--- a/servo/components/style/context.rs
+++ b/servo/components/style/context.rs
@@ -2,29 +2,32 @@
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
//! The context within which style is calculated.
#[cfg(feature = "servo")] use animation::Animation;
use animation::PropertyAnimation;
use app_units::Au;
+use arrayvec::ArrayVec;
use bloom::StyleBloom;
use cache::LRUCache;
use data::ElementData;
use dom::{OpaqueNode, TNode, TElement, SendElement};
use error_reporting::ParseErrorReporter;
use euclid::Size2D;
use fnv::FnvHashMap;
use font_metrics::FontMetricsProvider;
#[cfg(feature = "gecko")] use gecko_bindings::structs;
#[cfg(feature = "servo")] use parking_lot::RwLock;
-#[cfg(feature = "gecko")] use properties::ComputedValues;
-use selector_parser::SnapshotMap;
-use selectors::matching::ElementSelectorFlags;
+use properties::ComputedValues;
+use properties::longhands::display::computed_value as display;
+use rule_tree::StrongRuleNode;
+use selector_parser::{EAGER_PSEUDO_COUNT, PseudoElement, SnapshotMap};
+use selectors::matching::{ElementSelectorFlags, VisitedHandlingMode};
use shared_lock::StylesheetGuards;
use sharing::{ValidationData, StyleSharingCandidateCache};
use std::fmt;
use std::ops::Add;
#[cfg(feature = "servo")] use std::sync::Mutex;
#[cfg(feature = "servo")] use std::sync::mpsc::Sender;
use stylearc::Arc;
use stylist::Stylist;
@@ -136,16 +139,347 @@ pub struct SharedStyleContext<'a> {
impl<'a> SharedStyleContext<'a> {
/// Return a suitable viewport size in order to be used for viewport units.
pub fn viewport_size(&self) -> Size2D<Au> {
self.stylist.device().au_viewport_size()
}
}
+/// The structure that represents the result of style computation. This is
+/// effectively a tuple of rules and computed values, that is, the rule node,
+/// and the result of computing that rule node's rules, the `ComputedValues`.
+#[derive(Clone)]
+pub struct ComputedStyle {
+ /// The rule node representing the ordered list of rules matched for this
+ /// node.
+ pub rules: StrongRuleNode,
+
+ /// The computed values for each property obtained by cascading the
+ /// matched rules. This can only be none during a transient interval of
+ /// the styling algorithm, and callers can safely unwrap it.
+ pub values: Option<Arc<ComputedValues>>,
+
+ /// The rule node representing the ordered list of rules matched for this
+ /// node if visited, only computed if there's a relevant link for this
+ /// element. A element's "relevant link" is the element being matched if it
+ /// is a link or the nearest ancestor link.
+ visited_rules: Option<StrongRuleNode>,
+
+ /// The element's computed values if visited, only computed if there's a
+ /// relevant link for this element. A element's "relevant link" is the
+ /// element being matched if it is a link or the nearest ancestor link.
+ ///
+ /// We also store a reference to this inside the regular ComputedValues to
+ /// avoid refactoring all APIs to become aware of multiple ComputedValues
+ /// objects.
+ visited_values: Option<Arc<ComputedValues>>,
+}
+
+impl ComputedStyle {
+ /// Trivially construct a new `ComputedStyle`.
+ pub fn new(rules: StrongRuleNode, values: Arc<ComputedValues>) -> Self {
+ ComputedStyle {
+ rules: rules,
+ values: Some(values),
+ visited_rules: None,
+ visited_values: None,
+ }
+ }
+
+ /// Constructs a partial ComputedStyle, whose ComputedVaues will be filled
+ /// in later.
+ pub fn new_partial(rules: StrongRuleNode) -> Self {
+ ComputedStyle {
+ rules: rules,
+ values: None,
+ visited_rules: None,
+ visited_values: None,
+ }
+ }
+
+ /// Returns a reference to the ComputedValues. The values can only be null during
+ /// the styling algorithm, so this is safe to call elsewhere.
+ pub fn values(&self) -> &Arc<ComputedValues> {
+ self.values.as_ref().unwrap()
+ }
+
+ /// Whether there are any visited rules.
+ pub fn has_visited_rules(&self) -> bool {
+ self.visited_rules.is_some()
+ }
+
+ /// Gets a reference to the visited rule node, if any.
+ pub fn get_visited_rules(&self) -> Option<&StrongRuleNode> {
+ self.visited_rules.as_ref()
+ }
+
+ /// Gets a mutable reference to the visited rule node, if any.
+ pub fn get_visited_rules_mut(&mut self) -> Option<&mut StrongRuleNode> {
+ self.visited_rules.as_mut()
+ }
+
+ /// Gets a reference to the visited rule node. Panic if the element does not
+ /// have visited rule node.
+ pub fn visited_rules(&self) -> &StrongRuleNode {
+ self.get_visited_rules().unwrap()
+ }
+
+ /// Sets the visited rule node, and returns whether it changed.
+ pub fn set_visited_rules(&mut self, rules: StrongRuleNode) -> bool {
+ if let Some(ref old_rules) = self.visited_rules {
+ if *old_rules == rules {
+ return false
+ }
+ }
+ self.visited_rules = Some(rules);
+ true
+ }
+
+ /// Takes the visited rule node.
+ pub fn take_visited_rules(&mut self) -> Option<StrongRuleNode> {
+ self.visited_rules.take()
+ }
+
+ /// Gets a reference to the visited computed values. Panic if the element
+ /// does not have visited computed values.
+ pub fn visited_values(&self) -> &Arc<ComputedValues> {
+ self.visited_values.as_ref().unwrap()
+ }
+
+ /// Sets the visited computed values.
+ pub fn set_visited_values(&mut self, values: Arc<ComputedValues>) {
+ self.visited_values = Some(values);
+ }
+
+ /// Take the visited computed values.
+ pub fn take_visited_values(&mut self) -> Option<Arc<ComputedValues>> {
+ self.visited_values.take()
+ }
+
+ /// Clone the visited computed values Arc. Used to store a reference to the
+ /// visited values inside the regular values.
+ pub fn clone_visited_values(&self) -> Option<Arc<ComputedValues>> {
+ self.visited_values.clone()
+ }
+}
+
+// We manually implement Debug for ComputedStyle so that we can avoid the
+// verbose stringification of ComputedValues for normal logging.
+impl fmt::Debug for ComputedStyle {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ write!(f, "ComputedStyle {{ rules: {:?}, values: {{..}} }}", self.rules)
+ }
+}
+
+/// A list of styles for eagerly-cascaded pseudo-elements. Lazily-allocated.
+#[derive(Clone, Debug)]
+pub struct EagerPseudoStyles(Option<Box<[Option<ComputedStyle>]>>);
+
+impl EagerPseudoStyles {
+ /// Returns whether there are any pseudo styles.
+ pub fn is_empty(&self) -> bool {
+ self.0.is_none()
+ }
+
+ /// Returns a reference to the style for a given eager pseudo, if it exists.
+ pub fn get(&self, pseudo: &PseudoElement) -> Option<&ComputedStyle> {
+ debug_assert!(pseudo.is_eager());
+ self.0.as_ref().and_then(|p| p[pseudo.eager_index()].as_ref())
+ }
+
+ /// Returns a mutable reference to the style for a given eager pseudo, if it exists.
+ pub fn get_mut(&mut self, pseudo: &PseudoElement) -> Option<&mut ComputedStyle> {
+ debug_assert!(pseudo.is_eager());
+ self.0.as_mut().and_then(|p| p[pseudo.eager_index()].as_mut())
+ }
+
+ /// Returns true if the EagerPseudoStyles has a ComputedStyle for |pseudo|.
+ pub fn has(&self, pseudo: &PseudoElement) -> bool {
+ self.get(pseudo).is_some()
+ }
+
+ /// Inserts a pseudo-element. The pseudo-element must not already exist.
+ pub fn insert(&mut self, pseudo: &PseudoElement, style: ComputedStyle) {
+ debug_assert!(!self.has(pseudo));
+ if self.0.is_none() {
+ self.0 = Some(vec![None; EAGER_PSEUDO_COUNT].into_boxed_slice());
+ }
+ self.0.as_mut().unwrap()[pseudo.eager_index()] = Some(style);
+ }
+
+ /// Removes a pseudo-element style if it exists, and returns it.
+ fn take(&mut self, pseudo: &PseudoElement) -> Option<ComputedStyle> {
+ let result = match self.0.as_mut() {
+ None => return None,
+ Some(arr) => arr[pseudo.eager_index()].take(),
+ };
+ let empty = self.0.as_ref().unwrap().iter().all(|x| x.is_none());
+ if empty {
+ self.0 = None;
+ }
+ result
+ }
+
+ /// Returns a list of the pseudo-elements.
+ pub fn keys(&self) -> ArrayVec<[PseudoElement; EAGER_PSEUDO_COUNT]> {
+ let mut v = ArrayVec::new();
+ if let Some(ref arr) = self.0 {
+ for i in 0..EAGER_PSEUDO_COUNT {
+ if arr[i].is_some() {
+ v.push(PseudoElement::from_eager_index(i));
+ }
+ }
+ }
+ v
+ }
+
+ /// Adds the unvisited rule node for a given pseudo-element, which may or
+ /// may not exist.
+ ///
+ /// Returns true if the pseudo-element is new.
+ fn add_unvisited_rules(&mut self,
+ pseudo: &PseudoElement,
+ rules: StrongRuleNode)
+ -> bool {
+ if let Some(mut style) = self.get_mut(pseudo) {
+ style.rules = rules;
+ return false
+ }
+ self.insert(pseudo, ComputedStyle::new_partial(rules));
+ true
+ }
+
+ /// Remove the unvisited rule node for a given pseudo-element, which may or
+ /// may not exist. Since removing the rule node implies we don't need any
+ /// other data for the pseudo, take the entire pseudo if found.
+ ///
+ /// Returns true if the pseudo-element was removed.
+ fn remove_unvisited_rules(&mut self, pseudo: &PseudoElement) -> bool {
+ self.take(pseudo).is_some()
+ }
+
+ /// Adds the visited rule node for a given pseudo-element. It is assumed to
+ /// already exist because unvisited styles should have been added first.
+ ///
+ /// Returns true if the pseudo-element is new. (Always false, but returns a
+ /// bool for parity with `add_unvisited_rules`.)
+ fn add_visited_rules(&mut self,
+ pseudo: &PseudoElement,
+ rules: StrongRuleNode)
+ -> bool {
+ debug_assert!(self.has(pseudo));
+ let mut style = self.get_mut(pseudo).unwrap();
+ style.set_visited_rules(rules);
+ false
+ }
+
+ /// Remove the visited rule node for a given pseudo-element, which may or
+ /// may not exist.
+ ///
+ /// Returns true if the psuedo-element was removed. (Always false, but
+ /// returns a bool for parity with `remove_unvisited_rules`.)
+ fn remove_visited_rules(&mut self, pseudo: &PseudoElement) -> bool {
+ if let Some(mut style) = self.get_mut(pseudo) {
+ style.take_visited_rules();
+ }
+ false
+ }
+
+ /// Adds a rule node for a given pseudo-element, which may or may not exist.
+ /// The type of rule node depends on the visited mode.
+ ///
+ /// Returns true if the pseudo-element is new.
+ pub fn add_rules(&mut self,
+ pseudo: &PseudoElement,
+ visited_handling: VisitedHandlingMode,
+ rules: StrongRuleNode)
+ -> bool {
+ match visited_handling {
+ VisitedHandlingMode::AllLinksVisitedAndUnvisited => {
+ unreachable!("We should never try to selector match with \
+ AllLinksVisitedAndUnvisited");
+ },
+ VisitedHandlingMode::AllLinksUnvisited => {
+ self.add_unvisited_rules(&pseudo, rules)
+ },
+ VisitedHandlingMode::RelevantLinkVisited => {
+ self.add_visited_rules(&pseudo, rules)
+ },
+ }
+ }
+
+ /// Removes a rule node for a given pseudo-element, which may or may not
+ /// exist. The type of rule node depends on the visited mode.
+ ///
+ /// Returns true if the psuedo-element was removed.
+ pub fn remove_rules(&mut self,
+ pseudo: &PseudoElement,
+ visited_handling: VisitedHandlingMode)
+ -> bool {
+ match visited_handling {
+ VisitedHandlingMode::AllLinksVisitedAndUnvisited => {
+ unreachable!("We should never try to selector match with \
+ AllLinksVisitedAndUnvisited");
+ },
+ VisitedHandlingMode::AllLinksUnvisited => {
+ self.remove_unvisited_rules(&pseudo)
+ },
+ VisitedHandlingMode::RelevantLinkVisited => {
+ self.remove_visited_rules(&pseudo)
+ },
+ }
+ }
+
+ /// Returns whether this EagerPseudoStyles has the same set of
+ /// pseudos as the given one.
+ pub fn has_same_pseudos_as(&self, other: &EagerPseudoStyles) -> bool {
+ // We could probably just compare self.keys() to other.keys(), but that
+ // seems like it'll involve a bunch more moving stuff around and
+ // whatnot.
+ match (&self.0, &other.0) {
+ (&Some(ref our_arr), &Some(ref other_arr)) => {
+ for i in 0..EAGER_PSEUDO_COUNT {
+ if our_arr[i].is_some() != other_arr[i].is_some() {
+ return false
+ }
+ }
+ true
+ },
+ (&None, &None) => true,
+ _ => false,
+ }
+ }
+}
+
+/// The styles associated with a node, including the styles for any
+/// pseudo-elements.
+#[derive(Clone, Debug)]
+pub struct ElementStyles {
+ /// The element's style.
+ pub primary: ComputedStyle,
+ /// A list of the styles for the element's eagerly-cascaded pseudo-elements.
+ pub pseudos: EagerPseudoStyles,
+}
+
+impl ElementStyles {
+ /// Trivially construct a new `ElementStyles`.
+ pub fn new(primary: ComputedStyle) -> Self {
+ ElementStyles {
+ primary: primary,
+ pseudos: EagerPseudoStyles(None),
+ }
+ }
+
+ /// Whether this element `display` value is `none`.
+ pub fn is_display_none(&self) -> bool {
+ self.primary.values().get_box().clone_display() == display::T::none
+ }
+}
+
/// Information about the current element being processed. We group this
/// together into a single struct within ThreadLocalStyleContext so that we can
/// instantiate and destroy it easily at the beginning and end of element
/// processing.
pub struct CurrentElementInfo {
/// The element being processed. Currently we use an OpaqueNode since we
/// only use this for identity checks, but we could use SendElement if there
/// were a good reason to.