fix: allow relative color syntax for rgb()

[SwetaTanwar]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request?

Fix eslint/css#235

What changes did you make? (Give an overview)

Allow relative color syntax for rgb() and rgba(), following syntaxes are now valid:

/* Relative values */
rgb(from green r g b / 0.5)
rgb(from #123456 calc(r + 40) calc(g + 40) b)
rgb(from hwb(120deg 10% 20%) r g calc(b + 200))
rgb(from hsl(0 100% 50%) r g b)
rgb(from hsl(0 100% 50% / 0.8) r g b / alpha)
rgb(from hsl(0 100% 50% / 0.8) r g b / 0.5)
rgb(from hsl(0 100% 50%) calc(r/2) calc(g + 25) calc(b + 175) / calc(alpha - 0.1))

Related Issues

Is there anything you'd like reviewers to focus on?

[coveralls]

Pull Request Test Coverage Report for Build 17358731850

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 98.618%

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Totals
Change from base Build 17211507538:	0.0%
Covered Lines:	11829
Relevant Lines:	11961

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💛 - Coveralls

[snitin315]

@SwetaTanwar Can you check the lint failure?

[SwetaTanwar]

@snitin315 Done.

[snitin315]

LGTM, thanks ⭐

@SwetaTanwar Let's also add a test case in the CSS repo once this patch is released.

[jaymarvelz]

@snitin315 I don’t understand how this was merged. Not only does it not address eslint/css#235 at all, but it also seems to be the wrong fix. Please revert and reopen the issue.

[SwetaTanwar]

I don’t understand how this was merged. Not only does it not address eslint/css#235 at all,

@jaymarvelz I think you are mistaken, this PR directly address the mentioned issue, I have added test cases here to verify that the PR fixes the issue eslint/css#247

[nzakas]

@jaymarvelz this comment was unproductive. If you believe there's something missing or a case that wasn't covered, please explain, don't just ask for a revert.

@snitin315 I would have liked the opportunity to review this PR before it was merged.

[nzakas]

@SwetaTanwar thanks for looking into this. It looks like you created your own entries in patch.json, and while that's part of the correct approach, we need to make sure we're using type definitions as they appear in the CSS specifications. Otherwise, it becomes difficult to track down updates as new specifications are incorporated.

The syntax you're using for rgb() and rgba() isn't quite correct (we shouldn't be including calc(), as one example), and there are more functions that support relative color syntax, too.

With apologies, I'm going to revert this PR so we can continue to work on the details. I've opened an issue explaining what needs to be done:
#82

[snitin315]

@SwetaTanwar @nzakas Apologies, I'll make sure to keep the PR open for a few days for further reviews.