Resolve #290 to inherit rubocop config from a gem.

[jhansche]

The config directive should be in Hash format, with the gem_name
as the key, and the relative_path_to_config as the value. Ex:

inherit_from: .rubocop_todo.yml

inherit_gem:
    cucumber: config/rubocop.yml
    mygem: path/to/my/shared/rubocop.yml

If the gem is not installed, a warning is emitted, but execution
continues without the gem's config.

[jhansche]

Working on the Ruby 1.9.3 failures. And I'll add a test for it as well

[bbatsov]

Apart from the commit message and the missing changelog the PR looks reasonable to me. @jonas054 what do you think?

[jonas054]

If hash['inherit_from'] already contains a string, e.g. .rubocop_todo.yml, this will concatenate to that string.

[jonas054]

Super cool feature! I found one bug.

[jhansche]

@bbatsov

Apart from the commit message

What specifically about the commit message is problematic? Would you prefer that I rewrite the commit message and/or amend the commit with all changes squashed (instead of keeping the chain of 3 commits once I fix Jonas's bug)?

@jonas054 Nice find.. Just tested and confirmed that it fails with the String (instead of Array) yaml syntax. I'll definitely clean it up to make it more explicit.

[jhansche]

@bbatsov

Offenses:
lib/rubocop/config_loader.rb:12:3: C: Class has too many lines. [148/147]
  class ConfigLoader
  ^^^^^
626 files inspected, 1 offense detected

Any suggestions for dropping 1 line from this class? 🎱

[bbatsov]

Any suggestions for dropping 1 line from this class?

You can just increase to max class length.

Regarding the commit message - the title should not end with a .. Apart from that it looks OK.

[bbatsov]

I also think it'd be a good idea to mention this feature somewhere in the README, otherwise most people will likely miss it.

[jhansche]

@bbatsov Thanks! I've updated the max class length, fixed the trailing commit summary punctuation, and added a blurb to the README.

[jonas054]

I don't see why we should warn and continue when a config file from a gem can't be found. We should fail just like when a file listed in inherit_from can't be found.

[jhansche]

I don't see why we should warn and continue when a config file from a gem can't be found.

The main reason I went this route is for cases when you might need to run rubocop without first installing all dependencies. Granted, specifying inherit_gem may imply that running rubocop is dependent upon having that gem installed, so maybe in that case failing is the right approach... ¯_(ツ)_/¯

I don't mind either way. I'll make it fail instead of warning, if that is the consensus?

[bbatsov]

I don't mind either way. I'll make it fail instead of warning, if that is the consensus?

Yeah, that would probably be best.

[jhansche]

Sounds good -- done!

[jhansche]

Fixing the rspec test...