validates_numericality_of works differently in 8.1.1 because of type cast

[artur79]

I'm upgrading Rails app from mongoid 7.5 to 8.1.1. I had validations like:

field :number_per_year, type: Float, default: 0

validates_numericality_of :number_per_year, allow_blank: true

When using 7.5 and I pass e.g. string 'foo' validation does not pass as expected. But in mongoid 8.1.1 as I'v found when passing string and it's not a number it's casted to number, if cast can not be done it's silently converted to nil. So now my validation passes when it should not. I'v refactored it that way:

validates_numericality_of :number_per_year, if: -> { number_per_year_before_type_cast.present? }

It works as expected now but I want to make sure are there any drawbacks/dangers in that approach?

[johnnyshields]

My recommendation as a long time Mongoid user is to stay on Mongoid 7.x.

[artur79]

Of course you can do that as well!

or if I include it in Gemfile like this

gem 'mongoid', '7.5.4', git: 'https://github.com/tablecheck/mongoid-ultra.git', branch: '7.5-stable'

is this the mongoid version 7.5 with minimal changes to make it work with rails 8 ?

[johnnyshields]

I use this commit ref on prod with Rails 8:
tablecheck/mongoid-ultra@4c4593e

[artur79]

I use this commit ref on prod with Rails 8: tablecheck/mongoid-ultra@4c4593e

ok, I think I got it now, like ?

gem 'mongoid',
    github: 'tablecheck/mongoid-ultra',
    branch: '7.5-stable',
    ref: '4c4593e'

[johnnyshields]

Yes, that looks correct.

[artur79]

@johnnyshields I'm not sure is it a change from your fork or from rails 6 to 8 update but before when I was using official mongoid 7.5 with rails 6.1 for a field like

field :hours, type: Float, default: 0

and I'v assigned some random string to hours the value became nil and model was invalid.
And now when I use rails 8 and your fork model is valid and value becomes 0.0 so it's like casted somewhere

I guess I could use similar approach I'v asked about for mongoid 8.5 #6043 but I'm just trying to understand what has changed ? Maybe some validations order has changed ?

[johnnyshields]

By the way, this is an error that I pointed out a long time ago that we need to do a better way of type casting. We cannot simply type cast String "foo" to Integer nil or 0 and allow a silent failure to happen; it needs to either raise an error or fail the validation step.