Fixing problem when parameter's key is nil in Rack

rack_keyspace_bugfix.rb

#
# => This is a monkey patch to fix the problem with nil key params in rack 1.4.1
# => It already be solved by Rack team but it will be release in rack 1.4.2
# => https://github.com/rack/rack/pull/329
#


module Rack::Utils

  def self.parse_query(qs, d = nil)
    params = KeySpaceConstrainedParams.new

    (qs || '').split(d ? /[#{d}] */n : DEFAULT_SEP).each do |p|
      k, v = p.split('=', 2).map { |x| unescape(x) }
      next unless k || v

      if cur = params[k]
        if cur.class == Array
          params[k] << v
        else
          params[k] = [cur, v]
        end
      else
        params[k] = v
      end
    end

    return params.to_params_hash
  end

  class KeySpaceConstrainedParams

    def []=(key, value)
      @size += key.size if key && !@params.key?(key)
      raise RangeError, 'exceeded available parameter key space' if @size > @limit
      @params[key] = value
    end

  end
end