     ###
 
     append_query_string = (url, args = {}) ->
-      url += '?'
-      for k, v of args
-        url += "#{k}=#{v}&"
-      if url[url.length - 1] == '&'
-        url = url.substring(0, url.length - 1)
-      return url
+      "#{url}?#{querystring.stringify(args)}"

_          = require 'lodash'
W          = require 'when'
S          = require 'string'
path       = require 'path'
contentful = require 'contentful'
pluralize  = require 'pluralize'
RootsUtil  = require 'roots-util'

errors =
  no_token: 'Missing required options for roots-contentful. Please ensure

     * @return {String} - URL string for the asset
    ###

    asset_view_helper = (asset = {}, opts) ->
      asset.fields ?= {}
      asset.fields.file ?= {}
      url = asset.fields.file.url
      if opts then append_query_string(url, opts) else url

