$ decaffeinate src/lib/taskgroup.coffee
fs.js:1613
  options = Object.create(options || {});
                   ^
TypeError: Object prototype may only be an Object or null: utf8
    at Function.create (native)
    at new ReadStream (fs.js:1613:20)
    at fs.createReadStream (fs.js:1602:10)
    at processPath (/Users/balupton/.nvm/versions/io.js/v1.6.1/lib/node_modules/decaffeinate/lib/cli.js:72:19)
    at processNext (/Users/balupton/.nvm/versions/io.js/v1.6.1/lib/node_modules/decaffeinate/lib/cli.js:82:7)
    at runWithPaths (/Users/balupton/.nvm/versions/io.js/v1.6.1/lib/node_modules/decaffeinate/lib/cli.js:88:3)
    at run (/Users/balupton/.nvm/versions/io.js/v1.6.1/lib/node_modules/decaffeinate/lib/cli.js:29:5)
    at Object.<anonymous> (/Users/balupton/.nvm/versions/io.js/v1.6.1/lib/node_modules/decaffeinate/bin/decaffeinate:3:22)
    at Module._compile (module.js:410:26)
    at Object.Module._extensions..js (module.js:428:10)