RuboCop 0.9 is finally out! This was one of our most ambitious releases - over a month of work, ~250 commits, lots of new cops and features and a lot less bugs (OK, I’m not sure about this, but I sincerely hope it’s true). Here’s the highlights.
This is a big deal! Prior to 0.9, RuboCop piggybacked on MRI’s
-wc to find syntax errors and lint warnings. Obviously apart from
being unportable - this wasn’t particularly fast (spawning processes
never is) either.
That’s no longer the case - errors are now reported directly by Parser and we’ve reimplemented MRI’s linting in pure Ruby into RuboCop itself. Now you’ll get the same errors and warnings on MRI, JRuby and Rubinius. And to top it off - we’ve added much nicer warning messages and we report even column information for those (MRI doesn’t). This brings me to the next point.
All RuboCop diagnostics now feature column information as well. Now you’ll be able to jump to a problem in your code even faster. But that’s not all…
We’ve introduced the concept of formatters (similar the to RSpec
formatter concept) and we’ve bundled a few formatters. We’ve also
changed the default output format - it now pretty similar to
and features extra context information:
spec/models/authentication_spec.rb:12:44: W: `-' interpreted as argument prefix }.to change(Authentication, :count).by -1 ^
Pretty sure most of you will love this
rubocop -a will now correct certain problems automatically. This
feature is alpha quality and just a few cops have support for it right
now. It goes without saying that you shouldn’t use it on projects not under
version control (who doesn’t use version control?) and without
an excellent test suite (that you undoubtedly have).
rubocop -R will run additional Rails specific code checks. This
feature is also alpha at this point (meaning there’s just one Rails
specific check at this point).
The Road to 1.0
We plan 1.0 to be the next RuboCop major release. No new features are in the pipeline for 1.0 - we already have so many features that require extra work and polish anyways. If all goes well expect 1.0 by summer’s end with:
- performance optimizations
- refined formatters
- enhanced auto-correction support
- lots of Rails specific checks
I hope you’ll enjoy RuboCop 0.9. For the gory details, please take a look at the epic Changelog.