Move MatchingContext to a new module

This commit is contained in:
Simon Sapin 2017-06-13 00:31:29 +02:00
parent c5c1c1b350
commit 700aaf2bd6
3 changed files with 141 additions and 132 deletions

View file

@ -2,33 +2,20 @@
* 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/. */
use attr::{ParsedAttrSelectorOperation, AttrSelectorOperation, NamespaceConstraint, CaseSensitivity};
use attr::{ParsedAttrSelectorOperation, AttrSelectorOperation, NamespaceConstraint};
use bloom::{BLOOM_HASH_MASK, BloomFilter};
use parser::{AncestorHashes, Combinator, Component, LocalName};
use parser::{Selector, SelectorImpl, SelectorIter, SelectorList};
use std::borrow::Borrow;
use tree::Element;
pub use context::*;
// The bloom filter for descendant CSS selectors will have a <1% false
// positive rate until it has this many selectors in it, then it will
// rapidly increase.
pub static RECOMMENDED_SELECTOR_BLOOM_FILTER_SIZE: usize = 4096;
bitflags! {
/// Set of flags that determine the different kind of elements affected by
/// the selector matching process.
///
/// This is used to implement efficient sharing.
#[derive(Default)]
pub flags StyleRelations: usize {
/// Whether this element is affected by presentational hints. This is
/// computed externally (that is, in Servo).
const AFFECTED_BY_PRESENTATIONAL_HINTS = 1 << 0,
/// Whether this element has pseudo-element styles. Computed externally.
const AFFECTED_BY_PSEUDO_ELEMENTS = 1 << 1,
}
}
bitflags! {
/// Set of flags that are set on either the element or its parent (depending
/// on the flag) if the element could potentially match a selector.
@ -66,122 +53,6 @@ impl ElementSelectorFlags {
}
}
/// What kind of selector matching mode we should use.
///
/// There are two modes of selector matching. The difference is only noticeable
/// in presence of pseudo-elements.
#[derive(Debug, PartialEq, Copy, Clone)]
pub enum MatchingMode {
/// Don't ignore any pseudo-element selectors.
Normal,
/// Ignores any stateless pseudo-element selectors in the rightmost sequence
/// of simple selectors.
///
/// This is useful, for example, to match against ::before when you aren't a
/// pseudo-element yourself.
///
/// For example, in presence of `::before:hover`, it would never match, but
/// `::before` would be ignored as in "matching".
///
/// It's required for all the selectors you match using this mode to have a
/// pseudo-element.
ForStatelessPseudoElement,
}
/// The mode to use when matching unvisited and visited links.
#[derive(PartialEq, Eq, Copy, Clone, Debug)]
pub enum VisitedHandlingMode {
/// All links are matched as if they are unvisted.
AllLinksUnvisited,
/// A element's "relevant link" is the element being matched if it is a link
/// or the nearest ancestor link. The relevant link is matched as though it
/// is visited, and all other links are matched as if they are unvisited.
RelevantLinkVisited,
}
/// Which quirks mode is this document in.
///
/// See: https://quirks.spec.whatwg.org/
#[derive(PartialEq, Eq, Copy, Clone, Hash, Debug)]
pub enum QuirksMode {
/// Quirks mode.
Quirks,
/// Limited quirks mode.
LimitedQuirks,
/// No quirks mode.
NoQuirks,
}
impl QuirksMode {
#[inline]
pub fn classes_and_ids_case_sensitivity(self) -> CaseSensitivity {
match self {
QuirksMode::NoQuirks |
QuirksMode::LimitedQuirks => CaseSensitivity::CaseSensitive,
QuirksMode::Quirks => CaseSensitivity::AsciiCaseInsensitive,
}
}
}
/// Data associated with the matching process for a element. This context is
/// used across many selectors for an element, so it's not appropriate for
/// transient data that applies to only a single selector.
#[derive(Clone)]
pub struct MatchingContext<'a> {
/// Output that records certains relations between elements noticed during
/// matching (and also extended after matching).
pub relations: StyleRelations,
/// Input with the matching mode we should use when matching selectors.
pub matching_mode: MatchingMode,
/// Input with the bloom filter used to fast-reject selectors.
pub bloom_filter: Option<&'a BloomFilter>,
/// Input that controls how matching for links is handled.
pub visited_handling: VisitedHandlingMode,
/// Output that records 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.)
pub relevant_link_found: bool,
/// The quirks mode of the document.
pub quirks_mode: QuirksMode,
}
impl<'a> MatchingContext<'a> {
/// Constructs a new `MatchingContext`.
pub fn new(matching_mode: MatchingMode,
bloom_filter: Option<&'a BloomFilter>,
quirks_mode: QuirksMode)
-> Self
{
Self {
relations: StyleRelations::empty(),
matching_mode: matching_mode,
bloom_filter: bloom_filter,
visited_handling: VisitedHandlingMode::AllLinksUnvisited,
relevant_link_found: false,
quirks_mode: quirks_mode,
}
}
/// Constructs a new `MatchingContext` for use in visited matching.
pub fn new_for_visited(matching_mode: MatchingMode,
bloom_filter: Option<&'a BloomFilter>,
visited_handling: VisitedHandlingMode,
quirks_mode: QuirksMode)
-> Self
{
Self {
relations: StyleRelations::empty(),
matching_mode: matching_mode,
bloom_filter: bloom_filter,
visited_handling: visited_handling,
relevant_link_found: false,
quirks_mode: quirks_mode,
}
}
}
/// Holds per-element data alongside a pointer to MatchingContext.
pub struct LocalMatchingContext<'a, 'b: 'a, Impl: SelectorImpl> {
/// Shared `MatchingContext`.