]
 #![feature(fnbox)]
 #![feature(hashmap_hasher)]
-#![feature(iter_arith)]
 #![feature(mpsc_select)]
 #![feature(nonzero)]
 #![feature(on_unimplemented)]

tests/unit/script/size_of.rs

@@ -38,10 +38,10 @@ macro_rules! sizeof_checker (
 
 // Update the sizes here
 sizeof_checker!(size_event_target, EventTarget, 40);
-sizeof_checker!(size_node, Node, 160);
+sizeof_checker!(size_node, Node, 184);
-sizeof_checker!(size_element, Element, 304);
+sizeof_checker!(size_element, Element, 328);
-sizeof_checker!(size_htmlelement, HTMLElement, 320);
+sizeof_checker!(size_htmlelement, HTMLElement, 344);
-sizeof_checker!(size_div, HTMLDivElement, 320);
+sizeof_checker!(size_div, HTMLDivElement, 344);
-sizeof_checker!(size_span, HTMLSpanElement, 320);
+sizeof_checker!(size_span, HTMLSpanElement, 344);
-sizeof_checker!(size_text, Text, 192);
+sizeof_checker!(size_text, Text, 216);
-sizeof_checker!(size_characterdata, CharacterData, 192);
+sizeof_checker!(size_characterdata, CharacterData, 216);

tests/wpt/metadata/dom/ranges/Range-deleteContents.html.ini

@@ -1,23 +1,5 @@
 [Range-deleteContents.html]
   type: testharness
-  [Resulting cursor position for range 1 [paras[0\].firstChild, 0, paras[0\].firstChild, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 2 [paras[0\].firstChild, 2, paras[0\].firstChild, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 3 [paras[0\].firstChild, 2, paras[0\].firstChild, 9\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 5 [paras[1\].firstChild, 2, paras[1\].firstChild, 9\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 7 [detachedPara1.firstChild, 2, detachedPara1.firstChild, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 9 [foreignPara1.firstChild, 2, foreignPara1.firstChild, 8\]]
-    expected: FAIL
-
   [Resulting cursor position for range 18 [paras[0\].firstChild, 0, paras[1\].firstChild, 0\]]
     expected: FAIL
 
@@ -30,27 +12,6 @@
   [Resulting DOM for range 24 [document, 0, document, 2\]]
     expected: FAIL
 
-  [Resulting cursor position for range 25 [comment, 2, comment, 3\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 30 [detachedTextNode, 0, detachedTextNode, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 31 [detachedForeignTextNode, 0, detachedForeignTextNode, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 32 [detachedXmlTextNode, 0, detachedXmlTextNode, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 33 [detachedComment, 3, detachedComment, 4\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 34 [detachedForeignComment, 0, detachedForeignComment, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 35 [detachedXmlComment, 2, detachedXmlComment, 6\]]
-    expected: FAIL
-
   [Resulting DOM for range 10 [document.documentElement, 0, document.documentElement, 1\]]
     expected: FAIL
 
@@ -66,21 +27,6 @@
   [Resulting DOM for range 27 [foreignDoc, 1, foreignComment, 2\]]
     expected: FAIL
 
-  [Resulting cursor position for range 37 [processingInstruction, 0, processingInstruction, 4\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 38 [paras[1\].firstChild, 0, paras[1\].firstChild, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 39 [paras[1\].firstChild, 2, paras[1\].firstChild, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 40 [detachedPara1.firstChild, 0, detachedPara1.firstChild, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 41 [foreignPara1.firstChild, 0, foreignPara1.firstChild, 1\]]
-    expected: FAIL
-
   [Resulting DOM for range 49 [document, 1, document, 2\]]
     expected: FAIL
 

tests/wpt/metadata/dom/ranges/Range-extractContents.html.ini

@@ -1,23 +1,5 @@
 [Range-extractContents.html]
   type: testharness
-  [Resulting cursor position for range 1 [paras[0\].firstChild, 0, paras[0\].firstChild, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 2 [paras[0\].firstChild, 2, paras[0\].firstChild, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 3 [paras[0\].firstChild, 2, paras[0\].firstChild, 9\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 5 [paras[1\].firstChild, 2, paras[1\].firstChild, 9\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 7 [detachedPara1.firstChild, 2, detachedPara1.firstChild, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 9 [foreignPara1.firstChild, 2, foreignPara1.firstChild, 8\]]
-    expected: FAIL
-
   [Resulting cursor position for range 18 [paras[0\].firstChild, 0, paras[1\].firstChild, 0\]]
     expected: FAIL
 
@@ -27,42 +9,6 @@
   [Resulting cursor position for range 20 [paras[0\].firstChild, 3, paras[3\], 1\]]
     expected: FAIL
 
-  [Resulting cursor position for range 25 [comment, 2, comment, 3\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 30 [detachedTextNode, 0, detachedTextNode, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 31 [detachedForeignTextNode, 0, detachedForeignTextNode, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 32 [detachedXmlTextNode, 0, detachedXmlTextNode, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 33 [detachedComment, 3, detachedComment, 4\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 34 [detachedForeignComment, 0, detachedForeignComment, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 35 [detachedXmlComment, 2, detachedXmlComment, 6\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 37 [processingInstruction, 0, processingInstruction, 4\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 38 [paras[1\].firstChild, 0, paras[1\].firstChild, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 39 [paras[1\].firstChild, 2, paras[1\].firstChild, 8\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 40 [detachedPara1.firstChild, 0, detachedPara1.firstChild, 1\]]
-    expected: FAIL
-
-  [Resulting cursor position for range 41 [foreignPara1.firstChild, 0, foreignPara1.firstChild, 1\]]
-    expected: FAIL
-
   [Resulting cursor position for range 50 [paras[2\].firstChild, 4, comment, 2\]]
     expected: FAIL