We want to make the output match the yml expectations

[krainboltgreene]

I want this change so that if I need to modify a cop I can use
—show-cop, find the right one, and then copy/paste the body into the
yml and do no extra work to format it for YAML documents.

You'll notice the failing test. I attempted to fix it but the test is really clunky and apparently iterates through a series of expectations. One of these expectations fails in a way that doesn't make sense (expecting the wrong cop description).

[coveralls]

Coverage decreased (-0.03%) when pulling 62c1d04 on krainboltgreene:improving-show-cop-output into 0d7161c on bbatsov:master.

[bbatsov]

Makes sense to output the info in yml format. @jonas054 Would you have a look the problematic test?

[bbatsov]

Btw, @jonas054, seems to me it might be a good idea for us to add --show-cop Cop option as well for people who want to see information just for a particular cop. Or maybe we can adjust -show-cops to receive a list of cop names as params - say --show-cops Tab StringLiteral MethodName. With no arguments we'd keep the existing behaviour.

[jonas054]

Yes, I'll look at this!

[jonas054]

If we want to make it possible to copy and paste --show-cops output into a configuration file, we should make sure the output is YAML. Today we have

 - CollectionMethods
    - Description: Preferred collection methods.
    - Enabled: true
    - PreferredMethods: {"collect"=>"map", "collect!"=>"map!", "inject"=>"reduce", "detect"=>"find", "find_all"=>"select"}
    - SupportsAutoCorrection: true

The commit in this PR changes it to:

CollectionMethods:
  Description: Preferred collection methods.
  Enabled: true
  PreferredMethods: {"collect"=>"map", "collect!"=>"map!", "inject"=>"reduce", "detect"=>"find", "find_all"=>"select"}
  SupportsAutoCorrection: true

This is still not YAML. The values are on Ruby literal format. I propose to change the output to something very similiar to what we have in our config files:

CollectionMethods:
  Description: Preferred collection methods.
  Enabled: true
  PreferredMethods:
    collect: map
    collect!: map!
    inject: reduce
    detect: find
    find_all: select
  SupportsAutoCorrection: true

One other option is to make a more compact format where all values are output as JSON (which is a subset of YAML). This is a middle of the road solution that doesn't make anybody happy, IMO.

CollectionMethods:
  Description: "Preferred collection methods."
  Enabled: true
  PreferredMethods: {"collect":"map","collect!":"map!","inject":"reduce","detect":"find","find_all":"select"}
  SupportsAutoCorrection: true

@krainboltgreene @bbatsov @yujinakayama What do yo think?

[bbatsov]

I think it would be best if we output YAML to match the actual configuration format.