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@nrz/dss-parser

v1.0.0

Published

The Dependency Selector Syntax (DSS) parser

Readme

@nrz/dss-parser

The Dependency Selector Syntax parser used by the nrz client.

Uses postcss-selector-parser to parse a selector string into an AST.

Usage

import { parse } from '@nrz/dss-parser'

// Parse a selector string into an AST
const ast = parse(':root > *')

Validation

parse() throws a SyntaxError on invalid DSS, with cause.code EQUERY and the offending input in cause.found. Rejected:

  • malformed syntax, e.g. :outdated(, [name=
  • empty / whitespace-only queries and empty selectors (#a,, :not())
  • unknown pseudo-classes, combinators and attribute operators
  • dangling combinators, e.g. :root >, > >
  • bare words, strings, empty ids / attributes, e.g. foo, .dev, "foo", #, []
  • a part selector (:skill()) with an empty argument, not ending a top-level selector, or inside :not()/:is()/:has()

:is() arguments are a forgiving list: only the bare words group and the part selector rule apply there.

Pass { loose: true } to skip the DSS checks (malformed syntax still throws):

parse('#a, :unknown', { loose: true }) // no throw

Supported names are exported as pseudoClassNames, combinatorNames, attributeOperatorNames and partPseudoNames.