class Capybara::Selector::CSSBuilder

def attribute_conditions(attributes)
  attributes.map do |attribute, value|
    case value
    when XPath::Expression
      raise ArgumentError, "XPath expressions are not supported for the :#{attribute} filter with CSS based selectors"
    when Regexp
      Selector::RegexpDisassembler.new(value).substrings.map do |str|
        "[#{attribute}*='#{str}'#{' i' if value.casefold?}]"
      end.join
    when true
      "[#{attribute}]"
    when false
      ':not([attribute])'
    else
      if attribute == :id
        "##{::Capybara::Selector::CSS.escape(value)}"
      else
        "[#{attribute}='#{value}']"
      end
    end
  end.join
end

def class_conditions(classes)
  case classes
  when XPath::Expression
    raise ArgumentError, 'XPath expressions are not supported for the :class filter with CSS based selectors'
  when Regexp
    strs = Selector::RegexpDisassembler.new(classes).substrings
    strs.map { |str| "[class*='#{str}'#{' i' if classes.casefold?}]" }.join
  else
    cls = Array(classes).group_by { |cl| cl.start_with? '!' }
    (cls[false].to_a.map { |cl| ".#{Capybara::Selector::CSS.escape(cl)}" } +
    cls[true].to_a.map { |cl| ":not(.#{Capybara::Selector::CSS.escape(cl.slice(1..-1))})" }).join
  end
end