DisabledByDefault doesn't appear to merge properly

[thommay]

given a config file:

inherit_gem:
  rubocop: config/default.yml

AllCops:
  DisabledByDefault: true

I'd expect all cops to be disabled, however the default set of cops is applied:

11:00 ~/code/rubocop % be bin/rubocop -c /Users/thom/work/chefstyle/config/chefstyle.yml /Users/thom/work/chefstyle -f simple
[...]
6 files inspected, 51 offenses detected

Removing the inherit_gem section correctly results in no cops being applied:

1:01 ~/code/rubocop % be bin/rubocop -c /Users/thom/work/chefstyle/config/chefstyle.yml /Users/thom/work/chefstyle -f simple
6 files inspected, no offenses detected

[thommay]

Rubocop from current git master:

11:08 ~/code/rubocop % be bin/rubocop -V                               [master]
0.35.1 (using Parser 2.2.3.0, running on ruby 2.2.3 x86_64-darwin15)

[jonas054]

This is what happens. You load configuration from the rubocop gem where AllCops:DisabledByDefault is false. This value is then overridden by your local setting DisabledByDefault: true. The default configuration is then merged with your user configuration, and since DisabledByDefault if true, the default configuration is disabled and your user configuration is enabled.

The thing you might have missed is that user configuration is everything in your .rubocop.yml, including configuration that you excplicitly inherit from, in this case from the rubocop gem. The default configuration is defined by config/default.yml in the rubocop you're running, which may or may not be the same as the gem. Either way, it's two configurations.

I think it better if we make rubocop fail when inherit_gem uses the rubocop gem, because it makes no sense to inherit that way. It only causes confusion.

[alexdowad]

OK, just pushed a commit which implements @jonas054's suggestion. Let's see what @bbatsov says about it.