Bug 220862 – REGRESSION (r271584): Hovering slowly over and out of "Top 100" items on liberation.fr does not restore animated state

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

[Antoine Quint]

Created attachment 418151 [details]
Screen recording

Steps to reproduce:

1. Open https://www.liberation.fr/
2. Wait for the page to finish loading and for only 5 items to show under "Top 100" near the center of the page
3. Hover slowly over those 5 items

Notice how, as in the attached screen recording, the items don't revert back to their pre-animated state after hovering out.

I only managed to reduce the failed to this range:

http://trac.webkit.org/log/trunk/?mode=follow_copy&rev=271601&stop_rev=271568

Out of this range, r271584, the fix for bug 220711, seems the most likely since it's related to :hover.

[Radar WebKit Bug Importer]

<rdar://problem/73501684>

[Antti Koivisto]

Ah yes, there is a logic error in the optimization where we fail to invalidate descendants losing hover/active in some complex cases.

[Antti Koivisto]

Created attachment 418384 [details]
patch

[Antti Koivisto]

Created attachment 418392 [details]
patch

[Antti Koivisto]

Created attachment 418409 [details]
patch

[Simon Fraser (smfr)]

Comment on attachment 418409 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=418409&action=review

> Source/WebCore/dom/Document.cpp:7234
> +        Style::PseudoClassChangeInvalidation styleInvalidation(*elementsToClearActive.last(), CSSSelector::PseudoClassActive, Style::InvalidationScope::Descendants);
> +        for (auto& element : elementsToClearActive)
> +            element->setActive(false, false, Style::InvalidationScope::SelfChildrenAndSiblings);

Maybe share these almost-duplicate chunks with some lambdas?

[Antti Koivisto]

> Maybe share these almost-duplicate chunks with some lambdas?

It seemed to end up looking messy since there is a bunch of varying parameters. But I'll take another look.

[EWS]

Committed r271930: <https://trac.webkit.org/changeset/271930>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 418409 [details].

[Simon Fraser (smfr)]

Landed early because it fixed other bugs that were blocking internal Apple work.