Bug 242328 – Wrong specificity of :has() pseudo-classes

• Status: RESOLVED
• Resolution: FIXED
• Component: CSS

[Ilya Streltsyn]

The specificity of the selector containing the `:has()` pseudo-class appears to be higher than the specificity of the selector with the same number of classes without it.
 
Steps to reproduce:

1. Navigate to the https://codesandbox.io/s/peaceful-edison-8kcudt?file=/index.html demo
2. Check the background color of the three cards
3. Open Web Inspector
4. Inspect computed styles of the first card

Expected results:

The first card is light green, the next two cards are light blue.
Web Inspector shows that the rule for the `.card.card--green` selector has overridden the rule for the `.card:has(.title)` selector (as having the same specificity but coming later in the code).

Actual results:

All three cards are light blue.
Web Inspector shows that the rule for the `.card:has(.title)` selector has overridden the rule for the `.card.card--green` selector.


There is a closed bug https://bugs.webkit.org/show_bug.cgi?id=235351 regarding the same topic, so it might be a regression.

Both stable Safari 15.5 and Safari TP 148 display the same behavior. Chrome 103 with the "Experimental Web Platform features" flag enabled displays expected results.

[Tim Nguyen (:ntim)]

:is() & :not() have the same issue.

[Antti Koivisto]

(In reply to Tim Nguyen (:ntim) from comment #1)
> :is() & :not() have the same issue.

I see the :has() issue but I'm not seeing that. Please file a separate bug with a test case.

[Antti Koivisto]

Created attachment 460675 [details]
Patch

[EWS Watchlist]

This patch modifies the imported WPT tests. Please ensure that any changes on the tests (not coming from a WPT import) are exported to WPT. Please see https://trac.webkit.org/wiki/WPTExportProcess

[EWS]

Committed 252140@main (7af18efe7e89): <https://commits.webkit.org/252140@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 460675 [details].

[Radar WebKit Bug Importer]

<rdar://problem/96449421>