Auto merge of #19024 - emilio:document, r=KiChjang

Introduce style::dom::TDocument.

The secret plan is introducing a `get_elements_with_id` for use by `querySelector` / `querySelectorAll`.

But this allows also to make some code look a bit nicer.

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components/layout_thread/dom_wrapper.rs

@@ -51,7 +51,7 @@ use script_layout_interface::{OpaqueStyleAndLayoutData, StyleData};
 use script_layout_interface::wrapper_traits::{DangerousThreadSafeLayoutNode, GetLayoutData, LayoutNode};
 use script_layout_interface::wrapper_traits::{PseudoElementType, ThreadSafeLayoutElement, ThreadSafeLayoutNode};
 use selectors::attr::{AttrSelectorOperation, NamespaceConstraint, CaseSensitivity};
-use selectors::matching::{ElementSelectorFlags, MatchingContext, RelevantLinkStatus};
+use selectors::matching::{ElementSelectorFlags, MatchingContext, QuirksMode, RelevantLinkStatus};
 use selectors::matching::VisitedHandlingMode;
 use selectors::sink::Push;
 use servo_arc::{Arc, ArcBorrow};
@@ -69,7 +69,7 @@ use style::computed_values::display;
 use style::context::SharedStyleContext;
 use style::data::ElementData;
 use style::dom::{DomChildren, LayoutIterator, NodeInfo, OpaqueNode};
-use style::dom::{TElement, TNode};
+use style::dom::{TDocument, TElement, TNode};
 use style::element_state::*;
 use style::font_metrics::ServoMetricsProvider;
 use style::properties::{ComputedValues, PropertyDeclarationBlock};
@@ -139,10 +139,6 @@ impl<'ln> ServoLayoutNode<'ln> {
             self.node.type_id_for_layout()
         }
     }
-
-    pub fn as_document(&self) -> Option<ServoLayoutDocument<'ln>> {
-        self.node.downcast().map(ServoLayoutDocument::from_layout_js)
-    }
 }
 
 impl<'ln> NodeInfo for ServoLayoutNode<'ln> {
@@ -158,6 +154,7 @@ impl<'ln> NodeInfo for ServoLayoutNode<'ln> {
 }
 
 impl<'ln> TNode for ServoLayoutNode<'ln> {
+    type ConcreteDocument = ServoLayoutDocument<'ln>;
     type ConcreteElement = ServoLayoutElement<'ln>;
 
     fn parent_node(&self) -> Option<Self> {
@@ -190,6 +187,10 @@ impl<'ln> TNode for ServoLayoutNode<'ln> {
         }
     }
 
+    fn owner_doc(&self) -> Self::ConcreteDocument {
+        ServoLayoutDocument::from_layout_js(unsafe { self.node.owner_doc_for_layout() })
+    }
+
     fn traversal_parent(&self) -> Option<ServoLayoutElement<'ln>> {
         self.parent_element()
     }
@@ -206,6 +207,10 @@ impl<'ln> TNode for ServoLayoutNode<'ln> {
         as_element(self.node)
     }
 
+    fn as_document(&self) -> Option<ServoLayoutDocument<'ln>> {
+        self.node.downcast().map(ServoLayoutDocument::from_layout_js)
+    }
+
     fn can_be_fragmented(&self) -> bool {
         unsafe { self.node.get_flag(CAN_BE_FRAGMENTED) }
     }
@@ -287,11 +292,23 @@ pub struct ServoLayoutDocument<'ld> {
     chain: PhantomData<&'ld ()>,
 }
 
-impl<'ld> ServoLayoutDocument<'ld> {
+impl<'ld> TDocument for ServoLayoutDocument<'ld> {
-    fn as_node(&self) -> ServoLayoutNode<'ld> {
+    type ConcreteNode = ServoLayoutNode<'ld>;
+
+    fn as_node(&self) -> Self::ConcreteNode {
         ServoLayoutNode::from_layout_js(self.document.upcast())
     }
 
+    fn quirks_mode(&self) -> QuirksMode {
+        unsafe { self.document.quirks_mode() }
+    }
+
+    fn is_html_document(&self) -> bool {
+        unsafe { self.document.is_html_document_for_layout() }
+    }
+}
+
+impl<'ld> ServoLayoutDocument<'ld> {
     pub fn root_element(&self) -> Option<ServoLayoutElement<'ld>> {
         self.as_node().dom_children().flat_map(|n| n.as_element()).next()
     }
@@ -773,8 +790,12 @@ impl<'le> ::selectors::Element for ServoLayoutElement<'le> {
 
     fn is_html_element_in_html_document(&self) -> bool {
         unsafe {
-            self.element.html_element_in_html_document_for_layout()
+            if !self.element.is_html_element() {
+                return false;
+            }
         }
+
+        self.as_node().owner_doc().is_html_document()
     }
 }
 

components/script/dom/element.rs

@@ -446,7 +446,7 @@ pub trait LayoutElementHelpers {
     #[allow(unsafe_code)]
     unsafe fn get_rowspan(self) -> u32;
     #[allow(unsafe_code)]
-    unsafe fn html_element_in_html_document_for_layout(&self) -> bool;
+    unsafe fn is_html_element(&self) -> bool;
     fn id_attribute(&self) -> *const Option<Atom>;
     fn style_attribute(&self) -> *const Option<Arc<Locked<PropertyDeclarationBlock>>>;
     fn local_name(&self) -> &LocalName;
@@ -781,11 +781,8 @@ impl LayoutElementHelpers for LayoutDom<Element> {
 
     #[inline]
     #[allow(unsafe_code)]
-    unsafe fn html_element_in_html_document_for_layout(&self) -> bool {
+    unsafe fn is_html_element(&self) -> bool {
-        if (*self.unsafe_get()).namespace != ns!(html) {
+        (*self.unsafe_get()).namespace == ns!(html)
-            return false;
-        }
-        self.upcast::<Node>().owner_doc_for_layout().is_html_document_for_layout()
     }
 
     #[allow(unsafe_code)]

components/style/dom.rs

@@ -22,7 +22,7 @@ use properties::{AnimationRules, ComputedValues, PropertyDeclarationBlock};
 use rule_tree::CascadeLevel;
 use selector_parser::{AttrValue, PseudoClassStringArg, PseudoElement, SelectorImpl};
 use selectors::Element as SelectorsElement;
-use selectors::matching::{ElementSelectorFlags, VisitedHandlingMode};
+use selectors::matching::{ElementSelectorFlags, QuirksMode, VisitedHandlingMode};
 use selectors::sink::Push;
 use servo_arc::{Arc, ArcBorrow};
 use shared_lock::Locked;
@@ -133,12 +133,30 @@ where
     }
 }
 
+/// The `TDocument` trait, to represent a document node.
+pub trait TDocument : Sized + Copy + Clone {
+    /// The concrete `TNode` type.
+    type ConcreteNode: TNode<ConcreteDocument = Self>;
+
+    /// Get this document as a `TNode`.
+    fn as_node(&self) -> Self::ConcreteNode;
+
+    /// Returns whether this document is an HTML document.
+    fn is_html_document(&self) -> bool;
+
+    /// Returns the quirks mode of this document.
+    fn quirks_mode(&self) -> QuirksMode;
+}
+
 /// The `TNode` trait. This is the main generic trait over which the style
 /// system can be implemented.
 pub trait TNode : Sized + Copy + Clone + Debug + NodeInfo + PartialEq {
     /// The concrete `TElement` type.
     type ConcreteElement: TElement<ConcreteNode = Self>;
 
+    /// The concrete `TDocument` type.
+    type ConcreteDocument: TDocument<ConcreteNode = Self>;
+
     /// Get this node's parent node.
     fn parent_node(&self) -> Option<Self>;
 
@@ -154,6 +172,9 @@ pub trait TNode : Sized + Copy + Clone + Debug + NodeInfo + PartialEq {
     /// Get this node's next sibling.
     fn next_sibling(&self) -> Option<Self>;
 
+    /// Get the owner document of this node.
+    fn owner_doc(&self) -> Self::ConcreteDocument;
+
     /// Iterate over the DOM children of a node.
     fn dom_children(&self) -> DomChildren<Self> {
         DomChildren(self.first_child())
@@ -211,6 +232,9 @@ pub trait TNode : Sized + Copy + Clone + Debug + NodeInfo + PartialEq {
     /// Get this node as an element, if it's one.
     fn as_element(&self) -> Option<Self::ConcreteElement>;
 
+    /// Get this node as a document, if it's one.
+    fn as_document(&self) -> Option<Self::ConcreteDocument>;
+
     /// Whether this node can be fragmented. This is used for multicol, and only
     /// for Servo.
     fn can_be_fragmented(&self) -> bool;

components/style/dom_apis.rs

@@ -6,7 +6,7 @@
 //! and Gecko.
 
 use context::QuirksMode;
-use dom::{TElement, TNode};
+use dom::{TDocument, TElement, TNode};
 use invalidation::element::invalidator::{Invalidation, InvalidationProcessor, InvalidationVector};
 use selectors::{Element, NthIndexCache, SelectorList};
 use selectors::matching::{self, MatchingContext, MatchingMode};
@@ -308,7 +308,6 @@ pub fn query_selector<E, Q>(
     root: E::ConcreteNode,
     selector_list: &SelectorList<E::Impl>,
     results: &mut Q::Output,
-    quirks_mode: QuirksMode,
 )
 where
     E: TElement,
@@ -316,6 +315,7 @@ where
 {
     use invalidation::element::invalidator::TreeStyleInvalidator;
 
+    let quirks_mode = root.owner_doc().quirks_mode();
     let fast_result = query_selector_fast::<E, Q>(
         root,
         selector_list,

components/style/gecko/wrapper.rs

@@ -20,7 +20,7 @@ use applicable_declarations::ApplicableDeclarationBlock;
 use atomic_refcell::{AtomicRefCell, AtomicRef, AtomicRefMut};
 use context::{QuirksMode, SharedStyleContext, PostAnimationTasks, UpdateAnimationsTasks};
 use data::ElementData;
-use dom::{LayoutIterator, NodeInfo, OpaqueNode, TElement, TNode};
+use dom::{LayoutIterator, NodeInfo, OpaqueNode, TElement, TDocument, TNode};
 use element_state::{ElementState, DocumentState, NS_DOCUMENT_STATE_WINDOW_INACTIVE};
 use error_reporting::ParseErrorReporter;
 use font_metrics::{FontMetrics, FontMetricsProvider, FontMetricsQueryResult};
@@ -92,6 +92,26 @@ use string_cache::{Atom, Namespace, WeakAtom, WeakNamespace};
 use stylesheets::UrlExtraData;
 use stylist::Stylist;
 
+/// A simple wrapper over `nsIDocument`.
+#[derive(Clone, Copy)]
+pub struct GeckoDocument<'ld>(pub &'ld structs::nsIDocument);
+
+impl<'ld> TDocument for GeckoDocument<'ld> {
+    type ConcreteNode = GeckoNode<'ld>;
+
+    fn as_node(&self) -> Self::ConcreteNode {
+        GeckoNode(&self.0._base)
+    }
+
+    fn is_html_document(&self) -> bool {
+        self.0.mType == structs::root::nsIDocument_Type::eHTML
+    }
+
+    fn quirks_mode(&self) -> QuirksMode {
+        self.0.mCompatMode.into()
+    }
+}
+
 /// A simple wrapper over a non-null Gecko node (`nsINode`) pointer.
 ///
 /// Important: We don't currently refcount the DOM, because the wrapper lifetime
@@ -124,6 +144,13 @@ impl<'ln> fmt::Debug for GeckoNode<'ln> {
 }
 
 impl<'ln> GeckoNode<'ln> {
+    #[inline]
+    fn is_document(&self) -> bool {
+        // This is a DOM constant that isn't going to change.
+        const DOCUMENT_NODE: u16 = 9;
+        self.node_info().mInner.mNodeType == DOCUMENT_NODE
+    }
+
     #[inline]
     fn from_content(content: &'ln nsIContent) -> Self {
         GeckoNode(&content._base)
@@ -153,22 +180,11 @@ impl<'ln> GeckoNode<'ln> {
         (self.0).mBoolFlags
     }
 
-    /// Owner document quirks mode getter.
-    #[inline]
-    pub fn owner_document_quirks_mode(&self) -> QuirksMode {
-        self.owner_doc().mCompatMode.into()
-    }
-
     #[inline]
     fn get_bool_flag(&self, flag: nsINode_BooleanFlag) -> bool {
         self.bool_flags() & (1u32 << flag as u32) != 0
     }
 
-    fn owner_doc(&self) -> &structs::nsIDocument {
-        debug_assert!(!self.node_info().mDocument.is_null());
-        unsafe { &*self.node_info().mDocument }
-    }
-
     /// WARNING: This logic is duplicated in Gecko's FlattenedTreeParentIsParent.
     /// Make sure to mirror any modifications in both places.
     fn flattened_tree_parent_is_parent(&self) -> bool {
@@ -223,6 +239,7 @@ impl<'ln> NodeInfo for GeckoNode<'ln> {
 }
 
 impl<'ln> TNode for GeckoNode<'ln> {
+    type ConcreteDocument = GeckoDocument<'ln>;
     type ConcreteElement = GeckoElement<'ln>;
 
     fn parent_node(&self) -> Option<Self> {
@@ -249,6 +266,12 @@ impl<'ln> TNode for GeckoNode<'ln> {
         unsafe { self.0.mNextSibling.as_ref().map(GeckoNode::from_content) }
     }
 
+    #[inline]
+    fn owner_doc(&self) -> Self::ConcreteDocument {
+        debug_assert!(!self.node_info().mDocument.is_null());
+        GeckoDocument(unsafe { &*self.node_info().mDocument })
+    }
+
     fn traversal_parent(&self) -> Option<GeckoElement<'ln>> {
         self.flattened_tree_parent().and_then(|n| n.as_element())
     }
@@ -271,6 +294,15 @@ impl<'ln> TNode for GeckoNode<'ln> {
         }
     }
 
+    #[inline]
+    fn as_document(&self) -> Option<Self::ConcreteDocument> {
+        if self.is_document() {
+            Some(self.owner_doc())
+        } else {
+            None
+        }
+    }
+
     fn can_be_fragmented(&self) -> bool {
         // FIXME(SimonSapin): Servo uses this to implement CSS multicol / fragmentation
         // Maybe this isn’t useful for Gecko?
@@ -596,7 +628,7 @@ impl<'le> GeckoElement<'le> {
     fn document_state(&self) -> DocumentState {
         let node = self.as_node();
         unsafe {
-            let states = Gecko_DocumentState(node.owner_doc());
+            let states = Gecko_DocumentState(node.owner_doc().0);
             DocumentState::from_bits_truncate(states)
         }
     }
@@ -632,13 +664,7 @@ impl<'le> GeckoElement<'le> {
     #[inline]
     fn get_document_theme(&self) -> DocumentTheme {
         let node = self.as_node();
-        unsafe { Gecko_GetDocumentLWTheme(node.owner_doc()) }
+        unsafe { Gecko_GetDocumentLWTheme(node.owner_doc().0) }
-    }
-
-    /// Owner document quirks mode getter.
-    #[inline]
-    pub fn owner_document_quirks_mode(&self) -> QuirksMode {
-        self.as_node().owner_document_quirks_mode()
     }
 
     /// Only safe to call on the main thread, with exclusive access to the element and
@@ -949,7 +975,7 @@ impl<'le> TElement for GeckoElement<'le> {
     }
 
     fn owner_doc_matches_for_testing(&self, device: &Device) -> bool {
-        self.as_node().owner_doc() as *const structs::nsIDocument ==
+        self.as_node().owner_doc().0 as *const structs::nsIDocument ==
             device.pres_context().mDocument.raw::<structs::nsIDocument>()
     }
 
@@ -1584,7 +1610,7 @@ impl<'le> TElement for GeckoElement<'le> {
             if self.get_local_name().as_ptr() == atom!("th").as_ptr() {
                 hints.push(TH_RULE.clone());
             } else if self.get_local_name().as_ptr() == atom!("table").as_ptr() &&
-                      self.as_node().owner_doc().mCompatMode == structs::nsCompatibility::eCompatibility_NavQuirks {
+                      self.as_node().owner_doc().quirks_mode() == QuirksMode::Quirks {
                 hints.push(TABLE_COLOR_RULE.clone());
             }
         }
@@ -2031,7 +2057,7 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
 
     fn is_html_element_in_html_document(&self) -> bool {
         self.is_html_element() &&
-        self.as_node().owner_doc().mType == structs::root::nsIDocument_Type::eHTML
+        self.as_node().owner_doc().is_html_document()
     }
 
     fn ignores_nth_child_selectors(&self) -> bool {

ports/geckolib/glue.rs

@@ -19,7 +19,7 @@ use style::applicable_declarations::ApplicableDeclarationBlock;
 use style::context::{CascadeInputs, QuirksMode, SharedStyleContext, StyleContext};
 use style::context::ThreadLocalStyleContext;
 use style::data::{ElementStyles, self};
-use style::dom::{ShowSubtreeData, TElement, TNode};
+use style::dom::{ShowSubtreeData, TDocument, TElement, TNode};
 use style::driver;
 use style::element_state::{DocumentState, ElementState};
 use style::error_reporting::{NullReporter, ParseErrorReporter};
@@ -1577,7 +1577,9 @@ pub extern "C" fn Servo_StyleRule_SelectorMatchesElement(rule: RawServoStyleRule
         };
 
         let element = GeckoElement(element);
-        let mut ctx = MatchingContext::new(matching_mode, None, None, element.owner_document_quirks_mode());
+        let quirks_mode = element.as_node().owner_doc().quirks_mode();
+        let mut ctx =
+            MatchingContext::new(matching_mode, None, None, quirks_mode);
         matches_selector(selector, 0, None, &element, &mut ctx, &mut |_, _| {})
     })
 }
@@ -1591,9 +1593,10 @@ pub unsafe extern "C" fn Servo_SelectorList_Closest(
     use style::dom_apis;
 
     let element = GeckoElement(element);
+    let quirks_mode = element.as_node().owner_doc().quirks_mode();
     let selectors = ::selectors::SelectorList::from_ffi(selectors).borrow();
 
-    dom_apis::element_closest(element, &selectors, element.owner_document_quirks_mode())
+    dom_apis::element_closest(element, &selectors, quirks_mode)
         .map_or(ptr::null(), |e| e.0)
 }
 
@@ -1606,11 +1609,12 @@ pub unsafe extern "C" fn Servo_SelectorList_Matches(
     use style::dom_apis;
 
     let element = GeckoElement(element);
+    let quirks_mode = element.as_node().owner_doc().quirks_mode();
     let selectors = ::selectors::SelectorList::from_ffi(selectors).borrow();
     dom_apis::element_matches(
         &element,
         &selectors,
-        element.owner_document_quirks_mode(),
+        quirks_mode,
     )
 }
 
@@ -1629,7 +1633,6 @@ pub unsafe extern "C" fn Servo_SelectorList_QueryFirst(
         node,
         &selectors,
         &mut result,
-        node.owner_document_quirks_mode(),
     );
 
     result.map_or(ptr::null(), |e| e.0)
@@ -1653,7 +1656,6 @@ pub unsafe extern "C" fn Servo_SelectorList_QueryAll(
         node,
         &selectors,
         &mut result,
-        node.owner_document_quirks_mode(),
     );
 
     if !result.is_empty() {