const promiseToCallback = require('promise-to-callback')
const noop = function () {}
/**
* A generator that returns a function which, when passed a promise, can treat that promise as a node style callback.
* The prime advantage being that callbacks are better for error handling.
*
* @param {Function} fn The function to handle as a callback
* @param {Object} context The context in which the fn is to be called, most often a this reference
*/
module.exports = function nodeify (fn, context) {
return function () {
const args = [].slice.call(arguments)
const lastArg = args[args.length - 1]
const lastArgIsCallback = typeof lastArg === 'function'
let callback
if (lastArgIsCallback) {
callback = lastArg
args.pop()
} else {
callback = noop
}
promiseToCallback(fn.apply(context, args))(callback)
