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/* 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
//! Gecko's definition of a pseudo-element.
//!
//! Note that a few autogenerated bits of this live in
//! `pseudo_element_definition.mako.rs`. If you touch that file, you probably
//! need to update the checked-in files for Servo.
use crate::gecko_bindings::structs::{self, PseudoStyleType};
use crate::properties::longhands::display::computed_value::T as Display;
use crate::properties::{ComputedValues, PropertyFlags};
use crate::selector_parser::{PseudoElementCascadeType, SelectorImpl};
use crate::str::{starts_with_ignore_ascii_case, string_as_ascii_lowercase};
use crate::string_cache::Atom;
use crate::values::serialize_atom_identifier;
use crate::values::AtomIdent;
use cssparser::ToCss;
use static_prefs::pref;
use std::fmt;
include!(concat!(
env!("OUT_DIR"),
"/gecko/pseudo_element_definition.rs"
));
impl ::selectors::parser::PseudoElement for PseudoElement {
type Impl = SelectorImpl;
// ::slotted() should support all tree-abiding pseudo-elements, see
#[inline]
fn valid_after_slotted(&self) -> bool {
matches!(
*self,
Self::Before |
Self::After |
Self::Marker |
Self::Placeholder |
Self::FileSelectorButton
)
}
#[inline]
fn accepts_state_pseudo_classes(&self) -> bool {
// Note: if the pseudo element is a descendants of a pseudo element, `only-child` should be
// allowed after it.
self.supports_user_action_state() || self.is_in_pseudo_element_tree()
}
#[inline]
fn specificity_count(&self) -> u32 {
self.specificity_count()
}
#[inline]
fn is_in_pseudo_element_tree(&self) -> bool {
// All the named view transition pseudo-elements are the descendants of a pseudo-element
// root.
self.is_named_view_transition()
}
}
impl PseudoElement {
/// Returns the kind of cascade type that a given pseudo is going to use.
///
/// In Gecko we only compute ::before and ::after eagerly. We save the rules
/// for anonymous boxes separately, so we resolve them as precomputed
/// pseudos.
///
/// We resolve the others lazily, see `Servo_ResolvePseudoStyle`.
pub fn cascade_type(&self) -> PseudoElementCascadeType {
if self.is_eager() {
debug_assert!(!self.is_anon_box());
return PseudoElementCascadeType::Eager;
}
if self.is_precomputed() {
return PseudoElementCascadeType::Precomputed;
}
PseudoElementCascadeType::Lazy
}
/// Gets the canonical index of this eagerly-cascaded pseudo-element.
#[inline]
pub fn eager_index(&self) -> usize {
EAGER_PSEUDOS
.iter()
.position(|p| p == self)
.expect("Not an eager pseudo")
}
/// Creates a pseudo-element from an eager index.
#[inline]
pub fn from_eager_index(i: usize) -> Self {
EAGER_PSEUDOS[i].clone()
}
/// Whether animations for the current pseudo element are stored in the
/// parent element.
#[inline]
pub fn animations_stored_in_parent(&self) -> bool {
matches!(*self, Self::Before | Self::After | Self::Marker)
}
/// Whether the current pseudo element is ::before or ::after.
#[inline]
pub fn is_before_or_after(&self) -> bool {
matches!(*self, Self::Before | Self::After)
}
/// Whether this pseudo-element is the ::before pseudo.
#[inline]
pub fn is_before(&self) -> bool {
*self == PseudoElement::Before
}
/// Whether this pseudo-element is the ::after pseudo.
#[inline]
pub fn is_after(&self) -> bool {
*self == PseudoElement::After
}
/// Whether this pseudo-element is the ::marker pseudo.
#[inline]
pub fn is_marker(&self) -> bool {
*self == PseudoElement::Marker
}
/// Whether this pseudo-element is the ::selection pseudo.
#[inline]
pub fn is_selection(&self) -> bool {
*self == PseudoElement::Selection
}
/// Whether this pseudo-element is ::first-letter.
#[inline]
pub fn is_first_letter(&self) -> bool {
*self == PseudoElement::FirstLetter
}
/// Whether this pseudo-element is ::first-line.
#[inline]
pub fn is_first_line(&self) -> bool {
*self == PseudoElement::FirstLine
}
/// Whether this pseudo-element is the ::-moz-color-swatch pseudo.
#[inline]
pub fn is_color_swatch(&self) -> bool {
*self == PseudoElement::MozColorSwatch
}
/// Whether this pseudo-element is lazily-cascaded.
#[inline]
pub fn is_lazy(&self) -> bool {
!self.is_eager() && !self.is_precomputed()
}
/// The identifier of the highlight this pseudo-element represents.
pub fn highlight_name(&self) -> Option<&AtomIdent> {
match *self {
Self::Highlight(ref name) => Some(name),
_ => None,
}
}
/// Whether this pseudo-element is the ::highlight pseudo.
pub fn is_highlight(&self) -> bool {
matches!(*self, Self::Highlight(_))
}
/// Whether this pseudo-element is the ::target-text pseudo.
#[inline]
pub fn is_target_text(&self) -> bool {
*self == PseudoElement::TargetText
}
/// Whether this pseudo-element is a named view transition pseudo-element.
pub fn is_named_view_transition(&self) -> bool {
matches!(
*self,
Self::ViewTransitionGroup(..) |
Self::ViewTransitionImagePair(..) |
Self::ViewTransitionOld(..) |
Self::ViewTransitionNew(..)
)
}
/// The count we contribute to the specificity from this pseudo-element.
pub fn specificity_count(&self) -> u32 {
match *self {
Self::ViewTransitionGroup(ref name) |
Self::ViewTransitionImagePair(ref name) |
Self::ViewTransitionOld(ref name) |
Self::ViewTransitionNew(ref name) => {
// The specificity of a named view transition pseudo-element selector with a
// `<custom-ident>` argument is equivalent to a type selector.
// The specificity of a named view transition pseudo-element selector with a `*`
// argument is zero.
(name.0 != atom!("*")) as u32
},
_ => 1,
}
}
/// Whether this pseudo-element supports user action selectors.
pub fn supports_user_action_state(&self) -> bool {
(self.flags() & structs::CSS_PSEUDO_ELEMENT_SUPPORTS_USER_ACTION_STATE) != 0
}
/// Whether this pseudo-element is enabled for all content.
pub fn enabled_in_content(&self) -> bool {
match *self {
Self::Highlight(..) => pref!("dom.customHighlightAPI.enabled"),
Self::TargetText => pref!("dom.text_fragments.enabled"),
Self::SliderFill | Self::SliderTrack | Self::SliderThumb => {
pref!("layout.css.modern-range-pseudos.enabled")
},
Self::ViewTransition |
Self::ViewTransitionGroup(..) |
Self::ViewTransitionImagePair(..) |
Self::ViewTransitionOld(..) |
Self::ViewTransitionNew(..) => pref!("dom.viewTransitions.enabled"),
// If it's not explicitly enabled in UA sheets or chrome, then we're enabled for
// content.
_ => (self.flags() & structs::CSS_PSEUDO_ELEMENT_ENABLED_IN_UA_SHEETS_AND_CHROME) == 0,
}
}
/// Whether this pseudo is enabled explicitly in UA sheets.
pub fn enabled_in_ua_sheets(&self) -> bool {
(self.flags() & structs::CSS_PSEUDO_ELEMENT_ENABLED_IN_UA_SHEETS) != 0
}
/// Whether this pseudo is enabled explicitly in chrome sheets.
pub fn enabled_in_chrome(&self) -> bool {
(self.flags() & structs::CSS_PSEUDO_ELEMENT_ENABLED_IN_CHROME) != 0
}
/// Whether this pseudo-element skips flex/grid container display-based
/// fixup.
#[inline]
pub fn skip_item_display_fixup(&self) -> bool {
(self.flags() & structs::CSS_PSEUDO_ELEMENT_IS_FLEX_OR_GRID_ITEM) == 0
}
/// Whether this pseudo-element is precomputed.
#[inline]
pub fn is_precomputed(&self) -> bool {
self.is_anon_box() && !self.is_tree_pseudo_element()
}
/// Property flag that properties must have to apply to this pseudo-element.
#[inline]
pub fn property_restriction(&self) -> Option<PropertyFlags> {
Some(match *self {
PseudoElement::FirstLetter => PropertyFlags::APPLIES_TO_FIRST_LETTER,
PseudoElement::FirstLine => PropertyFlags::APPLIES_TO_FIRST_LINE,
PseudoElement::Placeholder => PropertyFlags::APPLIES_TO_PLACEHOLDER,
PseudoElement::Cue => PropertyFlags::APPLIES_TO_CUE,
PseudoElement::Marker if static_prefs::pref!("layout.css.marker.restricted") => {
PropertyFlags::APPLIES_TO_MARKER
},
_ => return None,
})
}
/// Whether this pseudo-element should actually exist if it has
/// the given styles.
pub fn should_exist(&self, style: &ComputedValues) -> bool {
debug_assert!(self.is_eager());
if style.get_box().clone_display() == Display::None {
return false;
}
if self.is_before_or_after() && style.ineffective_content_property() {
return false;
}
true
}
}