rails using dirty method for tracing purposes using mobility gem

Question

A rails controller method is attempting to pass object changes

      if @union.update(union_params)
puts '||'
puts @union.changed
puts @union.changes
        @union.update_with_log(union_params, current_user.id)

However, when this runs the console registers an empty hash for the changes and does not even handle the changed verb.

||
{}

The changes verb acts as expectedwhen testing in the console with a variable invoked. However, the application's operating context is with tranlsatable variables with handling through the mobility gem.

In practice the console registers edits the following manner:

Mobility::Backends::ActiveRecord::KeyValue::TextTranslation Update (0.4ms)  UPDATE "mobility_text_translations" SET "value" = $1, "updated_at" = $2 WHERE "mobility_text_translations"."id" = $3 [...]

Why is this behaviour different with mobility & an instance variable?

Answer 1

The method that needs to be invoked is previous_changes as indicated in the documentation towards the end of the Dirty tracking section and not changes (the documentation is not explicit on the latter point at time of writing).