Parselly

Pure Ruby CSS selector parser.

Installation

gem 'parselly'

bundle install

Or install it directly:

gem install parselly

Requires Ruby 2.7 or newer.

Usage

require 'parselly'

ast = Parselly.parse('article#main.content[data-state="open"] > a:hover')

ast.ids
#=> ["main"]

ast.attributes
#=> [{ name: "data-state", operator: "=", value: "open" }]

ast.pseudo_class_names
#=> ["hover"]

ast.specificity
#=> [1, 3, 2]

Strict parsing raises Parselly::LexError or Parselly::SyntaxError for invalid selectors:

Parselly.parse('div >')

Use tolerant mode when you want a Parselly::ParseResult instead:

result = Parselly.parse('div >', tolerant: true)

result.success?
#=> false

result.errors.first[:message]
#=> "Parse error: unexpected $end '' at 1:6"

Use Parselly.sanitize to escape text for a CSS identifier:

Parselly.sanitize('1st item')
#=> "\\31 st\\ item"

Development

bin/setup
bundle exec rake

License

MIT