Validator proposal: same_as

[glaucocustodio]

Hi folks, I just added a custom validator (same_as) to my app and I would like to know whether it would be welcome to grape itself:

resources :passwords do
  params do
    requires :current_password, allow_blank: false
    requires :password, allow_blank: false
    requires :password_confirmation, allow_blank: false, same_as: :password
  end
  post do
  end
end

Thanks.

[myxoh]

Can you think of any other example in which it would be useful other that the password password_confirmation?
I've spent some time trying to think of alternative use cases and I'm having a hard time. If there aren't any it seems to be as a bit of an overkill to have a validator for just one use case, especially as there are plenty of libraries that handle this specific validation at the model level (arguably it'd be better at a param level, but seems to niche)

I'll let @dblock make the final call

[glaucocustodio]

I can only think in confirmation cases like email and password. Anyway I would say it is worth to have common validators built-in like this one and some others like length. Those are very small, isolated (one file) and nice to have.

[dblock]

I like it. Would merge a PR.

[glaucocustodio]

I am closing because it was implemented on PR #1850.