Multiple values in `src` property of `@font-face` rule not parsed correctly

[alexander-nitsche-governikus]

Using v8.4.0 with PHP 8.2.20:

When parsing

$cssContent = "@font-face {
    font-family: 'Open Sans';
    font-style: italic;
    font-weight: 300;
    font-display: swap;
    src: url('../fonts/open-sans-italic-300.woff2') format('woff2'),
         url('../fonts/open-sans-italic-300.ttf') format('truetype');
}";
$cssParser = new \Sabberworm\CSS\Parser($contentCss);
$cssDocument = $cssParser->parse();
$fontFaceSrcList = $cssDocument->getContents()[0]->getRulesAssoc()['src']->getValue()->getListComponents();

the resulting $fontFaceSrcList contains 3 instead of 2 components:

[JakeQZ]

Hi @alexander-nitsche-governikus, thanks for the detailed report, which clearly shows the 'actual behaviour'.

It looks like the parser is treating 'comma' as a higher-precendence 'operator' than 'space' for this property, whereas it should be vice-versa.

IIRC, I've seen in the code base a list of separators/operators in precedence order being passed to a property parsing function (method). So hopefully the fix would be as simple as providing the correct precedence for this property. For example, box-shadow would require splitting at commas before spaces (and hopefully is already parsed correctly). @sabberworm, does this seem probably about right?

[sabberworm]

Yes, passing in a non-standard list separator precedence order for src inside @font-family should do the trick.

I’m worried we don’t know enough about the context to actually determine we’re inside @font-family. On the other hand, src currently only exists inside @font-family, so that shouldn’t really be a problem. And it’s likely future src properties introduced into CSS will be parsed the same way as the one inside @font-family.

[JakeQZ]

Yes, passing in a non-standard list separator precedence order for src inside @font-family should do the trick.

Indeed it does. But it seems the same trick is going to be required for many other properties, for which I've added #791. I also wonder why / is in the default list of separators. @sabberworm, do you recall which properties this was needed for?

[alexander-nitsche-governikus]

Thanks a lot guys.