Include execution `env` option?

[michaeljones]

I realise this project is probably not getting much attention at the moment which is totally fine & understandable.

I just wanted to suggest that it might benefit from taking an env option like child_process.exec does so that someone can say "does this command exist given this environment." I'm in the position of needing that at the moment and will have to look around for other options.

I guess it is both a relatively niche feature and also something that would fit quite naturally into the module?

[mathisonian]

Thanks for raising this @michaeljones. I don't have the bandwidth to add at the moment, but I do think its a good feature to have and would accept a PR for it if anyone wants to add.

[michaeljones]

Thanks for the reply. Very understandable. I might take a look at some point and will open a PR if I do.