Do not clobber existing directories when configuring workspace dir

[kytrinyx]

When configuring the nextercism CLI for the first time (e.g. when workspace_dir in the config is blank), then we should verify that the workspace directory does not exist before setting a default. If it does, then we should exit with an error message saying that the directory already exists, and that if that's the correct directory, please call the command again, explicitly adding --directory="...".

We can print the full command for them to copy (including the token, which they just gave us).

[NobbZ]

Why is it not allowed to exist?

I'm using exerercism across several computers and synchronise the exercism folder by a third party tool. Why am I not allowed to do that anymore with nextercism?

Or why do I have to configure nextercism before synchronising the folder for the first time?

[kytrinyx]

Why is it not allowed to exist?

It's allowed, I just don't want us to accidentally use a directory that someone is using for (for example) contributing to Exercism.

I think we can do things to make your use case simpler, if it's painful.

[NobbZ]

I think a simple --force flag would be sufficient for my usecase.

[kytrinyx]

@NobbZ to clarify, this will only complain if both of the following are true:

a) the default directory exists already, and
b) no --workspace flag is passed

If you pass the --workspace flag explicitly, we assume that you know what you're doing. Would this be enough, or is there still a case where you need --force?

[NobbZ]

No, that's totally fine. When I read the proposal the first time I understood it as to not allow existing folders at all.

[kytrinyx]

When I read the proposal the first time I understood it as to not allow existing folders at all.

Oooh! Yeah, that would be silly and impractical :)