Find versions where a specific thing was changed

changes_to.rb

class ActiveRecord::Associations::CollectionProxy::ActiveRecord_Associations_CollectionProxy_PaperTrail_Version
  def changes_to
    raise ArgumentError, "block required" unless block_given?

    result = []
    changes = scope.to_a.map do |version|
      version_state = yield version.reify
      [version_state, version]
    end.each_cons(2).select do |old, new|
      old.first != new.first
    end

    return [] if changes.empty?

    changes << [changes.last.last, nil]
    changes.map do |(state, version), _|
      [state, {whodunnit: version.whodunnit, when: version.created_at, version_id: version.id}]
    end
  end
end