v4.0.0 regression? Inside if proc, the updated_at is already updated

[gamov]

Given:

class ItemVariant < ActiveRecord::Base
  has_paper_trail :on => [:update, :destroy],
                  :class_name => 'ItemVariantVersion',
                  if: proc {|t| t.changed? && (t.updated_at < Time.current - 1.week)}
end

# then when
iv = ItemVariant.new
iv.save! # no version
iv.updated_at = 2.weeks.ago; iv.save!
iv.first_name = 'this should trigger versioning'
iv.save! # => should create version

Starting with version 4.0.0, new version is never created because attribute 'updated_at' in the if proc is already updated to now. Works fine under 3.0.8.

I'm not familiar enough with the codebase but it might be related to this pull request: #563

[jaredbeck]

This was a deliberate change in 4.0.0, specifically #375.

You can change your proc as follows:

- if: proc {|t| t.changed? && (t.updated_at < Time.current - 1.week)}
+ if: proc {|t| t.changed? && (t.updated_at_was < Time.current - 1.week)}

This breaking change in 4.0.0 is documented in https://github.com/airblade/paper_trail/blob/master/CHANGELOG.md as follows:

#375 / #374 / #354 / #131 - Versions are now saved with an after_ callback, instead of a before_ callback. This ensures that the timestamp field for a version matches the corresponding timestamp in the model.

Thanks for opening the issue, I can see why you'd think it was a regression, but it was deliberate.

[gamov]

oic, thanks @jaredbeck! It makes sense now. I find it a bit counter-intuitive though, maybe it would be good to mention it in the doc, especially under 'Choosing When To Save New Versions'.

[jaredbeck]

.. maybe it would be good to mention it in the doc, especially under 'Choosing When To Save New Versions'.

That would be helpful, thanks. Please submit a PR.