class Sass::Tree::PropNode

def ==(other)
  self.class == other.class && name == other.name && value == other.value && super
end

def check!
  return unless @options[:property_syntax] && @options[:property_syntax] != @prop_syntax
  raise Sass::SyntaxError.new(
    "Illegal property syntax: can't use #{@prop_syntax} syntax when " +
    ":property_syntax => #{@options[:property_syntax].inspect} is set.")
end

def custom_property?
  name.first.is_a?(String) && name.first.start_with?("--")
end

def declaration(opts = {:old => @prop_syntax == :old}, fmt = :sass)
  name = self.name.map {|n| n.is_a?(String) ? n : n.to_sass(opts)}.join
  value = self.value.map {|n| n.is_a?(String) ? n : n.to_sass(opts)}.join
  value = "(#{value})" if value_needs_parens?
  if name[0] == ?:
    raise Sass::SyntaxError.new("The \"#{name}: #{value}\"" +
                                " hack is not allowed in the Sass indented syntax")
  end
  # The indented syntax doesn't support newlines in custom property values,
  # but we can losslessly convert them to spaces instead.
  value = value.tr("\n", " ") if fmt == :sass
  old = opts[:old] && fmt == :sass
  "#{old ? ':' : ''}#{name}#{old ? '' : ':'}#{custom_property? ? '' : ' '}#{value}".rstrip
end

def initialize(name, value, prop_syntax)
  @name = Sass::Util.strip_string_array(
    Sass::Util.merge_adjacent_strings(name))
  @value = Sass::Util.merge_adjacent_strings(value)
  @value = Sass::Util.strip_string_array(@value) unless custom_property?
  @tabs = 0
  @prop_syntax = prop_syntax
  super()
end

def invisible?
  !custom_property? && resolved_value.empty?
end

def pseudo_class_selector_message
  if @prop_syntax == :new ||
      custom_property? ||
      !value.first.is_a?(Sass::Script::Tree::Literal) ||
      !value.first.value.is_a?(Sass::Script::Value::String) ||
      !value.first.value.value.empty?
    return ""
  end
  "\nIf #{declaration.dump} should be a selector, use \"\\#{declaration}\" instead."
end

def value_needs_parens?
  return false if custom_property?
  root = value.first
  root.is_a?(Sass::Script::Tree::Operation) &&
    root.operator == :div &&
    root.operand1.is_a?(Sass::Script::Tree::Literal) &&
    root.operand1.value.is_a?(Sass::Script::Value::Number) &&
    root.operand1.value.original.nil? &&
    root.operand2.is_a?(Sass::Script::Tree::Literal) &&
    root.operand2.value.is_a?(Sass::Script::Value::Number) &&
    root.operand2.value.original.nil?
end