Enforce creating option values with an option type

Add a NOT NULL validation at the database level on top
of removing the existing deprecation warning.

Ref #4385.

core/app/models/spree/option_value.rb

@@ -2,9 +2,7 @@
 
 module Spree
  class OptionValue < Spree::Base
- # TODO: Remove optional on Solidus v4.0. Don't forget adding a migration to
- # enforce at the database layer
- belongs_to :option_type, class_name: 'Spree::OptionType', inverse_of: :option_values, optional: true
+ belongs_to :option_type, class_name: 'Spree::OptionType', inverse_of: :option_values
  acts_as_list scope: :option_type
 
  has_many :option_values_variants, dependent: :destroy
@@ -15,15 +13,8 @@ class OptionValue < Spree::Base
 
  after_save :touch, if: :saved_changes?
  after_touch :touch_all_variants
- after_save do
- Spree::Deprecation.warn <<~MSG if option_type.nil?
- Having an option_value with no associated option_type will be deprecated
- on Solidus v4.0
- MSG
- end
 
- # TODO: Remove allow_nil once option_type is required on Solidus v4.0
- delegate :name, :presentation, to: :option_type, prefix: :option_type, allow_nil: true
+ delegate :name, :presentation, to: :option_type, prefix: :option_type
 
  self.allowed_ransackable_attributes = %w[name presentation]
 

core/db/migrate/20230321161854_change_column_null_option_values_option_type_id.rb

@@ -0,0 +1,5 @@
+class ChangeColumnNullOptionValuesOptionTypeId < ActiveRecord::Migration[5.2]
+ def change
+ change_column_null(:spree_option_values, :option_type_id, false)
+ end
+end

core/spec/models/spree/option_value_spec.rb

@@ -50,9 +50,9 @@
  end
  end
 
- it 'deprecates creating an option_value with no associated option_type' do
- expect(Spree::Deprecation).to receive(:warn).with(/deprecated/)
-
- create(:option_value, option_type: nil)
+ it 'raises when creating an option_value with no associated option_type' do
+ expect {
+ create(:option_value, option_type: nil)
+ }.to raise_error(ActiveRecord::RecordInvalid)
  end
 end