Fix function-no-unknown false positives for unspaced operators against nested brackets

[romainmenke]

Which issue, if any, is this issue related to?

Closes #6582

Is there anything in the PR that needs further explanation?

This change migrates this rule from postcss-value-parser to @csstools/css-parser-algorithms.

[changeset-bot]

🦋 Changeset detected

Latest commit: 8cd0ee9

The changes in this PR will be included in the next version bump.

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stylelint	Patch

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[mattxwang]

I have one quick question, but other than that this looks good to me - glad to see that the @csstools packages are useful!

[mattxwang]

Since we've removed this check, is it possible that this rule will now flag errors for SASS/CSS-in-JS users? If so, I imagine that this might be slightly breaking for those users (and/or something we propagate to configs)?

(I could also be missing something about how SASS and CSS-in-JS play together with this rule, or with @csstools)

[romainmenke]

Good catch :)

module.exports = function isStandardSyntaxFunction(node) {
	// Function nodes without names are things in parentheses like Sass lists
	if (!node.value) {
		return false;
	}

	if (node.value.startsWith('#{')) {
		return false;
	}

	// CSS-in-JS interpolation
	if (node.value.startsWith('${')) {
		return false;
	}

	// CSS-in-JS syntax
	if (node.value.startsWith('`')) {
		return false;
	}

	return true;
};

None of those cases would be parsed as a FunctionNode by @csstools/css-parser-algorithms.

Only <ident><open-parenthesis> (e.g. foo() starts a function in standard CSS.

This behavior makes isFunctionNode the equivalent of isStandardSyntaxFunction.

is it possible that this rule will now flag errors for SASS/CSS-in-JS users?

no

[ybiquitous]

Thanks for the pull request. I've suggested a tiny refactoring, but this PR sounds good. 👍🏼

Because postcss-value-parser seems to stop maintenance, we may need to switch it to @csstools/css-tokenizer to reduce dependencies.

[ybiquitous]

LGTM 👍🏼