Latest version of @csstools/css-syntax-patches-for-csstree causes test failures

[domenic]

If you update package.json from ^1.0.14 to ^1.0.20, and do npm install && npm test, you get test failures.

I'll pin it at 1.0.14 for now.

@asamuzaK any ideas? (Fixing this is another good example of a single small PR.)

[tyrasd]

I took a quick look: the failing tests are all related to the fact that a percent value is used within the rect value of a clip property. Now, the definition of the clip property in the css masking level 1 working draft defines the rect values to be of either a <length> or auto. Note the absence of the <percentage>. Interestingly this differs from the definition of rect() values in the css-shapes level 2.

I'll pin it at 1.0.14 for now.

Unfortunately, this breaks other parts of the CSS parsing, see e.g. csstools/postcss-plugins#1703 which was fixed by passing through an upstream fix for an incorrect section in the css specs (w3c/csswg-drafts#13001). ¹

I would argue that having tests that rely on volatile parts of the CSS specifications that have not yet made it out of the working draft status is maybe not ideal, and especially so when the property in question has been marked as deprecated for more than 10 years.

Footnotes

1. We had been (and are now again) affected by this in https://github.com/openstreetmap/iD/pull/11659/ ↩