artesanias/node_modules/normalize-package-data/lib/make_warning.js

var util = require("util")
var messages = require("./warning_messages.json")

module.exports = function() {
  var args = Array.prototype.slice.call(arguments, 0)
  var warningName = args.shift()
  if (warningName == "typo") {
    return makeTypoWarning.apply(null,args)
  }
  else {
    var msgTemplate = messages[warningName] ? messages[warningName] : warningName + ": '%s'"
    args.unshift(msgTemplate)
    return util.format.apply(null, args)
  }
}

function makeTypoWarning (providedName, probableName, field) {
  if (field) {
    providedName = field + "['" + providedName + "']"
    probableName = field + "['" + probableName + "']"
  }
  return util.format(messages.typo, providedName, probableName)
}