style: Cleanup selector-matching for nested pseudo-elements, match ::slotted correctly when there's no selector before it, and add tests.

D29542 fixed the bogus checks that was making nested pseudo-elements match
author rules. This adds tests and ends up being just a cleanup, though as it
turns out we it also fixes an issue with ::slotted() matched from
Element.matches.

Differential Revision: https://phabricator.services.mozilla.com/D27529
This commit is contained in:
Emilio Cobos Álvarez 2019-05-24 01:09:15 +00:00
parent 272d9758d7
commit 43444db8a8
9 changed files with 35 additions and 38 deletions

View file

@ -47,9 +47,13 @@ pub trait Element: Sized + Clone + Debug {
///
/// This is guaranteed to be called in a pseudo-element.
fn pseudo_element_originating_element(&self) -> Option<Self> {
debug_assert!(self.is_pseudo_element());
self.parent_element()
}
/// Whether we're matching on a pseudo-element.
fn is_pseudo_element(&self) -> bool;
/// Skips non-element nodes
fn prev_sibling_element(&self) -> Option<Self>;