# File lib/omniauth/strategies/ldap.rb, line 62
      def filter(adaptor)
        if adaptor.filter and !adaptor.filter.empty?
          username = Net::LDAP::Filter.escape(@options[:name_proc].call(request['username']))
          Net::LDAP::Filter.construct(adaptor.filter % { username: username })
        else
          Net::LDAP::Filter.equals(adaptor.uid, @options[:name_proc].call(request['username']))
        end
      end