[jwinter]

This exists and is what Hound is built on. Rubocop runs lint checks against your Ruby code: https://github.com/bbatsov/rubocop/ . The Emacs integration is great; it highlights failures in place. Hound looks interesting, but having Emacs/Vim integration gives you a tighter feedback loop, so you don't have to wait until Pull Request time to discover these issues.

[salbertson]

RuboCop is great, but one benefit of Hound is it only checks code that has changed. Retroactively enforcing code style is usually a bad idea.

[gknoy]

You can also use linting tools as a build validation step (ours are invoked via things like `make myapp.pep8test`). These can also then be invoked yourself before making a commit. As jwinter says, this really tightens the loop when fixing trivial errors.

Almost all of the tools are very configurable in terms of which warnings/errors you want to ignore (e.g., let our max line length be 120 instead of 80), and give pretty good feedback (line numbers, exact error).

Another great benefit is that you have a neutral arbiter of what's the style for your codebase, which helps avoid ruffled feathers.

[rubiquity]

I figured such a tool must exist. Thank you for helping me remain lazy. I agree about having the tighter feedback loop.

I'm hoping to create a git filter that stops the commit from happening if there are style guide violations.