The cwd options must have a default value process.cwd()

[Delan1026]

cwd should have a default value: process.cwd(), if not, it will cause other related npm package run with errors! for example globby， egg-bin test depend on globby, const files = globby.sync(pattern) don't pass the options argument

[kevva]

It already has. But if another value is passed in it'll use that instead. I don't think it's this modules responsibility to fix that.

There's a PR open for checking that it's set correctly though #8.