function extractCwdArg(args) {
        for (let i = 0, I = args.length; i < I; ++i) {
          const arg = args[i]
          if (arg === '--') {
            return null
          } else if (arg === '--cwd') {
            return args[i + 1]
          }
        }
        return null
      }
`Option` is missing an argument, but received `flag` or nothing.

@param {String} option
@param {String} flag
@api private