clear rolled back versions from associated model

[moserrya]

I propose this change to fix an issue where, under the right circumstances, version records are created for changes that never took place. Let's say I have two models, Item and Location, and attempt to save changes in a transaction:

item.transaction do
  item.update_attributes!(sku: 'AYH123HJLF')
  Location.first.update_attributes!(code: '999-999')
end

The Item model here has_paper_trail. A version is created for the item's update_attributes! call is created and then rolled back, as expected. However, if we rescue from the error that happens when we run Location.first.update_attributes! and then call item.save, the rolled back version created when we tried to update the sku in a transaction is also saved - even though the sku on the item is not changed.

An alternative approach - could try setting autosave: false in has_paper_trail

[batter]

I think this makes sense.. I'm guessing the concern here is a failure on the first update, then a second update going through and a version being persisted for a state change that never happened? Any chance you can add some tests?

[moserrya]

This is exactly the concern. I will add tests.

[batter]

Cheers