Dirty (changed) attributes: since when are the values in the changeset strings (instead of objects)?

Question

I'm using optimistic locking to prevent people overwriting each others changes in race conditions.

Since I upgraded Rails from 5.1 to 5.2, my specs break, and I tracked it down to the fact that in the changes array, the changes that are related to a file upload are not any longer Uploader elements, but bare strings.

Before:

[1] pry(#<User>)> change
=> [
    [0] #<AvatarUploader:0x007fcc7117bc00 # Value before
    [1] #<AvatarUploader:17bc0cc7100x997f # Current value

Now:

[1] pry(#<User>)> change
=> [
    [0] "image.jpg", # Value before
    [1] "avatar.png" # Current value
]

How can I fix this?

Answer 1

I didn't find out why the afore-mentioned behaviour changed, but I could fix it.

Code before:

@user.changes.map do |attribute, change|
  unless ['updated_at', 'lock_version'].include? attribute
    StaleInfo.new resource:     resource,
                  attribute:    attribute,
                  value_before: change[0],
                  value_after:  change[1]
  end
end

Code now:

@user.changes.map do |attribute, change|
  unless ['updated_at', 'lock_version'].include? attribute
    StaleInfo.new resource:     resource,
                  attribute:    attribute,
                  value_before: resource.class.find(resource.id).send(attribute),
                  value_after:  resource.send(attribute)
  end
end

It feels quite quirky this way though, and it needs an additional DB query (to load the original object).