CSS :visited color taken on non-visited link when using CSS variables

• Component: CSS
• Status: RESOLVED FIXED

When setting colors for anchor tags using css-vars, the visited color in a css-variable override is taken even if other anchor tags on the same page (that are not using css-vars) don't exhibit the same behavior.

https://jsfiddle.net/rf1njobm/3/

The first link on the page gets its styles from a --link-color-visited variable. An identical anchor tag (with the same href) that doesn't use a variable (only raw colors) doesn't appear to be visited.

[Radar WebKit Bug Importer]

<rdar://problem/61800412>

[Tyler Wilcock]

Created attachment 408005 [details]
Patch

[Tyler Wilcock]

Created attachment 408018 [details]
Patch

[Darin Adler]

Comment on attachment 408018 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=408018&action=review

> Source/WebCore/style/StyleBuilder.cpp:190
> +    auto originalLinkMatch = m_state.m_linkMatch;

This won’t do the right thing if the "return" below is done after changing m_state.m_linkMatch.

We have a class SetForScope designed for this kind of thing, that could make sure we get that right.

[Tyler Wilcock]

Created attachment 408059 [details]
Patch

[Tyler Wilcock]

TIL of SetForScope, thanks Darin!  I think I've fixed it -- can you take another look?

[Darin Adler]

Comment on attachment 408059 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=408059&action=review

> Source/WebCore/style/StyleBuilder.cpp:43
>  #include "StylePropertyShorthand.h"
>  
> +#include <wtf/SetForScope.h>

WebKit coding style does not leave a space between these making it two paragraphs. But fine to land like this for now.

> Source/WebCore/style/StyleBuilder.cpp:220
> +            SetForScope<SelectorChecker::LinkMatchMask> scopedLinkMatchMutation(m_state.m_linkMatch, index);

Oh, looks like there is a better way to write it:

    auto scopedLinkMatchMutation = SetForScope(m_state.m_linkMatch, index);

That way we don’t have to write out the type. But fine to land like this for now.

[EWS]

Committed r266656: <https://trac.webkit.org/changeset/266656>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 408059 [details].