proxyquire/examples/async/foo.js

Proxies nodejs require in order to allow overriding dependencies during testing.

var fs = require('fs')

module.exports.filesAllCaps = function (dir, cb) {
  fs.readdir(dir, function (err, files) {
    if (err) cb(err)
    else {
      cb(
        null
        , files.map(function (f) { return f.toUpperCase() })
      )
    }
  })
}