STI type column validation

[ngouy]

Description

When creating STI ish objects, factory bot isn't checking for the type. It doesn't raise any error if the given type doesn't exists in STI subclasses

Reproduction Steps

I have an STI pattern

# models
class ParentClass < ApplicationRecord; end

class Foo < ParentClass; end
class Bar < ParentClass; end

Thus I only have one table in db with the type colomn

Here is my factory

FactoryBot.define do
  factory :parent_class do
    type { ["Foo", "Bar"].sample }

    factory :foo, parent: :parent_class, class: "Foo"
    factory :bar, parent: :parent_class, class: "Bar"
  end
end

Now lets test some things :

ParentClass.new      # <Foo id: nil, type: nil>
Foo.new              # <Foo id: nil, type: "Foo">
build(:parent_class) # <ParentClass id: nil, type: "Bar"> // could be "Foo" also
build(:foo)          # <Foo id: nil, type: "Foo">

So far so good. But here is the bug :

ParentClass.create!(type: "UnknownSubClass") # Raises error
# ActiveRecord::SubclassNotFound Exception: The single-table inheritance mechanism failed to locate the subclass: 'UnknownSubClass'
create(:parent_class, type: "UnknownSubClass") # <ParentClass id: 1, type: "UnknownSubClass">

There is an inconsistency between the real activerecord interface and what factorybot is returning us

Expected behavior

We should get an error

Actual behavior

Everything goes smoothly 😱

System configuration

factory_bot version: 5.1.1 (updated to 6.1.0, same issue) rails version: 6.1.1 ruby version: 2.7.2

[aledustet]

Hello, @ngouy we have tried reproducing this scenario with the reproduction script and substituted the create! call with the process that factory_bot is using internally:

# under the hood create does something similar to this
new_class = ParentClass.new
new_class.type = "UnknownSubClass"
new_class.save!

Full reproduction script

``` ruby require "bundler/inline" gemfile(true) do source "https://rubygems.org" git_source(:github) { |repo| "https://github.com/#{repo}.git" } gem "factory_bot", "~> 5.0" gem "activerecord" gem "sqlite3" end require "active_record" require "factory_bot" require "minitest/autorun" require "logger" ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:") ActiveRecord::Base.logger = Logger.new(STDOUT) ActiveRecord::Schema.define do create_table :parent_classes, force: true do |t| t.string :type end end class ParentClass < ActiveRecord::Base; end class Foo < ParentClass; end class Bar < ParentClass; end FactoryBot.define do factory :parent_class do type { ["Foo", "Bar"].sample } factory :foo, parent: :parent_class, class: "Foo" factory :bar, parent: :parent_class, class: "Bar" end end # ParentClass.create(type: "UnknownSubClass") new_class = ParentClass.new new_class.type = "UnknownSubClass" new_class.save! FactoryBot.create(:parent_class, type: "UnknownSubClass") ```

The behavior is the same as you correctly described. But since this is reproducible without any factory_bot code we are going to close it. Thank you for bringing it up!