class Sass::Tree::Visitors::Convert

def visit_children(parent)
  @tabs += 1
  return @format == :sass ? "\n" : " {}\n" if parent.children.empty?
  (@format == :sass ? "\n" : " {\n") + super.join.rstrip + (@format == :sass ? "\n" : " }\n")
ensure
  @tabs -= 1
end