Move EventState to rust-selectors.

11 files changed, 68 insertions, 100 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index c78429f8368..f18719073fc 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -62,6 +62,7 @@ use profile_traits::time::ProfilerChan as TimeProfilerChan;
 use script_task::ScriptChan;
 use script_traits::{TimerEventChan, TimerEventId, TimerSource, UntrustedNodeAddress};
 use selectors::parser::PseudoElement;
+use selectors::states::*;
 use serde::{Deserialize, Serialize};
 use smallvec::SmallVec;
 use std::boxed::FnBox;
@@ -308,6 +309,7 @@ no_jsmanaged_fields!(TimeProfilerChan);
 no_jsmanaged_fields!(MemProfilerChan);
 no_jsmanaged_fields!(PseudoElement);
 no_jsmanaged_fields!(Length);
+no_jsmanaged_fields!(ElementState);
 
 impl JSTraceable for Box<ScriptChan + Send> {
     #[inline]
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 2ad0a12262f..0a94f9f5504 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -32,7 +32,7 @@ use dom::customevent::CustomEvent;
 use dom::documentfragment::DocumentFragment;
 use dom::documenttype::DocumentType;
 use dom::domimplementation::DOMImplementation;
-use dom::element::{Element, ElementCreator, EventState};
+use dom::element::{Element, ElementCreator};
 use dom::event::{Event, EventBubbles, EventCancelable};
 use dom::eventtarget::{EventTarget};
 use dom::htmlanchorelement::HTMLAnchorElement;
@@ -85,6 +85,7 @@ use net_traits::{AsyncResponseTarget, PendingAsyncLoad};
 use num::ToPrimitive;
 use script_task::{MainThreadScriptMsg, Runnable};
 use script_traits::{MouseButton, UntrustedNodeAddress};
+use selectors::states::*;
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::boxed::FnBox;
@@ -174,8 +175,8 @@ pub struct Document {
     /// This field is set to the document itself for inert documents.
     /// https://html.spec.whatwg.org/multipage/#appropriate-template-contents-owner-document
     appropriate_template_contents_owner_document: MutNullableHeap<JS<Document>>,
-    // The collection of EventStates that have been changed since the last restyle.
-    event_state_changes: DOMRefCell<HashMap<JS<Element>, EventState>>,
+    // The collection of ElementStates that have been changed since the last restyle.
+    element_state_changes: DOMRefCell<HashMap<JS<Element>, ElementState>>,
 }
 
 impl PartialEq for Document {
@@ -305,7 +306,7 @@ impl Document {
 
     pub fn needs_reflow(&self) -> bool {
         self.GetDocumentElement().is_some() &&
-        (self.upcast::<Node>().get_has_dirty_descendants() || !self.event_state_changes.borrow().is_empty())
+        (self.upcast::<Node>().get_has_dirty_descendants() || !self.element_state_changes.borrow().is_empty())
     }
 
     /// Returns the first `base` element in the DOM that has an `href` attribute.
@@ -1185,7 +1186,7 @@ pub enum DocumentSource {
 #[allow(unsafe_code)]
 pub trait LayoutDocumentHelpers {
     unsafe fn is_html_document_for_layout(&self) -> bool;
-    unsafe fn drain_event_state_changes(&self) -> Vec<(LayoutJS<Element>, EventState)>;
+    unsafe fn drain_element_state_changes(&self) -> Vec<(LayoutJS<Element>, ElementState)>;
 }
 
 #[allow(unsafe_code)]
@@ -1197,8 +1198,8 @@ impl LayoutDocumentHelpers for LayoutJS<Document> {
 
     #[inline]
     #[allow(unrooted_must_root)]
-    unsafe fn drain_event_state_changes(&self) -> Vec<(LayoutJS<Element>, EventState)> {
-        let mut changes = (*self.unsafe_get()).event_state_changes.borrow_mut_for_layout();
+    unsafe fn drain_element_state_changes(&self) -> Vec<(LayoutJS<Element>, ElementState)> {
+        let mut changes = (*self.unsafe_get()).element_state_changes.borrow_mut_for_layout();
         let drain = changes.drain();
         let layout_drain = drain.map(|(k, v)| (k.to_layout(), v));
         Vec::from_iter(layout_drain)
@@ -1268,7 +1269,7 @@ impl Document {
             reflow_timeout: Cell::new(None),
             base_element: Default::default(),
             appropriate_template_contents_owner_document: Default::default(),
-            event_state_changes: DOMRefCell::new(HashMap::new()),
+            element_state_changes: DOMRefCell::new(HashMap::new()),
         }
     }
 
@@ -1334,12 +1335,12 @@ impl Document {
         self.idmap.borrow().get(&id).map(|ref elements| (*elements)[0].root())
     }
 
-    pub fn record_event_state_change(&self, el: &Element, which: EventState) {
-        let mut map = self.event_state_changes.borrow_mut();
+    pub fn record_element_state_change(&self, el: &Element, which: ElementState) {
+        let mut map = self.element_state_changes.borrow_mut();
         let empty;
         {
             let states = map.entry(JS::from_ref(el))
-                            .or_insert(EventState::empty());
+                            .or_insert(ElementState::empty());
             states.toggle(which);
             empty = states.is_empty();
         }
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index 50f571452b6..46628935bb1 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -26,6 +26,7 @@ use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, LayoutJS, MutNullableHeap};
 use dom::bindings::js::{Root, RootedReference};
+use dom::bindings::trace::JSTraceable;
 use dom::bindings::utils::XMLName::InvalidXMLName;
 use dom::bindings::utils::{namespace_from_domstring, validate_and_extract, xml_name_type};
 use dom::characterdata::CharacterData;
@@ -63,8 +64,8 @@ use html5ever::serialize::TraversalScope;
 use html5ever::serialize::TraversalScope::{ChildrenOnly, IncludeNode};
 use html5ever::tree_builder::{LimitedQuirks, NoQuirks, Quirks};
 use selectors::matching::{DeclarationBlock, matches};
-use selectors::parser::parse_author_origin_selector_list_from_str;
-use selectors::parser::{AttrSelector, NamespaceConstraint};
+use selectors::parser::{AttrSelector, NamespaceConstraint, parse_author_origin_selector_list_from_str};
+use selectors::states::*;
 use smallvec::VecLike;
 use std::ascii::AsciiExt;
 use std::borrow::{Cow, ToOwned};
@@ -80,35 +81,12 @@ use style::properties::{PropertyDeclaration, PropertyDeclarationBlock, parse_sty
 use style::values::CSSFloat;
 use style::values::specified::{self, CSSColor, CSSRGBA};
 use url::UrlParser;
+use util::mem::HeapSizeOf;
 use util::str::{DOMString, LengthOrPercentageOrAuto};
 
-bitflags! {
-    #[doc = "Element Event States."]
-    #[derive(JSTraceable, HeapSizeOf)]
-    flags EventState: u16 {
-        #[doc = "The mouse is down on this element. \
-                 (https://html.spec.whatwg.org/multipage/#selector-active). \
-                 FIXME(#7333): set/unset this when appropriate"]
-        const IN_ACTIVE_STATE = 0x01,
-        #[doc = "This element has focus.
-                 https://html.spec.whatwg.org/multipage/scripting.html#selector-focus"]
-        const IN_FOCUS_STATE = 0x02,
-        #[doc = "The mouse is hovering over this element. \
-                 https://html.spec.whatwg.org/multipage/scripting.html#selector-hover"]
-        const IN_HOVER_STATE = 0x04,
-        #[doc = "Content is enabled (and can be disabled). \
-                 http://www.whatwg.org/html/#selector-enabled"]
-        const IN_ENABLED_STATE = 0x08,
-        #[doc = "Content is disabled. \
-                 http://www.whatwg.org/html/#selector-disabled"]
-        const IN_DISABLED_STATE = 0x10,
-        #[doc = "Content is checked. \
-                 https://html.spec.whatwg.org/multipage/scripting.html#selector-checked"]
-        const IN_CHECKED_STATE = 0x20,
-        #[doc = "https://html.spec.whatwg.org/multipage/scripting.html#selector-indeterminate"]
-        const IN_INDETERMINATE_STATE = 0x40,
-    }
-}
+// TODO: Update focus state when the top-level browsing context gains or loses system focus,
+// and when the element enters or leaves a browsing context container.
+// https://html.spec.whatwg.org/multipage/#selector-focus
 
 #[dom_struct]
 pub struct Element {
@@ -121,7 +99,7 @@ pub struct Element {
     style_attribute: DOMRefCell<Option<PropertyDeclarationBlock>>,
     attr_list: MutNullableHeap<JS<NamedNodeMap>>,
     class_list: MutNullableHeap<JS<DOMTokenList>>,
-    event_state: Cell<EventState>,
+    state: Cell<ElementState>,
 }
 
 impl PartialEq for Element {
@@ -150,11 +128,11 @@ impl Element {
     pub fn new_inherited(local_name: DOMString,
                          namespace: Namespace, prefix: Option<DOMString>,
                          document: &Document) -> Element {
-        Element::new_inherited_with_state(EventState::empty(), local_name,
+        Element::new_inherited_with_state(ElementState::empty(), local_name,
                                           namespace, prefix, document)
     }
 
-    pub fn new_inherited_with_state(state: EventState, local_name: DOMString,
+    pub fn new_inherited_with_state(state: ElementState, local_name: DOMString,
                                     namespace: Namespace, prefix: Option<DOMString>,
                                     document: &Document)
                                     -> Element {
@@ -168,7 +146,7 @@ impl Element {
             style_attribute: DOMRefCell::new(None),
             attr_list: Default::default(),
             class_list: Default::default(),
-            event_state: Cell::new(state),
+            state: Cell::new(state),
         }
     }
 
@@ -261,7 +239,7 @@ pub trait LayoutElementHelpers {
     fn get_checked_state_for_layout(&self) -> bool;
     fn get_indeterminate_state_for_layout(&self) -> bool;
 
-    fn get_event_state_for_layout(&self) -> EventState;
+    fn get_state_for_layout(&self) -> ElementState;
 }
 
 impl LayoutElementHelpers for LayoutJS<Element> {
@@ -614,9 +592,9 @@ impl LayoutElementHelpers for LayoutJS<Element> {
 
     #[inline]
     #[allow(unsafe_code)]
-    fn get_event_state_for_layout(&self) -> EventState {
+    fn get_state_for_layout(&self) -> ElementState {
         unsafe {
-            (*self.unsafe_get()).event_state.get()
+            (*self.unsafe_get()).state.get()
         }
     }
 }
@@ -1592,6 +1570,16 @@ impl VirtualMethods for Element {
     }
 }
 
+macro_rules! state_getter {
+    ($(
+        $(#[$Flag_attr: meta])*
+        state $css: expr => $variant: ident / $method: ident /
+        $flag: ident = $value: expr,
+    )+) => {
+        $( fn $method(&self) -> bool { Element::get_state(self).contains($flag) } )+
+    }
+}
+
 impl<'a> ::selectors::Element for Root<Element> {
     fn parent_element(&self) -> Option<Root<Element>> {
         self.upcast::<Node>().GetParentElement()
@@ -1658,42 +1646,11 @@ impl<'a> ::selectors::Element for Root<Element> {
         self.namespace()
     }
 
-    fn get_hover_state(&self) -> bool {
-        Element::get_hover_state(self)
-    }
-
-    fn get_active_state(&self) -> bool {
-        Element::get_active_state(self)
-    }
-
-    fn get_focus_state(&self) -> bool {
-        // TODO: Also check whether the top-level browsing context has the system focus,
-        // and whether this element is a browsing context container.
-        // https://html.spec.whatwg.org/multipage/#selector-focus
-        Element::get_focus_state(self)
-    }
+    state_pseudo_classes!(state_getter);
 
     fn get_id(&self) -> Option<Atom> {
         self.id_attribute.borrow().clone()
     }
-    fn get_disabled_state(&self) -> bool {
-        Element::get_disabled_state(self)
-    }
-    fn get_enabled_state(&self) -> bool {
-        Element::get_enabled_state(self)
-    }
-    fn get_checked_state(&self) -> bool {
-        match self.downcast::<HTMLInputElement>() {
-            Some(input) => input.Checked(),
-            None => false,
-        }
-    }
-    fn get_indeterminate_state(&self) -> bool {
-        match self.downcast::<HTMLInputElement>() {
-            Some(input) => input.get_indeterminate_state(),
-            None => false,
-        }
-    }
     fn has_class(&self, name: &Atom) -> bool {
         Element::has_class(&**self, name)
     }
@@ -1843,12 +1800,12 @@ impl Element {
         self.set_click_in_progress(false);
     }
 
-    pub fn get_state(&self) -> EventState {
-        self.event_state.get()
+    pub fn get_state(&self) -> ElementState {
+        self.state.get()
     }
 
-    pub fn set_state(&self, which: EventState, value: bool) {
-        let mut state = self.event_state.get();
+    pub fn set_state(&self, which: ElementState, value: bool) {
+        let mut state = self.state.get();
         if state.contains(which) == value {
             return
         }
@@ -1856,14 +1813,14 @@ impl Element {
             true => state.insert(which),
             false => state.remove(which),
         };
-        self.event_state.set(state);
+        self.state.set(state);
 
         let node = self.upcast::<Node>();
-        node.owner_doc().record_event_state_change(self, which);
+        node.owner_doc().record_element_state_change(self, which);
     }
 
     pub fn get_active_state(&self) -> bool {
-        self.event_state.get().contains(IN_ACTIVE_STATE)
+        self.state.get().contains(IN_ACTIVE_STATE)
     }
 
     pub fn set_active_state(&self, value: bool) {
@@ -1871,7 +1828,7 @@ impl Element {
     }
 
     pub fn get_focus_state(&self) -> bool {
-        self.event_state.get().contains(IN_FOCUS_STATE)
+        self.state.get().contains(IN_FOCUS_STATE)
     }
 
     pub fn set_focus_state(&self, value: bool) {
@@ -1879,7 +1836,7 @@ impl Element {
     }
 
     pub fn get_hover_state(&self) -> bool {
-        self.event_state.get().contains(IN_HOVER_STATE)
+        self.state.get().contains(IN_HOVER_STATE)
     }
 
     pub fn set_hover_state(&self, value: bool) {
@@ -1887,7 +1844,7 @@ impl Element {
     }
 
     pub fn get_enabled_state(&self) -> bool {
-        self.event_state.get().contains(IN_ENABLED_STATE)
+        self.state.get().contains(IN_ENABLED_STATE)
     }
 
     pub fn set_enabled_state(&self, value: bool) {
@@ -1895,7 +1852,7 @@ impl Element {
     }
 
     pub fn get_disabled_state(&self) -> bool {
-        self.event_state.get().contains(IN_DISABLED_STATE)
+        self.state.get().contains(IN_DISABLED_STATE)
     }
 
     pub fn set_disabled_state(&self, value: bool) {
diff --git a/components/script/dom/htmlbuttonelement.rs b/components/script/dom/htmlbuttonelement.rs
index 5146c7e4888..203f04c0009 100644
--- a/components/script/dom/htmlbuttonelement.rs
+++ b/components/script/dom/htmlbuttonelement.rs
@@ -9,7 +9,7 @@ use dom::bindings::codegen::Bindings::HTMLButtonElementBinding::HTMLButtonElemen
 use dom::bindings::conversions::Castable;
 use dom::bindings::js::Root;
 use dom::document::Document;
-use dom::element::{AttributeMutation, Element, IN_ENABLED_STATE};
+use dom::element::{AttributeMutation, Element};
 use dom::event::Event;
 use dom::eventtarget::EventTarget;
 use dom::htmlelement::HTMLElement;
@@ -19,6 +19,7 @@ use dom::htmlformelement::{SubmittedFrom, HTMLFormElement};
 use dom::node::{Node, document_from_node, window_from_node};
 use dom::validitystate::ValidityState;
 use dom::virtualmethods::VirtualMethods;
+use selectors::states::*;
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::cell::Cell;
diff --git a/components/script/dom/htmlelement.rs b/components/script/dom/htmlelement.rs
index ba2bcdacc16..bb52cbc2402 100644
--- a/components/script/dom/htmlelement.rs
+++ b/components/script/dom/htmlelement.rs
@@ -17,7 +17,7 @@ use dom::bindings::utils::Reflectable;
 use dom::cssstyledeclaration::{CSSModificationAccess, CSSStyleDeclaration};
 use dom::document::Document;
 use dom::domstringmap::DOMStringMap;
-use dom::element::{AttributeMutation, Element, EventState};
+use dom::element::{AttributeMutation, Element};
 use dom::eventtarget::EventTarget;
 use dom::htmlbodyelement::HTMLBodyElement;
 use dom::htmlframesetelement::HTMLFrameSetElement;
@@ -27,6 +27,7 @@ use dom::node::{Node, SEQUENTIALLY_FOCUSABLE};
 use dom::node::{document_from_node, window_from_node};
 use dom::virtualmethods::VirtualMethods;
 use msg::constellation_msg::FocusType;
+use selectors::states::*;
 use std::ascii::AsciiExt;
 use std::borrow::ToOwned;
 use std::default::Default;
@@ -51,10 +52,10 @@ impl PartialEq for HTMLElement {
 impl HTMLElement {
     pub fn new_inherited(tag_name: DOMString, prefix: Option<DOMString>,
                          document: &Document) -> HTMLElement {
-        HTMLElement::new_inherited_with_state(EventState::empty(), tag_name, prefix, document)
+        HTMLElement::new_inherited_with_state(ElementState::empty(), tag_name, prefix, document)
     }
 
-    pub fn new_inherited_with_state(state: EventState, tag_name: DOMString,
+    pub fn new_inherited_with_state(state: ElementState, tag_name: DOMString,
                                     prefix: Option<DOMString>, document: &Document)
                                     -> HTMLElement {
         HTMLElement {
diff --git a/components/script/dom/htmlfieldsetelement.rs b/components/script/dom/htmlfieldsetelement.rs
index 63c614d308f..98c6b86b5f7 100644
--- a/components/script/dom/htmlfieldsetelement.rs
+++ b/components/script/dom/htmlfieldsetelement.rs
@@ -9,7 +9,7 @@ use dom::bindings::codegen::InheritTypes::{ElementTypeId, HTMLElementTypeId, Nod
 use dom::bindings::conversions::Castable;
 use dom::bindings::js::{Root, RootedReference};
 use dom::document::Document;
-use dom::element::{AttributeMutation, Element, IN_ENABLED_STATE};
+use dom::element::{AttributeMutation, Element};
 use dom::htmlcollection::{CollectionFilter, HTMLCollection};
 use dom::htmlelement::HTMLElement;
 use dom::htmlformelement::{FormControl, HTMLFormElement};
@@ -17,6 +17,7 @@ use dom::htmllegendelement::HTMLLegendElement;
 use dom::node::{Node, window_from_node};
 use dom::validitystate::ValidityState;
 use dom::virtualmethods::VirtualMethods;
+use selectors::states::*;
 use util::str::{DOMString, StaticStringVec};
 
 #[dom_struct]
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index baaa2db012d..1adfc56b304 100644
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -15,7 +15,7 @@ use dom::bindings::conversions::Castable;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, LayoutJS, Root, RootedReference};
 use dom::document::Document;
-use dom::element::{AttributeMutation, Element, IN_CHECKED_STATE, IN_ENABLED_STATE, IN_INDETERMINATE_STATE, RawLayoutElementHelpers};
+use dom::element::{AttributeMutation, Element, RawLayoutElementHelpers};
 use dom::event::{Event, EventBubbles, EventCancelable};
 use dom::eventtarget::EventTarget;
 use dom::htmlelement::HTMLElement;
@@ -27,6 +27,7 @@ use dom::node::{Node, NodeDamage};
 use dom::node::{document_from_node, window_from_node};
 use dom::virtualmethods::VirtualMethods;
 use msg::constellation_msg::ConstellationChan;
+use selectors::states::*;
 use std::borrow::ToOwned;
 use std::cell::Cell;
 use string_cache::Atom;
diff --git a/components/script/dom/htmloptgroupelement.rs b/components/script/dom/htmloptgroupelement.rs
index 4d9ec9b6ca9..cb97991b52b 100644
--- a/components/script/dom/htmloptgroupelement.rs
+++ b/components/script/dom/htmloptgroupelement.rs
@@ -8,11 +8,12 @@ use dom::bindings::codegen::Bindings::HTMLOptGroupElementBinding::HTMLOptGroupEl
 use dom::bindings::conversions::Castable;
 use dom::bindings::js::Root;
 use dom::document::Document;
-use dom::element::{AttributeMutation, Element, IN_ENABLED_STATE};
+use dom::element::{AttributeMutation, Element};
 use dom::htmlelement::HTMLElement;
 use dom::htmloptionelement::HTMLOptionElement;
 use dom::node::Node;
 use dom::virtualmethods::VirtualMethods;
+use selectors::states::*;
 use util::str::DOMString;
 
 #[dom_struct]
diff --git a/components/script/dom/htmloptionelement.rs b/components/script/dom/htmloptionelement.rs
index 8c7dea8ac1e..b06406c4df5 100644
--- a/components/script/dom/htmloptionelement.rs
+++ b/components/script/dom/htmloptionelement.rs
@@ -11,13 +11,14 @@ use dom::bindings::conversions::Castable;
 use dom::bindings::js::Root;
 use dom::characterdata::CharacterData;
 use dom::document::Document;
-use dom::element::{AttributeMutation, Element, IN_ENABLED_STATE};
+use dom::element::{AttributeMutation, Element};
 use dom::htmlelement::HTMLElement;
 use dom::htmlscriptelement::HTMLScriptElement;
 use dom::htmlselectelement::HTMLSelectElement;
 use dom::node::Node;
 use dom::text::Text;
 use dom::virtualmethods::VirtualMethods;
+use selectors::states::*;
 use std::cell::Cell;
 use util::str::{DOMString, split_html_space_chars, str_join};
 
diff --git a/components/script/dom/htmlselectelement.rs b/components/script/dom/htmlselectelement.rs
index d20a6451543..c6e90e12c84 100644
--- a/components/script/dom/htmlselectelement.rs
+++ b/components/script/dom/htmlselectelement.rs
@@ -11,7 +11,7 @@ use dom::bindings::codegen::UnionTypes::HTMLOptionElementOrHTMLOptGroupElement;
 use dom::bindings::conversions::Castable;
 use dom::bindings::js::Root;
 use dom::document::Document;
-use dom::element::{AttributeMutation, Element, IN_ENABLED_STATE};
+use dom::element::{AttributeMutation, Element};
 use dom::htmlelement::HTMLElement;
 use dom::htmlfieldsetelement::HTMLFieldSetElement;
 use dom::htmlformelement::{FormControl, HTMLFormElement};
@@ -19,6 +19,7 @@ use dom::htmloptionelement::HTMLOptionElement;
 use dom::node::{Node, window_from_node};
 use dom::validitystate::ValidityState;
 use dom::virtualmethods::VirtualMethods;
+use selectors::states::*;
 use std::borrow::ToOwned;
 use string_cache::Atom;
 use util::str::DOMString;
diff --git a/components/script/dom/htmltextareaelement.rs b/components/script/dom/htmltextareaelement.rs
index 5bbde574e19..b057204245f 100644
--- a/components/script/dom/htmltextareaelement.rs
+++ b/components/script/dom/htmltextareaelement.rs
@@ -13,7 +13,7 @@ use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{LayoutJS, Root};
 use dom::bindings::refcounted::Trusted;
 use dom::document::Document;
-use dom::element::{AttributeMutation, IN_ENABLED_STATE, Element};
+use dom::element::{AttributeMutation, Element};
 use dom::event::{Event, EventBubbles, EventCancelable};
 use dom::eventtarget::EventTarget;
 use dom::htmlelement::HTMLElement;
@@ -26,6 +26,7 @@ use dom::virtualmethods::VirtualMethods;
 use msg::constellation_msg::ConstellationChan;
 use script_task::ScriptTaskEventCategory::InputEvent;
 use script_task::{CommonScriptMsg, Runnable};
+use selectors::states::*;
 use std::borrow::ToOwned;
 use std::cell::Cell;
 use string_cache::Atom;