1131 fix deprecation warning for dirty attributes for rails > 5

[Marinlemaignan]

Resolves #1131

[MaicolBen]

Seems coherent with https://github.com/plataformatec/devise/blob/dac90eeb80ac351697e0a8d1bda9d1697c7b7078/lib/devise/models/database_authenticatable.rb#L182

[zachfeldman]

Thanks for the contribution @Marinlemaignan !

[dks17]

    if Rails::VERSION::MAJOR <= 5
      encrypted_password_changed? &&
      DeviseTokenAuth.remove_tokens_after_password_reset
    else
      saved_change_to_encrypted_password? &&
      DeviseTokenAuth.remove_tokens_after_password_reset
    end

It looks like in the else block is dead code because of expression Rails::VERSION::MAJOR <= 5 always return true for supported version 4 and 5? Else block is executed when major rails version is 6 or higher.

@Marinlemaignan in the header of the issue you used strict comparison > 5. Did you test it against rails 6?

@MaicolBen what do you think?

[MaicolBen]

Yeah, I would change it to Rails::VERSION <= 5.0 , good discovery!

[dks17]

1. Method saved_change_to_attribute? was introduced in ActiveRecord since 5.1 version.
2. Version checking should be put outside of the should_remove_tokens_after_password_reset? method. Like the code you linked above.
3. Mongoid doesn't support saved_change_to_attribute? method. I think be better define the should_remove_tokens_after_password_reset? method into mongoid_support and active_record_support concerns. In active_record_support concern you may useActiveRecord constant for version checking (didn't check) or Devise constant.