mirror of
https://github.com/servo/servo.git
synced 2025-10-09 13:09:25 +01:00
f9205440b5
We can have cousins in the cache whose parent doesn't match ours, and other cousins whose parent does. When we encounter one of the former, that's not a reason to stop lookin for the latter. Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1369620
1473 lines
64 KiB
Rust
1473 lines
64 KiB
Rust
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* 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/. */
|
|
|
|
//! High-level interface to CSS selector matching.
|
|
|
|
#![allow(unsafe_code)]
|
|
#![deny(missing_docs)]
|
|
|
|
use cascade_info::CascadeInfo;
|
|
use context::{SelectorFlagsMap, SharedStyleContext, StyleContext};
|
|
use data::{ComputedStyle, ElementData, RestyleData};
|
|
use dom::{TElement, TNode};
|
|
use font_metrics::FontMetricsProvider;
|
|
use log::LogLevel::Trace;
|
|
use properties::{ALLOW_SET_ROOT_FONT_SIZE, SKIP_ROOT_AND_ITEM_BASED_DISPLAY_FIXUP};
|
|
use properties::{AnimationRules, CascadeFlags, ComputedValues};
|
|
use properties::{VISITED_DEPENDENT_ONLY, cascade};
|
|
use properties::longhands::display::computed_value as display;
|
|
use restyle_hints::{RESTYLE_CSS_ANIMATIONS, RESTYLE_CSS_TRANSITIONS, RestyleReplacements};
|
|
use restyle_hints::{RESTYLE_STYLE_ATTRIBUTE, RESTYLE_SMIL};
|
|
use rule_tree::{CascadeLevel, StrongRuleNode};
|
|
use selector_parser::{PseudoElement, RestyleDamage, SelectorImpl};
|
|
use selectors::matching::{ElementSelectorFlags, MatchingContext, MatchingMode, StyleRelations};
|
|
use selectors::matching::{VisitedHandlingMode, AFFECTED_BY_PSEUDO_ELEMENTS};
|
|
use sharing::StyleSharingBehavior;
|
|
use stylearc::Arc;
|
|
use stylist::{ApplicableDeclarationList, RuleInclusion};
|
|
|
|
/// The way a style should be inherited.
|
|
enum InheritMode {
|
|
/// Inherit from the parent element, as normal CSS dictates, _or_ from the
|
|
/// closest non-Native Anonymous element in case this is Native Anonymous
|
|
/// Content.
|
|
Normal,
|
|
/// Inherit from the primary style, this is used while computing eager
|
|
/// pseudos, like ::before and ::after when we're traversing the parent.
|
|
FromPrimaryStyle,
|
|
}
|
|
|
|
/// Represents the result of comparing an element's old and new style.
|
|
pub struct StyleDifference {
|
|
/// The resulting damage.
|
|
pub damage: RestyleDamage,
|
|
|
|
/// Whether any styles changed.
|
|
pub change: StyleChange,
|
|
}
|
|
|
|
impl StyleDifference {
|
|
/// Creates a new `StyleDifference`.
|
|
pub fn new(damage: RestyleDamage, change: StyleChange) -> Self {
|
|
StyleDifference {
|
|
change: change,
|
|
damage: damage,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Represents whether or not the style of an element has changed.
|
|
#[derive(Copy, Clone)]
|
|
pub enum StyleChange {
|
|
/// The style hasn't changed.
|
|
Unchanged,
|
|
/// The style has changed.
|
|
Changed,
|
|
}
|
|
|
|
/// Whether or not newly computed values for an element need to be cascade
|
|
/// to children.
|
|
pub enum ChildCascadeRequirement {
|
|
/// Old and new computed values were the same, or we otherwise know that
|
|
/// we won't bother recomputing style for children, so we can skip cascading
|
|
/// the new values into child elements.
|
|
CanSkipCascade,
|
|
/// Old and new computed values were different, so we must cascade the
|
|
/// new values to children.
|
|
///
|
|
/// FIXME(heycam) Although this is "must" cascade, in the future we should
|
|
/// track whether child elements rely specifically on inheriting particular
|
|
/// property values. When we do that, we can treat `MustCascadeChildren` as
|
|
/// "must cascade unless we know that changes to these properties can be
|
|
/// ignored".
|
|
MustCascadeChildren,
|
|
/// The same as `MustCascadeChildren`, but for the entire subtree. This is
|
|
/// used to handle root font-size updates needing to recascade the whole
|
|
/// document.
|
|
MustCascadeDescendants,
|
|
}
|
|
|
|
impl From<StyleChange> for ChildCascadeRequirement {
|
|
fn from(change: StyleChange) -> ChildCascadeRequirement {
|
|
match change {
|
|
StyleChange::Unchanged => ChildCascadeRequirement::CanSkipCascade,
|
|
StyleChange::Changed => ChildCascadeRequirement::MustCascadeChildren,
|
|
}
|
|
}
|
|
}
|
|
|
|
bitflags! {
|
|
/// Flags that represent the result of replace_rules.
|
|
pub flags RulesChanged: u8 {
|
|
/// Normal rules are changed.
|
|
const NORMAL_RULES_CHANGED = 0x01,
|
|
/// Important rules are changed.
|
|
const IMPORTANT_RULES_CHANGED = 0x02,
|
|
}
|
|
}
|
|
|
|
impl RulesChanged {
|
|
/// Return true if there are any normal rules changed.
|
|
#[inline]
|
|
pub fn normal_rules_changed(&self) -> bool {
|
|
self.contains(NORMAL_RULES_CHANGED)
|
|
}
|
|
|
|
/// Return true if there are any important rules changed.
|
|
#[inline]
|
|
pub fn important_rules_changed(&self) -> bool {
|
|
self.contains(IMPORTANT_RULES_CHANGED)
|
|
}
|
|
}
|
|
|
|
/// Determines which styles are being cascaded currently.
|
|
#[derive(PartialEq, Eq, Copy, Clone, Debug)]
|
|
pub enum CascadeVisitedMode {
|
|
/// Cascade the regular, unvisited styles.
|
|
Unvisited,
|
|
/// Cascade the styles used when an element's relevant link is visited. A
|
|
/// "relevant link" is the element being matched if it is a link or the
|
|
/// nearest ancestor link.
|
|
Visited,
|
|
}
|
|
|
|
/// Various helper methods to ease navigating the style storage locations
|
|
/// depending on the current cascade mode.
|
|
impl CascadeVisitedMode {
|
|
/// Returns whether there is a rule node based on the cascade mode.
|
|
fn has_rules(&self, style: &ComputedStyle) -> bool {
|
|
match *self {
|
|
CascadeVisitedMode::Unvisited => true,
|
|
CascadeVisitedMode::Visited => style.has_visited_rules(),
|
|
}
|
|
}
|
|
|
|
/// Returns the rule node based on the cascade mode.
|
|
fn rules<'a>(&self, style: &'a ComputedStyle) -> &'a StrongRuleNode {
|
|
match *self {
|
|
CascadeVisitedMode::Unvisited => &style.rules,
|
|
CascadeVisitedMode::Visited => style.visited_rules(),
|
|
}
|
|
}
|
|
|
|
/// Returns a mutable rules node based on the cascade mode, if any.
|
|
fn get_rules_mut<'a>(&self, style: &'a mut ComputedStyle) -> Option<&'a mut StrongRuleNode> {
|
|
match *self {
|
|
CascadeVisitedMode::Unvisited => Some(&mut style.rules),
|
|
CascadeVisitedMode::Visited => style.get_visited_rules_mut(),
|
|
}
|
|
}
|
|
|
|
/// Returns the computed values based on the cascade mode. In visited mode,
|
|
/// visited values are only returned if they already exist. If they don't,
|
|
/// we fallback to the regular, unvisited styles.
|
|
fn values<'a>(&self, style: &'a ComputedStyle) -> &'a Arc<ComputedValues> {
|
|
let mut values = style.values();
|
|
|
|
if *self == CascadeVisitedMode::Visited && values.get_visited_style().is_some() {
|
|
values = values.visited_style();
|
|
}
|
|
|
|
values
|
|
}
|
|
|
|
/// Set the computed values based on the cascade mode.
|
|
fn set_values(&self, style: &mut ComputedStyle, values: Arc<ComputedValues>) {
|
|
match *self {
|
|
CascadeVisitedMode::Unvisited => style.values = Some(values),
|
|
CascadeVisitedMode::Visited => style.set_visited_values(values),
|
|
}
|
|
}
|
|
|
|
/// Take the computed values based on the cascade mode.
|
|
fn take_values(&self, style: &mut ComputedStyle) -> Option<Arc<ComputedValues>> {
|
|
match *self {
|
|
CascadeVisitedMode::Unvisited => style.values.take(),
|
|
CascadeVisitedMode::Visited => style.take_visited_values(),
|
|
}
|
|
}
|
|
|
|
/// Returns whether there might be visited values that should be inserted
|
|
/// within the regular computed values based on the cascade mode.
|
|
fn visited_values_for_insertion(&self) -> bool {
|
|
*self == CascadeVisitedMode::Unvisited
|
|
}
|
|
|
|
/// Returns whether animations should be processed based on the cascade
|
|
/// mode. At the moment, it appears we don't need to support animating
|
|
/// visited styles.
|
|
fn should_process_animations(&self) -> bool {
|
|
*self == CascadeVisitedMode::Unvisited
|
|
}
|
|
|
|
/// Returns whether we should accumulate restyle damage based on the cascade
|
|
/// mode. At the moment, it appears we don't need to do so for visited
|
|
/// styles. TODO: Verify this is correct as part of
|
|
/// https://bugzilla.mozilla.org/show_bug.cgi?id=1364484.
|
|
fn should_accumulate_damage(&self) -> bool {
|
|
*self == CascadeVisitedMode::Unvisited
|
|
}
|
|
|
|
/// Returns whether the cascade should filter to only visited dependent
|
|
/// properties based on the cascade mode.
|
|
fn visited_dependent_only(&self) -> bool {
|
|
*self == CascadeVisitedMode::Visited
|
|
}
|
|
}
|
|
|
|
trait PrivateMatchMethods: TElement {
|
|
/// Returns the closest parent element that doesn't have a display: contents
|
|
/// style (and thus generates a box).
|
|
///
|
|
/// This is needed to correctly handle blockification of flex and grid
|
|
/// items.
|
|
///
|
|
/// Returns itself if the element has no parent. In practice this doesn't
|
|
/// happen because the root element is blockified per spec, but it could
|
|
/// happen if we decide to not blockify for roots of disconnected subtrees,
|
|
/// which is a kind of dubious beahavior.
|
|
fn layout_parent(&self) -> Self {
|
|
let mut current = self.clone();
|
|
loop {
|
|
current = match current.parent_element() {
|
|
Some(el) => el,
|
|
None => return current,
|
|
};
|
|
|
|
let is_display_contents =
|
|
current.borrow_data().unwrap().styles().primary.values().is_display_contents();
|
|
|
|
if !is_display_contents {
|
|
return current;
|
|
}
|
|
}
|
|
}
|
|
|
|
fn cascade_with_rules(&self,
|
|
shared_context: &SharedStyleContext,
|
|
font_metrics_provider: &FontMetricsProvider,
|
|
rule_node: &StrongRuleNode,
|
|
primary_style: &ComputedStyle,
|
|
inherit_mode: InheritMode,
|
|
cascade_visited: CascadeVisitedMode,
|
|
visited_values_to_insert: Option<Arc<ComputedValues>>)
|
|
-> Arc<ComputedValues> {
|
|
let mut cascade_info = CascadeInfo::new();
|
|
let mut cascade_flags = CascadeFlags::empty();
|
|
if self.skip_root_and_item_based_display_fixup() {
|
|
cascade_flags.insert(SKIP_ROOT_AND_ITEM_BASED_DISPLAY_FIXUP)
|
|
}
|
|
if cascade_visited.visited_dependent_only() {
|
|
cascade_flags.insert(VISITED_DEPENDENT_ONLY);
|
|
}
|
|
if !self.is_native_anonymous() {
|
|
cascade_flags.insert(ALLOW_SET_ROOT_FONT_SIZE);
|
|
}
|
|
|
|
// Grab the inherited values.
|
|
let parent_el;
|
|
let parent_data;
|
|
let style_to_inherit_from = match inherit_mode {
|
|
InheritMode::Normal => {
|
|
parent_el = self.inheritance_parent();
|
|
parent_data = parent_el.as_ref().and_then(|e| e.borrow_data());
|
|
let parent_style = parent_data.as_ref().map(|d| {
|
|
// Sometimes Gecko eagerly styles things without processing
|
|
// pending restyles first. In general we'd like to avoid this,
|
|
// but there can be good reasons (for example, needing to
|
|
// construct a frame for some small piece of newly-added
|
|
// content in order to do something specific with that frame,
|
|
// but not wanting to flush all of layout).
|
|
debug_assert!(cfg!(feature = "gecko") ||
|
|
parent_el.unwrap().has_current_styles(d));
|
|
&d.styles().primary
|
|
});
|
|
parent_style.map(|s| cascade_visited.values(s))
|
|
}
|
|
InheritMode::FromPrimaryStyle => {
|
|
parent_el = Some(self.clone());
|
|
Some(cascade_visited.values(primary_style))
|
|
}
|
|
};
|
|
|
|
let mut layout_parent_el = parent_el.clone();
|
|
let layout_parent_data;
|
|
let mut layout_parent_style = style_to_inherit_from;
|
|
if style_to_inherit_from.map_or(false, |s| s.is_display_contents()) {
|
|
layout_parent_el = Some(layout_parent_el.unwrap().layout_parent());
|
|
layout_parent_data = layout_parent_el.as_ref().unwrap().borrow_data().unwrap();
|
|
layout_parent_style = Some(cascade_visited.values(&layout_parent_data.styles().primary));
|
|
}
|
|
|
|
let style_to_inherit_from = style_to_inherit_from.map(|x| &**x);
|
|
let layout_parent_style = layout_parent_style.map(|x| &**x);
|
|
|
|
// Propagate the "can be fragmented" bit. It would be nice to
|
|
// encapsulate this better.
|
|
//
|
|
// Note that this is technically not needed for pseudos since we already
|
|
// do that when we resolve the non-pseudo style, but it doesn't hurt
|
|
// anyway.
|
|
//
|
|
// TODO(emilio): This is servo-only, move somewhere else?
|
|
if let Some(ref p) = layout_parent_style {
|
|
let can_be_fragmented =
|
|
p.is_multicol() ||
|
|
layout_parent_el.as_ref().unwrap().as_node().can_be_fragmented();
|
|
unsafe { self.as_node().set_can_be_fragmented(can_be_fragmented); }
|
|
}
|
|
|
|
// Invoke the cascade algorithm.
|
|
let values =
|
|
Arc::new(cascade(shared_context.stylist.device(),
|
|
rule_node,
|
|
&shared_context.guards,
|
|
style_to_inherit_from,
|
|
layout_parent_style,
|
|
visited_values_to_insert,
|
|
Some(&mut cascade_info),
|
|
&*shared_context.error_reporter,
|
|
font_metrics_provider,
|
|
cascade_flags,
|
|
shared_context.quirks_mode));
|
|
|
|
cascade_info.finish(&self.as_node());
|
|
values
|
|
}
|
|
|
|
fn cascade_internal(&self,
|
|
context: &StyleContext<Self>,
|
|
primary_style: &ComputedStyle,
|
|
eager_pseudo_style: Option<&ComputedStyle>,
|
|
cascade_visited: CascadeVisitedMode)
|
|
-> Arc<ComputedValues> {
|
|
if let Some(pseudo) = self.implemented_pseudo_element() {
|
|
debug_assert!(eager_pseudo_style.is_none());
|
|
|
|
// This is an element-backed pseudo, just grab the styles from the
|
|
// parent if it's eager, and recascade otherwise.
|
|
//
|
|
// We also recascade if the eager pseudo-style has any animation
|
|
// rules, because we don't cascade those during the eager traversal.
|
|
//
|
|
// We could make that a bit better if the complexity cost is not too
|
|
// big, but given further restyles are posted directly to
|
|
// pseudo-elements, it doesn't seem worth the effort at a glance.
|
|
//
|
|
// For the same reason as described in match_primary, if we are
|
|
// computing default styles, we aren't guaranteed the parent
|
|
// will have eagerly computed our styles, so we just handled it
|
|
// below like a lazy pseudo.
|
|
let only_default_rules = context.shared.traversal_flags.for_default_styles();
|
|
if pseudo.is_eager() && !only_default_rules {
|
|
debug_assert!(pseudo.is_before_or_after());
|
|
let parent = self.parent_element().unwrap();
|
|
if !parent.may_have_animations() ||
|
|
primary_style.rules.get_animation_rules().is_empty() {
|
|
let parent_data = parent.borrow_data().unwrap();
|
|
let pseudo_style =
|
|
parent_data.styles().pseudos.get(&pseudo).unwrap();
|
|
let values = cascade_visited.values(pseudo_style);
|
|
return values.clone()
|
|
}
|
|
}
|
|
}
|
|
|
|
// Find possible visited computed styles to insert within the regular
|
|
// computed values we are about to create.
|
|
let visited_values_to_insert = if cascade_visited.visited_values_for_insertion() {
|
|
match eager_pseudo_style {
|
|
Some(ref s) => s.clone_visited_values(),
|
|
None => primary_style.clone_visited_values(),
|
|
}
|
|
} else {
|
|
None
|
|
};
|
|
|
|
// Grab the rule node.
|
|
let style = eager_pseudo_style.unwrap_or(primary_style);
|
|
let rule_node = cascade_visited.rules(style);
|
|
let inherit_mode = if eager_pseudo_style.is_some() {
|
|
InheritMode::FromPrimaryStyle
|
|
} else {
|
|
InheritMode::Normal
|
|
};
|
|
|
|
self.cascade_with_rules(context.shared,
|
|
&context.thread_local.font_metrics_provider,
|
|
rule_node,
|
|
primary_style,
|
|
inherit_mode,
|
|
cascade_visited,
|
|
visited_values_to_insert)
|
|
}
|
|
|
|
/// Computes values and damage for the primary style of an element, setting
|
|
/// them on the ElementData.
|
|
fn cascade_primary(&self,
|
|
context: &mut StyleContext<Self>,
|
|
data: &mut ElementData,
|
|
important_rules_changed: bool,
|
|
cascade_visited: CascadeVisitedMode)
|
|
-> ChildCascadeRequirement {
|
|
debug!("Cascade primary for {:?}, visited: {:?}", self, cascade_visited);
|
|
|
|
// Collect some values.
|
|
let (mut styles, restyle) = data.styles_and_restyle_mut();
|
|
let mut primary_style = &mut styles.primary;
|
|
// If there was no relevant link, we won't have any visited rules, so
|
|
// there may not be anything do for the visited case. This early return
|
|
// is especially important for the `cascade_primary_and_pseudos` path
|
|
// since we rely on the state of some previous matching run.
|
|
if !cascade_visited.has_rules(primary_style) {
|
|
return ChildCascadeRequirement::CanSkipCascade
|
|
}
|
|
let mut old_values = cascade_visited.take_values(primary_style);
|
|
|
|
// Compute the new values.
|
|
let mut new_values = self.cascade_internal(context,
|
|
primary_style,
|
|
None,
|
|
cascade_visited);
|
|
|
|
// NB: Animations for pseudo-elements in Gecko are handled while
|
|
// traversing the pseudo-elements themselves.
|
|
if !context.shared.traversal_flags.for_animation_only() &&
|
|
cascade_visited.should_process_animations() {
|
|
self.process_animations(context,
|
|
&mut old_values,
|
|
&mut new_values,
|
|
primary_style,
|
|
important_rules_changed);
|
|
}
|
|
|
|
let mut child_cascade_requirement =
|
|
ChildCascadeRequirement::CanSkipCascade;
|
|
if cascade_visited.should_accumulate_damage() {
|
|
child_cascade_requirement =
|
|
self.accumulate_damage(&context.shared,
|
|
restyle,
|
|
old_values.as_ref().map(|v| v.as_ref()),
|
|
&new_values,
|
|
None);
|
|
|
|
// Handle root font-size changes.
|
|
if self.is_root() && !self.is_native_anonymous() {
|
|
// The new root font-size has already been updated on the Device
|
|
// in properties::apply_declarations.
|
|
let device = context.shared.stylist.device();
|
|
let new_font_size = new_values.get_font().clone_font_size();
|
|
|
|
// If the root font-size changed since last time, and something
|
|
// in the document did use rem units, ensure we recascade the
|
|
// entire tree.
|
|
if old_values.map_or(false, |v| v.get_font().clone_font_size() != new_font_size) &&
|
|
device.used_root_font_size() {
|
|
child_cascade_requirement = ChildCascadeRequirement::MustCascadeDescendants;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Set the new computed values.
|
|
cascade_visited.set_values(primary_style, new_values);
|
|
|
|
// Return whether the damage indicates we must cascade new inherited
|
|
// values into children.
|
|
child_cascade_requirement
|
|
}
|
|
|
|
/// Computes values and damage for the eager pseudo-element styles of an
|
|
/// element, setting them on the ElementData.
|
|
fn cascade_eager_pseudo(&self,
|
|
context: &mut StyleContext<Self>,
|
|
data: &mut ElementData,
|
|
pseudo: &PseudoElement,
|
|
cascade_visited: CascadeVisitedMode) {
|
|
debug_assert!(pseudo.is_eager());
|
|
let (mut styles, restyle) = data.styles_and_restyle_mut();
|
|
let mut pseudo_style = styles.pseudos.get_mut(pseudo).unwrap();
|
|
// If there was no relevant link, we won't have any visited rules, so
|
|
// there may not be anything do for the visited case. This early return
|
|
// is especially important for the `cascade_primary_and_pseudos` path
|
|
// since we rely on the state of some previous matching run.
|
|
if !cascade_visited.has_rules(pseudo_style) {
|
|
return
|
|
}
|
|
let old_values = cascade_visited.take_values(pseudo_style);
|
|
|
|
let new_values = self.cascade_internal(context,
|
|
&styles.primary,
|
|
Some(pseudo_style),
|
|
cascade_visited);
|
|
|
|
if cascade_visited.should_accumulate_damage() {
|
|
self.accumulate_damage(&context.shared,
|
|
restyle,
|
|
old_values.as_ref().map(|v| &**v),
|
|
&new_values,
|
|
Some(pseudo));
|
|
}
|
|
|
|
cascade_visited.set_values(pseudo_style, new_values);
|
|
}
|
|
|
|
/// get_after_change_style removes the transition rules from the ComputedValues.
|
|
/// If there is no transition rule in the ComputedValues, it returns None.
|
|
#[cfg(feature = "gecko")]
|
|
fn get_after_change_style(&self,
|
|
context: &mut StyleContext<Self>,
|
|
primary_style: &ComputedStyle)
|
|
-> Option<Arc<ComputedValues>> {
|
|
let rule_node = &primary_style.rules;
|
|
let without_transition_rules =
|
|
context.shared.stylist.rule_tree().remove_transition_rule_if_applicable(rule_node);
|
|
if without_transition_rules == *rule_node {
|
|
// We don't have transition rule in this case, so return None to let the caller
|
|
// use the original ComputedValues.
|
|
return None;
|
|
}
|
|
|
|
// This currently ignores visited styles, which seems acceptable,
|
|
// as existing browsers don't appear to transition visited styles.
|
|
Some(self.cascade_with_rules(context.shared,
|
|
&context.thread_local.font_metrics_provider,
|
|
&without_transition_rules,
|
|
primary_style,
|
|
InheritMode::Normal,
|
|
CascadeVisitedMode::Unvisited,
|
|
None))
|
|
}
|
|
|
|
#[cfg(feature = "gecko")]
|
|
fn needs_animations_update(&self,
|
|
context: &mut StyleContext<Self>,
|
|
old_values: Option<&Arc<ComputedValues>>,
|
|
new_values: &ComputedValues)
|
|
-> bool {
|
|
let new_box_style = new_values.get_box();
|
|
let has_new_animation_style = new_box_style.animation_name_count() >= 1 &&
|
|
new_box_style.animation_name_at(0).0.is_some();
|
|
let has_animations = self.has_css_animations();
|
|
|
|
old_values.map_or(has_new_animation_style, |old| {
|
|
let old_box_style = old.get_box();
|
|
let old_display_style = old_box_style.clone_display();
|
|
let new_display_style = new_box_style.clone_display();
|
|
|
|
// If the traverse is triggered by CSS rule changes,
|
|
// we need to try to update all CSS animations.
|
|
context.shared.traversal_flags.for_css_rule_changes() ||
|
|
!old_box_style.animations_equals(&new_box_style) ||
|
|
(old_display_style == display::T::none &&
|
|
new_display_style != display::T::none &&
|
|
has_new_animation_style) ||
|
|
(old_display_style != display::T::none &&
|
|
new_display_style == display::T::none &&
|
|
has_animations)
|
|
})
|
|
}
|
|
|
|
#[cfg(feature = "gecko")]
|
|
fn process_animations(&self,
|
|
context: &mut StyleContext<Self>,
|
|
old_values: &mut Option<Arc<ComputedValues>>,
|
|
new_values: &mut Arc<ComputedValues>,
|
|
primary_style: &ComputedStyle,
|
|
important_rules_changed: bool) {
|
|
use context::{CASCADE_RESULTS, CSS_ANIMATIONS, CSS_TRANSITIONS, EFFECT_PROPERTIES};
|
|
use context::UpdateAnimationsTasks;
|
|
|
|
let mut tasks = UpdateAnimationsTasks::empty();
|
|
if self.needs_animations_update(context, old_values.as_ref(), new_values) {
|
|
tasks.insert(CSS_ANIMATIONS);
|
|
}
|
|
|
|
let before_change_style = if self.might_need_transitions_update(old_values.as_ref().map(|s| &**s),
|
|
new_values) {
|
|
let after_change_style = if self.has_css_transitions() {
|
|
self.get_after_change_style(context, primary_style)
|
|
} else {
|
|
None
|
|
};
|
|
|
|
// In order to avoid creating a SequentialTask for transitions which
|
|
// may not be updated, we check it per property to make sure Gecko
|
|
// side will really update transition.
|
|
let needs_transitions_update = {
|
|
// We borrow new_values here, so need to add a scope to make
|
|
// sure we release it before assigning a new value to it.
|
|
let after_change_style_ref =
|
|
after_change_style.as_ref().unwrap_or(&new_values);
|
|
|
|
self.needs_transitions_update(old_values.as_ref().unwrap(),
|
|
after_change_style_ref)
|
|
};
|
|
|
|
if needs_transitions_update {
|
|
if let Some(values_without_transitions) = after_change_style {
|
|
*new_values = values_without_transitions;
|
|
}
|
|
tasks.insert(CSS_TRANSITIONS);
|
|
|
|
// We need to clone old_values into SequentialTask, so we can use it later.
|
|
old_values.clone()
|
|
} else {
|
|
None
|
|
}
|
|
} else {
|
|
None
|
|
};
|
|
|
|
if self.has_animations() {
|
|
tasks.insert(EFFECT_PROPERTIES);
|
|
if important_rules_changed {
|
|
tasks.insert(CASCADE_RESULTS);
|
|
}
|
|
}
|
|
|
|
if !tasks.is_empty() {
|
|
let task = ::context::SequentialTask::update_animations(*self,
|
|
before_change_style,
|
|
tasks);
|
|
context.thread_local.tasks.push(task);
|
|
}
|
|
}
|
|
|
|
#[cfg(feature = "servo")]
|
|
fn process_animations(&self,
|
|
context: &mut StyleContext<Self>,
|
|
old_values: &mut Option<Arc<ComputedValues>>,
|
|
new_values: &mut Arc<ComputedValues>,
|
|
_primary_style: &ComputedStyle,
|
|
_important_rules_changed: bool) {
|
|
use animation;
|
|
|
|
let possibly_expired_animations =
|
|
&mut context.thread_local.current_element_info.as_mut().unwrap()
|
|
.possibly_expired_animations;
|
|
let shared_context = context.shared;
|
|
if let Some(ref mut old) = *old_values {
|
|
self.update_animations_for_cascade(shared_context, old,
|
|
possibly_expired_animations,
|
|
&context.thread_local.font_metrics_provider);
|
|
}
|
|
|
|
let new_animations_sender = &context.thread_local.new_animations_sender;
|
|
let this_opaque = self.as_node().opaque();
|
|
// Trigger any present animations if necessary.
|
|
animation::maybe_start_animations(&shared_context,
|
|
new_animations_sender,
|
|
this_opaque, &new_values);
|
|
|
|
// Trigger transitions if necessary. This will reset `new_values` back
|
|
// to its old value if it did trigger a transition.
|
|
if let Some(ref values) = *old_values {
|
|
animation::start_transitions_if_applicable(
|
|
new_animations_sender,
|
|
this_opaque,
|
|
&**values,
|
|
new_values,
|
|
&shared_context.timer,
|
|
&possibly_expired_animations);
|
|
}
|
|
}
|
|
|
|
/// Computes and applies non-redundant damage.
|
|
#[cfg(feature = "gecko")]
|
|
fn accumulate_damage_for(&self,
|
|
shared_context: &SharedStyleContext,
|
|
restyle: &mut RestyleData,
|
|
old_values: &ComputedValues,
|
|
new_values: &Arc<ComputedValues>,
|
|
pseudo: Option<&PseudoElement>)
|
|
-> ChildCascadeRequirement {
|
|
// Don't accumulate damage if we're in a restyle for reconstruction.
|
|
if shared_context.traversal_flags.for_reconstruct() {
|
|
return ChildCascadeRequirement::MustCascadeChildren;
|
|
}
|
|
|
|
// If an ancestor is already getting reconstructed by Gecko's top-down
|
|
// frame constructor, no need to apply damage. Similarly if we already
|
|
// have an explicitly stored ReconstructFrame hint.
|
|
//
|
|
// See https://bugzilla.mozilla.org/show_bug.cgi?id=1301258#c12
|
|
// for followup work to make the optimization here more optimal by considering
|
|
// each bit individually.
|
|
let skip_applying_damage =
|
|
restyle.damage_handled.contains(RestyleDamage::reconstruct()) ||
|
|
restyle.damage.contains(RestyleDamage::reconstruct());
|
|
|
|
let difference = self.compute_style_difference(&old_values,
|
|
&new_values,
|
|
pseudo);
|
|
if !skip_applying_damage {
|
|
restyle.damage |= difference.damage;
|
|
}
|
|
difference.change.into()
|
|
}
|
|
|
|
/// Computes and applies restyle damage unless we've already maxed it out.
|
|
#[cfg(feature = "servo")]
|
|
fn accumulate_damage_for(&self,
|
|
_shared_context: &SharedStyleContext,
|
|
restyle: &mut RestyleData,
|
|
old_values: &ComputedValues,
|
|
new_values: &Arc<ComputedValues>,
|
|
pseudo: Option<&PseudoElement>)
|
|
-> ChildCascadeRequirement {
|
|
let difference = self.compute_style_difference(&old_values, &new_values, pseudo);
|
|
restyle.damage |= difference.damage;
|
|
difference.change.into()
|
|
}
|
|
|
|
#[cfg(feature = "servo")]
|
|
fn update_animations_for_cascade(&self,
|
|
context: &SharedStyleContext,
|
|
style: &mut Arc<ComputedValues>,
|
|
possibly_expired_animations: &mut Vec<::animation::PropertyAnimation>,
|
|
font_metrics: &FontMetricsProvider) {
|
|
use animation::{self, Animation};
|
|
|
|
// Finish any expired transitions.
|
|
let this_opaque = self.as_node().opaque();
|
|
animation::complete_expired_transitions(this_opaque, style, context);
|
|
|
|
// Merge any running transitions into the current style, and cancel them.
|
|
let had_running_animations = context.running_animations
|
|
.read()
|
|
.get(&this_opaque)
|
|
.is_some();
|
|
if had_running_animations {
|
|
let mut all_running_animations = context.running_animations.write();
|
|
for running_animation in all_running_animations.get_mut(&this_opaque).unwrap() {
|
|
// This shouldn't happen frequently, but under some
|
|
// circumstances mainly huge load or debug builds, the
|
|
// constellation might be delayed in sending the
|
|
// `TickAllAnimations` message to layout.
|
|
//
|
|
// Thus, we can't assume all the animations have been already
|
|
// updated by layout, because other restyle due to script might
|
|
// be triggered by layout before the animation tick.
|
|
//
|
|
// See #12171 and the associated PR for an example where this
|
|
// happened while debugging other release panic.
|
|
if !running_animation.is_expired() {
|
|
animation::update_style_for_animation(context,
|
|
running_animation,
|
|
style,
|
|
font_metrics);
|
|
if let Animation::Transition(_, _, ref frame, _) = *running_animation {
|
|
possibly_expired_animations.push(frame.property_animation.clone())
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<E: TElement> PrivateMatchMethods for E {}
|
|
|
|
/// Collects the outputs of the primary matching process, including the rule
|
|
/// node and other associated data.
|
|
#[derive(Debug)]
|
|
pub struct MatchingResults {
|
|
/// Whether the rules changed.
|
|
rules_changed: bool,
|
|
/// Whether there are any changes of important rules overriding animations.
|
|
important_rules_overriding_animation_changed: bool,
|
|
/// Records certains relations between elements noticed during matching (and
|
|
/// also extended after matching).
|
|
relations: StyleRelations,
|
|
/// Whether we encountered a "relevant link" while matching _any_ selector
|
|
/// for this element. (This differs from `RelevantLinkStatus` which tracks
|
|
/// the status for the _current_ selector only.)
|
|
relevant_link_found: bool,
|
|
}
|
|
|
|
impl MatchingResults {
|
|
/// Create `MatchingResults` with only the basic required outputs.
|
|
fn new(rules_changed: bool, important_rules: bool) -> Self {
|
|
Self {
|
|
rules_changed: rules_changed,
|
|
important_rules_overriding_animation_changed: important_rules,
|
|
relations: StyleRelations::default(),
|
|
relevant_link_found: false,
|
|
}
|
|
}
|
|
|
|
/// Create `MatchingResults` from the output fields of `MatchingContext`.
|
|
fn new_from_context(rules_changed: bool,
|
|
important_rules: bool,
|
|
context: MatchingContext)
|
|
-> Self {
|
|
Self {
|
|
rules_changed: rules_changed,
|
|
important_rules_overriding_animation_changed: important_rules,
|
|
relations: context.relations,
|
|
relevant_link_found: context.relevant_link_found,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The public API that elements expose for selector matching.
|
|
pub trait MatchMethods : TElement {
|
|
/// Performs selector matching and property cascading on an element and its
|
|
/// eager pseudos.
|
|
fn match_and_cascade(&self,
|
|
context: &mut StyleContext<Self>,
|
|
data: &mut ElementData,
|
|
sharing: StyleSharingBehavior)
|
|
-> ChildCascadeRequirement
|
|
{
|
|
debug!("Match and cascade for {:?}", self);
|
|
|
|
// Perform selector matching for the primary style.
|
|
let mut primary_results =
|
|
self.match_primary(context, data, VisitedHandlingMode::AllLinksUnvisited);
|
|
let important_rules_changed =
|
|
primary_results.important_rules_overriding_animation_changed;
|
|
|
|
// If there's a relevant link involved, match and cascade primary styles
|
|
// as if the link is visited as well. This is done before the regular
|
|
// cascade because the visited ComputedValues are placed within the
|
|
// regular ComputedValues, which is immutable after the cascade.
|
|
let relevant_link_found = primary_results.relevant_link_found;
|
|
if relevant_link_found {
|
|
self.match_primary(context, data, VisitedHandlingMode::RelevantLinkVisited);
|
|
self.cascade_primary(context, data, important_rules_changed,
|
|
CascadeVisitedMode::Visited);
|
|
}
|
|
|
|
// Cascade properties and compute primary values.
|
|
let child_cascade_requirement =
|
|
self.cascade_primary(context, data, important_rules_changed,
|
|
CascadeVisitedMode::Unvisited);
|
|
|
|
// Match and cascade eager pseudo-elements.
|
|
if !data.styles().is_display_none() {
|
|
self.match_pseudos(context, data, VisitedHandlingMode::AllLinksUnvisited);
|
|
|
|
// If there's a relevant link involved, match and cascade eager
|
|
// pseudo-element styles as if the link is visited as well.
|
|
// This runs after matching for regular styles because matching adds
|
|
// each pseudo as needed to the PseudoMap, and this runs before
|
|
// cascade for regular styles because the visited ComputedValues
|
|
// are placed within the regular ComputedValues, which is immutable
|
|
// after the cascade.
|
|
if relevant_link_found {
|
|
self.match_pseudos(context, data, VisitedHandlingMode::RelevantLinkVisited);
|
|
self.cascade_pseudos(context, data, CascadeVisitedMode::Visited);
|
|
}
|
|
|
|
self.cascade_pseudos(context, data, CascadeVisitedMode::Unvisited);
|
|
}
|
|
|
|
// If we have any pseudo elements, indicate so in the primary StyleRelations.
|
|
if !data.styles().pseudos.is_empty() {
|
|
primary_results.relations |= AFFECTED_BY_PSEUDO_ELEMENTS;
|
|
}
|
|
|
|
// If the style is shareable, add it to the LRU cache.
|
|
if sharing == StyleSharingBehavior::Allow {
|
|
// If we previously tried to match this element against the cache,
|
|
// the revalidation match results will already be cached. Otherwise
|
|
// we'll have None, and compute them later on-demand.
|
|
//
|
|
// If we do have the results, grab them here to satisfy the borrow
|
|
// checker.
|
|
let validation_data =
|
|
context.thread_local
|
|
.current_element_info
|
|
.as_mut().unwrap()
|
|
.validation_data
|
|
.take();
|
|
|
|
let dom_depth = context.thread_local.bloom_filter.matching_depth();
|
|
context.thread_local
|
|
.style_sharing_candidate_cache
|
|
.insert_if_possible(self,
|
|
data.styles().primary.values(),
|
|
primary_results.relations,
|
|
validation_data,
|
|
dom_depth);
|
|
}
|
|
|
|
child_cascade_requirement
|
|
}
|
|
|
|
/// Performs the cascade, without matching.
|
|
fn cascade_primary_and_pseudos(&self,
|
|
context: &mut StyleContext<Self>,
|
|
mut data: &mut ElementData,
|
|
important_rules_changed: bool)
|
|
-> ChildCascadeRequirement
|
|
{
|
|
// If there's a relevant link involved, cascade styles as if the link is
|
|
// visited as well. This is done before the regular cascade because the
|
|
// visited ComputedValues are placed within the regular ComputedValues,
|
|
// which is immutable after the cascade. If there aren't any visited
|
|
// rules, these calls will return without cascading.
|
|
self.cascade_primary(context, &mut data, important_rules_changed,
|
|
CascadeVisitedMode::Visited);
|
|
let child_cascade_requirement =
|
|
self.cascade_primary(context, &mut data, important_rules_changed,
|
|
CascadeVisitedMode::Unvisited);
|
|
self.cascade_pseudos(context, &mut data, CascadeVisitedMode::Visited);
|
|
self.cascade_pseudos(context, &mut data, CascadeVisitedMode::Unvisited);
|
|
child_cascade_requirement
|
|
}
|
|
|
|
/// Runs selector matching to (re)compute the primary rule node for this
|
|
/// element.
|
|
///
|
|
/// Returns `MatchingResults` with the new rules and other associated data
|
|
/// from the matching process.
|
|
fn match_primary(&self,
|
|
context: &mut StyleContext<Self>,
|
|
data: &mut ElementData,
|
|
visited_handling: VisitedHandlingMode)
|
|
-> MatchingResults
|
|
{
|
|
debug!("Match primary for {:?}, visited: {:?}", self, visited_handling);
|
|
|
|
let only_default_rules = context.shared.traversal_flags.for_default_styles();
|
|
let implemented_pseudo = self.implemented_pseudo_element();
|
|
if let Some(ref pseudo) = implemented_pseudo {
|
|
// We don't expect to match against a non-canonical pseudo-element.
|
|
debug_assert_eq!(*pseudo, pseudo.canonical());
|
|
if pseudo.is_eager() && !only_default_rules {
|
|
// If it's an eager element-backed pseudo, we can generally just
|
|
// grab the matched rules from the parent, and then update
|
|
// animations.
|
|
//
|
|
// However, if we're computing default styles, then we might
|
|
// have traversed to this pseudo-implementing element without
|
|
// any pseudo styles stored on the parent. For example, if
|
|
// document-level style sheets cause the element to exist, due
|
|
// to ::before rules, then those rules won't be found when
|
|
// computing default styles on the parent, so we won't have
|
|
// bothered to store pseudo styles there. In this case, we just
|
|
// treat it like a lazily computed pseudo.
|
|
let parent = self.parent_element().unwrap();
|
|
let parent_data = parent.borrow_data().unwrap();
|
|
let pseudo_style =
|
|
parent_data.styles().pseudos.get(&pseudo).unwrap();
|
|
let mut rules = pseudo_style.rules.clone();
|
|
if parent.may_have_animations() {
|
|
let animation_rules = data.get_animation_rules();
|
|
|
|
// Handle animations here.
|
|
if let Some(animation_rule) = animation_rules.0 {
|
|
let animation_rule_node =
|
|
context.shared.stylist.rule_tree()
|
|
.update_rule_at_level(CascadeLevel::Animations,
|
|
Some(&animation_rule),
|
|
&mut rules,
|
|
&context.shared.guards);
|
|
if let Some(node) = animation_rule_node {
|
|
rules = node;
|
|
}
|
|
}
|
|
|
|
if let Some(animation_rule) = animation_rules.1 {
|
|
let animation_rule_node =
|
|
context.shared.stylist.rule_tree()
|
|
.update_rule_at_level(CascadeLevel::Transitions,
|
|
Some(&animation_rule),
|
|
&mut rules,
|
|
&context.shared.guards);
|
|
if let Some(node) = animation_rule_node {
|
|
rules = node;
|
|
}
|
|
}
|
|
}
|
|
let important_rules_changed =
|
|
self.has_animations() &&
|
|
data.has_styles() &&
|
|
data.important_rules_are_different(&rules,
|
|
&context.shared.guards);
|
|
|
|
let rules_changed = match visited_handling {
|
|
VisitedHandlingMode::AllLinksUnvisited => {
|
|
data.set_primary_rules(rules)
|
|
},
|
|
VisitedHandlingMode::RelevantLinkVisited => {
|
|
data.styles_mut().primary.set_visited_rules(rules)
|
|
},
|
|
};
|
|
|
|
return MatchingResults::new(rules_changed, important_rules_changed)
|
|
}
|
|
}
|
|
|
|
let mut applicable_declarations = ApplicableDeclarationList::new();
|
|
|
|
let stylist = &context.shared.stylist;
|
|
let style_attribute = self.style_attribute();
|
|
|
|
let map = &mut context.thread_local.selector_flags;
|
|
let mut set_selector_flags = |element: &Self, flags: ElementSelectorFlags| {
|
|
self.apply_selector_flags(map, element, flags);
|
|
};
|
|
|
|
let rule_inclusion = if only_default_rules {
|
|
RuleInclusion::DefaultOnly
|
|
} else {
|
|
RuleInclusion::All
|
|
};
|
|
|
|
let bloom_filter = context.thread_local.bloom_filter.filter();
|
|
let mut matching_context =
|
|
MatchingContext::new_for_visited(MatchingMode::Normal,
|
|
Some(bloom_filter),
|
|
visited_handling);
|
|
|
|
{
|
|
let smil_override = data.get_smil_override();
|
|
let animation_rules = if self.may_have_animations() {
|
|
data.get_animation_rules()
|
|
} else {
|
|
AnimationRules(None, None)
|
|
};
|
|
|
|
// Compute the primary rule node.
|
|
stylist.push_applicable_declarations(self,
|
|
implemented_pseudo.as_ref(),
|
|
style_attribute,
|
|
smil_override,
|
|
animation_rules,
|
|
rule_inclusion,
|
|
&mut applicable_declarations,
|
|
&mut matching_context,
|
|
&mut set_selector_flags);
|
|
}
|
|
self.unset_dirty_style_attribute();
|
|
|
|
let primary_rule_node = stylist.rule_tree().compute_rule_node(
|
|
&mut applicable_declarations,
|
|
&context.shared.guards
|
|
);
|
|
|
|
if log_enabled!(Trace) {
|
|
trace!("Matched rules:");
|
|
for rn in primary_rule_node.self_and_ancestors() {
|
|
if let Some(source) = rn.style_source() {
|
|
trace!(" > {:?}", source);
|
|
}
|
|
}
|
|
}
|
|
|
|
let important_rules_changed =
|
|
self.has_animations() &&
|
|
data.has_styles() &&
|
|
data.important_rules_are_different(
|
|
&primary_rule_node,
|
|
&context.shared.guards
|
|
);
|
|
|
|
let rules_changed = match visited_handling {
|
|
VisitedHandlingMode::AllLinksUnvisited => {
|
|
data.set_primary_rules(primary_rule_node)
|
|
},
|
|
VisitedHandlingMode::RelevantLinkVisited => {
|
|
data.styles_mut().primary.set_visited_rules(primary_rule_node)
|
|
},
|
|
};
|
|
|
|
MatchingResults::new_from_context(rules_changed,
|
|
important_rules_changed,
|
|
matching_context)
|
|
}
|
|
|
|
/// Runs selector matching to (re)compute eager pseudo-element rule nodes
|
|
/// for this element.
|
|
fn match_pseudos(&self,
|
|
context: &mut StyleContext<Self>,
|
|
data: &mut ElementData,
|
|
visited_handling: VisitedHandlingMode)
|
|
{
|
|
debug!("Match pseudos for {:?}, visited: {:?}", self, visited_handling);
|
|
|
|
if self.implemented_pseudo_element().is_some() {
|
|
// Element pseudos can't have any other pseudo.
|
|
return;
|
|
}
|
|
|
|
let mut applicable_declarations = ApplicableDeclarationList::new();
|
|
|
|
let map = &mut context.thread_local.selector_flags;
|
|
let mut set_selector_flags = |element: &Self, flags: ElementSelectorFlags| {
|
|
self.apply_selector_flags(map, element, flags);
|
|
};
|
|
|
|
// Borrow the stuff we need here so the borrow checker doesn't get mad
|
|
// at us later in the closure.
|
|
let stylist = &context.shared.stylist;
|
|
let guards = &context.shared.guards;
|
|
|
|
let rule_inclusion = if context.shared.traversal_flags.for_default_styles() {
|
|
RuleInclusion::DefaultOnly
|
|
} else {
|
|
RuleInclusion::All
|
|
};
|
|
|
|
let bloom_filter = context.thread_local.bloom_filter.filter();
|
|
|
|
let mut matching_context =
|
|
MatchingContext::new_for_visited(MatchingMode::ForStatelessPseudoElement,
|
|
Some(bloom_filter),
|
|
visited_handling);
|
|
|
|
// Compute rule nodes for eagerly-cascaded pseudo-elements.
|
|
let mut matches_different_pseudos = false;
|
|
SelectorImpl::each_eagerly_cascaded_pseudo_element(|pseudo| {
|
|
// For pseudo-elements, we only try to match visited rules if there
|
|
// are also unvisited rules. (This matches Gecko's behavior.)
|
|
if visited_handling == VisitedHandlingMode::RelevantLinkVisited &&
|
|
!data.styles().pseudos.has(&pseudo) {
|
|
return
|
|
}
|
|
|
|
if !self.may_generate_pseudo(&pseudo, data.styles().primary.values()) {
|
|
return;
|
|
}
|
|
|
|
debug_assert!(applicable_declarations.is_empty());
|
|
// NB: We handle animation rules for ::before and ::after when
|
|
// traversing them.
|
|
stylist.push_applicable_declarations(self,
|
|
Some(&pseudo),
|
|
None,
|
|
None,
|
|
AnimationRules(None, None),
|
|
rule_inclusion,
|
|
&mut applicable_declarations,
|
|
&mut matching_context,
|
|
&mut set_selector_flags);
|
|
|
|
let pseudos = &mut data.styles_mut().pseudos;
|
|
if !applicable_declarations.is_empty() {
|
|
let rules = stylist.rule_tree().compute_rule_node(
|
|
&mut applicable_declarations,
|
|
&guards
|
|
);
|
|
matches_different_pseudos |= pseudos.add_rules(
|
|
&pseudo,
|
|
visited_handling,
|
|
rules
|
|
);
|
|
} else {
|
|
matches_different_pseudos |= pseudos.remove_rules(
|
|
&pseudo,
|
|
visited_handling
|
|
);
|
|
}
|
|
});
|
|
|
|
if matches_different_pseudos {
|
|
if let Some(r) = data.get_restyle_mut() {
|
|
// Any changes to the matched pseudo-elements trigger
|
|
// reconstruction.
|
|
r.damage |= RestyleDamage::reconstruct();
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Applies selector flags to an element, deferring mutations of the parent
|
|
/// until after the traversal.
|
|
///
|
|
/// TODO(emilio): This is somewhat inefficient, because of a variety of
|
|
/// reasons:
|
|
///
|
|
/// * It doesn't coalesce flags.
|
|
/// * It doesn't look at flags already sent in a task for the main
|
|
/// thread to process.
|
|
/// * It doesn't take advantage of us knowing that the traversal is
|
|
/// sequential.
|
|
///
|
|
/// I suspect (need to measure!) that we don't use to set flags on
|
|
/// a lot of different elements, but we could end up posting the same
|
|
/// flag over and over with this approach.
|
|
///
|
|
/// If the number of elements is low, perhaps a small cache with the
|
|
/// flags already sent would be appropriate.
|
|
///
|
|
/// The sequential task business for this is kind of sad :(.
|
|
///
|
|
/// Anyway, let's do the obvious thing for now.
|
|
fn apply_selector_flags(&self,
|
|
map: &mut SelectorFlagsMap<Self>,
|
|
element: &Self,
|
|
flags: ElementSelectorFlags) {
|
|
// Handle flags that apply to the element.
|
|
let self_flags = flags.for_self();
|
|
if !self_flags.is_empty() {
|
|
if element == self {
|
|
// If this is the element we're styling, we have exclusive
|
|
// access to the element, and thus it's fine inserting them,
|
|
// even from the worker.
|
|
unsafe { element.set_selector_flags(self_flags); }
|
|
} else {
|
|
// Otherwise, this element is an ancestor of the current element
|
|
// we're styling, and thus multiple children could write to it
|
|
// if we did from here.
|
|
//
|
|
// Instead, we can read them, and post them if necessary as a
|
|
// sequential task in order for them to be processed later.
|
|
if !element.has_selector_flags(self_flags) {
|
|
map.insert_flags(*element, self_flags);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Handle flags that apply to the parent.
|
|
let parent_flags = flags.for_parent();
|
|
if !parent_flags.is_empty() {
|
|
if let Some(p) = element.parent_element() {
|
|
if !p.has_selector_flags(parent_flags) {
|
|
map.insert_flags(p, parent_flags);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Computes and applies restyle damage.
|
|
fn accumulate_damage(&self,
|
|
shared_context: &SharedStyleContext,
|
|
restyle: Option<&mut RestyleData>,
|
|
old_values: Option<&ComputedValues>,
|
|
new_values: &Arc<ComputedValues>,
|
|
pseudo: Option<&PseudoElement>)
|
|
-> ChildCascadeRequirement {
|
|
let restyle = match restyle {
|
|
Some(r) => r,
|
|
None => return ChildCascadeRequirement::MustCascadeChildren,
|
|
};
|
|
|
|
let old_values = match old_values {
|
|
Some(v) => v,
|
|
None => return ChildCascadeRequirement::MustCascadeChildren,
|
|
};
|
|
|
|
// ::before and ::after are element-backed in Gecko, so they do the
|
|
// damage calculation for themselves, when there's an actual pseudo.
|
|
let is_existing_before_or_after =
|
|
cfg!(feature = "gecko") &&
|
|
pseudo.map_or(false, |p| p.is_before_or_after()) &&
|
|
self.existing_style_for_restyle_damage(old_values, pseudo)
|
|
.is_some();
|
|
|
|
if is_existing_before_or_after {
|
|
return ChildCascadeRequirement::CanSkipCascade;
|
|
}
|
|
|
|
self.accumulate_damage_for(shared_context,
|
|
restyle,
|
|
old_values,
|
|
new_values,
|
|
pseudo)
|
|
}
|
|
|
|
/// Updates the rule nodes without re-running selector matching, using just
|
|
/// the rule tree.
|
|
///
|
|
/// Returns true if an !important rule was replaced.
|
|
fn replace_rules(&self,
|
|
replacements: RestyleReplacements,
|
|
context: &StyleContext<Self>,
|
|
data: &mut ElementData)
|
|
-> bool {
|
|
let mut result = false;
|
|
result |= self.replace_rules_internal(replacements, context, data,
|
|
CascadeVisitedMode::Unvisited);
|
|
if !context.shared.traversal_flags.for_animation_only() {
|
|
result |= self.replace_rules_internal(replacements, context, data,
|
|
CascadeVisitedMode::Visited);
|
|
}
|
|
result
|
|
}
|
|
|
|
/// Updates the rule nodes without re-running selector matching, using just
|
|
/// the rule tree, for a specific visited mode.
|
|
///
|
|
/// Returns true if an !important rule was replaced.
|
|
fn replace_rules_internal(&self,
|
|
replacements: RestyleReplacements,
|
|
context: &StyleContext<Self>,
|
|
data: &mut ElementData,
|
|
cascade_visited: CascadeVisitedMode)
|
|
-> bool {
|
|
use properties::PropertyDeclarationBlock;
|
|
use shared_lock::Locked;
|
|
|
|
let element_styles = &mut data.styles_mut();
|
|
let primary_rules = match cascade_visited.get_rules_mut(&mut element_styles.primary) {
|
|
Some(r) => r,
|
|
None => return false,
|
|
};
|
|
|
|
let replace_rule_node = |level: CascadeLevel,
|
|
pdb: Option<&Arc<Locked<PropertyDeclarationBlock>>>,
|
|
path: &mut StrongRuleNode| -> bool {
|
|
let new_node = context.shared.stylist.rule_tree()
|
|
.update_rule_at_level(level, pdb, path, &context.shared.guards);
|
|
match new_node {
|
|
Some(n) => {
|
|
*path = n;
|
|
level.is_important()
|
|
},
|
|
None => false,
|
|
}
|
|
};
|
|
|
|
if !context.shared.traversal_flags.for_animation_only() {
|
|
let mut result = false;
|
|
if replacements.contains(RESTYLE_STYLE_ATTRIBUTE) {
|
|
let style_attribute = self.style_attribute();
|
|
result |= replace_rule_node(CascadeLevel::StyleAttributeNormal,
|
|
style_attribute,
|
|
primary_rules);
|
|
result |= replace_rule_node(CascadeLevel::StyleAttributeImportant,
|
|
style_attribute,
|
|
primary_rules);
|
|
self.unset_dirty_style_attribute();
|
|
}
|
|
return result;
|
|
}
|
|
|
|
// Animation restyle hints are processed prior to other restyle
|
|
// hints in the animation-only traversal.
|
|
//
|
|
// Non-animation restyle hints will be processed in a subsequent
|
|
// normal traversal.
|
|
if replacements.intersects(RestyleReplacements::for_animations()) {
|
|
debug_assert!(context.shared.traversal_flags.for_animation_only());
|
|
|
|
if replacements.contains(RESTYLE_SMIL) {
|
|
replace_rule_node(CascadeLevel::SMILOverride,
|
|
self.get_smil_override(),
|
|
primary_rules);
|
|
}
|
|
|
|
let replace_rule_node_for_animation = |level: CascadeLevel,
|
|
primary_rules: &mut StrongRuleNode| {
|
|
let animation_rule = self.get_animation_rule_by_cascade(level);
|
|
replace_rule_node(level,
|
|
animation_rule.as_ref(),
|
|
primary_rules);
|
|
};
|
|
|
|
// Apply Transition rules and Animation rules if the corresponding restyle hint
|
|
// is contained.
|
|
if replacements.contains(RESTYLE_CSS_TRANSITIONS) {
|
|
replace_rule_node_for_animation(CascadeLevel::Transitions,
|
|
primary_rules);
|
|
}
|
|
|
|
if replacements.contains(RESTYLE_CSS_ANIMATIONS) {
|
|
replace_rule_node_for_animation(CascadeLevel::Animations,
|
|
primary_rules);
|
|
}
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
/// Given the old and new style of this element, and whether it's a
|
|
/// pseudo-element, compute the restyle damage used to determine which
|
|
/// kind of layout or painting operations we'll need.
|
|
fn compute_style_difference(&self,
|
|
old_values: &ComputedValues,
|
|
new_values: &Arc<ComputedValues>,
|
|
pseudo: Option<&PseudoElement>)
|
|
-> StyleDifference
|
|
{
|
|
if let Some(source) = self.existing_style_for_restyle_damage(old_values, pseudo) {
|
|
return RestyleDamage::compute_style_difference(source, new_values)
|
|
}
|
|
|
|
let new_style_is_display_none =
|
|
new_values.get_box().clone_display() == display::T::none;
|
|
let old_style_is_display_none =
|
|
old_values.get_box().clone_display() == display::T::none;
|
|
|
|
// If there's no style source, that likely means that Gecko couldn't
|
|
// find a style context.
|
|
//
|
|
// This happens with display:none elements, and not-yet-existing
|
|
// pseudo-elements.
|
|
if new_style_is_display_none && old_style_is_display_none {
|
|
// The style remains display:none. No need for damage.
|
|
return StyleDifference::new(RestyleDamage::empty(), StyleChange::Unchanged)
|
|
}
|
|
|
|
if pseudo.map_or(false, |p| p.is_before_or_after()) {
|
|
if (old_style_is_display_none ||
|
|
old_values.ineffective_content_property()) &&
|
|
(new_style_is_display_none ||
|
|
new_values.ineffective_content_property()) {
|
|
// The pseudo-element will remain undisplayed, so just avoid
|
|
// triggering any change.
|
|
return StyleDifference::new(RestyleDamage::empty(), StyleChange::Unchanged)
|
|
}
|
|
return StyleDifference::new(RestyleDamage::reconstruct(), StyleChange::Changed)
|
|
}
|
|
|
|
// Something else. Be conservative for now.
|
|
warn!("Reframing due to lack of old style source: {:?}, pseudo: {:?}",
|
|
self, pseudo);
|
|
// Something else. Be conservative for now.
|
|
StyleDifference::new(RestyleDamage::reconstruct(), StyleChange::Changed)
|
|
}
|
|
|
|
/// Performs the cascade for the element's eager pseudos.
|
|
fn cascade_pseudos(&self,
|
|
context: &mut StyleContext<Self>,
|
|
mut data: &mut ElementData,
|
|
cascade_visited: CascadeVisitedMode)
|
|
{
|
|
debug!("Cascade pseudos for {:?}, visited: {:?}", self,
|
|
cascade_visited);
|
|
// Note that we've already set up the map of matching pseudo-elements
|
|
// in match_pseudos (and handled the damage implications of changing
|
|
// which pseudos match), so now we can just iterate what we have. This
|
|
// does mean collecting owned pseudos, so that the borrow checker will
|
|
// let us pass the mutable |data| to the cascade function.
|
|
let matched_pseudos = data.styles().pseudos.keys();
|
|
for pseudo in matched_pseudos {
|
|
self.cascade_eager_pseudo(context, data, &pseudo, cascade_visited);
|
|
}
|
|
}
|
|
|
|
/// Returns computed values without animation and transition rules.
|
|
fn get_base_style(&self,
|
|
shared_context: &SharedStyleContext,
|
|
font_metrics_provider: &FontMetricsProvider,
|
|
primary_style: &ComputedStyle,
|
|
pseudo_style: Option<&ComputedStyle>)
|
|
-> Arc<ComputedValues> {
|
|
let relevant_style = pseudo_style.unwrap_or(primary_style);
|
|
let rule_node = &relevant_style.rules;
|
|
let without_animation_rules =
|
|
shared_context.stylist.rule_tree().remove_animation_rules(rule_node);
|
|
if without_animation_rules == *rule_node {
|
|
// Note that unwrapping here is fine, because the style is
|
|
// only incomplete during the styling process.
|
|
return relevant_style.values.as_ref().unwrap().clone();
|
|
}
|
|
|
|
// This currently ignores visited styles, which seems acceptable,
|
|
// as existing browsers don't appear to animate visited styles.
|
|
self.cascade_with_rules(shared_context,
|
|
font_metrics_provider,
|
|
&without_animation_rules,
|
|
primary_style,
|
|
InheritMode::Normal,
|
|
CascadeVisitedMode::Unvisited,
|
|
None)
|
|
}
|
|
|
|
}
|
|
|
|
impl<E: TElement> MatchMethods for E {}
|