# File lib/sass/tree/visitors/perform.rb, line 216
  def visit_import(node)
    if path = node.css_import?
      return Sass::Tree::CssImportNode.resolved("url(#{path})")
    end
    file = node.imported_file
    handle_import_loop!(node) if @stack.any? {|e| e[:filename] == file.options[:filename]}

    begin
      @stack.push(:filename => node.filename, :line => node.line)
      root = file.to_tree
      Sass::Tree::Visitors::CheckNesting.visit(root)
      node.children = root.children.map {|c| visit(c)}.flatten
      node
    rescue Sass::SyntaxError => e
      e.modify_backtrace(:filename => node.imported_file.options[:filename])
      e.add_backtrace(:filename => node.filename, :line => node.line)
      raise e
    end
  ensure
    @stack.pop unless path
  end