RESOLVED FIXED Bug 242775
shorthand serialization for background and mask should not include "initial" in the middle of the value 
https://bugs.webkit.org/show_bug.cgi?id=242775
Summary shorthand serialization for background and mask should not include "initial" ...
Cameron McCormack (:heycam)
Reported 2022-07-14 16:25:24 PDT
For example: <!DOCTYPE html> <style> div { background: none; background-position: initial; } </style> <pre id=log></pre> <script> log.textContent = "background: " + document.styleSheets[0].cssRules[0].style.getPropertyValue("background"); </script> This outputs "background: none initial initial", which is not valid.
Attachments
Add attachment proposed patch, testcase, etc.
Radar WebKit Bug Importer
Comment 1 2022-07-21 16:26:16 PDT
<rdar://problem/97405629>
Darin Adler
Comment 2 2022-11-14 12:11:18 PST
There is a straightforward way to make sure we don’t serialize any shorthands when one of the longhands has a keyword like "initial". I wrote the code for it and it’s super-simple. But a prerequisite for doing that is that we have to stop setting longhands to "initial" as a side effect of *using* a shorthand. Otherwise, we’ll be getting the empty string way too often. That means we probably need to fix bug 244657 *before* fixing this one.
Tim Nguyen (:ntim)
Comment 3 2022-11-14 13:32:12 PST
Does removing `case CSSPropertyBackground:` from the `canUseShorthandForLonghand` blocklist in StyleProperties help?
Darin Adler
Comment 4 2022-11-21 10:35:13 PST
It does not fix this problem, no, but it should be done for other reasons.
Darin Adler
Comment 5 2022-12-01 07:51:54 PST
Pull request: https://github.com/WebKit/WebKit/pull/7025
EWS
Comment 6 2022-12-06 12:55:13 PST
Committed 257429@main (a0488d1bf07c): <https://commits.webkit.org/257429@main> Reviewed commits have been landed. Closing PR #7025 and removing active labels.
Note You need to log in before you can comment on or make changes to this bug.