Install missing tools

[abitrolly]

I know it is probably not the goal of lefthook, but.. sometimes lefthook fails for new users, because they don't have tools installed.

https://gitlab.com/gitlab-org/gitlab-development-kit/-/issues/1584

Even if it is not the goal, discussing what is available today to cover this scenario would be beneficial. sg setup is doing this - checking dependencies and installing them.

1. asdf - requires shell to be reloaded? PostgreSQL is installed from source, takes an hour.
2. nix - complicated. Not clear how to switch versions for testing.
3. brew - not clear how to pin versions.
4. whalebrew - looks promising, might be a way to go

The best solution is to provide tools in isolated environment, so whalebrew might be the best answer. Need to check that though. I don't like when SDKs are making intrusive changes to my system. These are sometimes hard to debug, so it is nice to limit all modifications only to the project lefthook is installed in.

[mrexox]

Hey! I got your point. I think the most natural way is to use Gemfile or package.json to handle dependencies (and lefthook binary also).

But there is a feature lefthook supports for lefthook-local.yml - {cmd} template. This allows to wrap the command from lefthook.yml into any other command, e.g., docker run. So, it might be a workaround - keep all dependencies in a special Docker environment and use it for running lefthook (and maybe other development tasks. See dip utility, which provides a tool for dockerized development environment.)

P.S.

There is an option called fail_text which can be used for the installation instructions, like please make sure you have <tool> installed or install it with a "asdf install ..." command. At least some information about dependencies might be helpful.

P.P.S.

And after all you can use scripts which check that the required tools are installed or install the specific version.