Make stock location association optional

Prepare for removal

app/models/spree/inventory_unit.rb

@@ -57,8 +57,7 @@ module Spree
     end
 
     def find_stock_item
-      Spree::StockItem.find_by(stock_location_id: shipment.stock_location_id,
-                               variant_id:)
+      Spree::StockItem.find_by(variant_id:)
     end
 
     private

app/models/spree/order_inventory.rb

@@ -67,8 +67,7 @@ module Spree
       end
 
       target_shipment || order.shipments.detect do |shipment|
-        (shipment.ready? || shipment.pending?) &&
-          variant.stock_location_ids.include?(shipment.stock_location_id)
+        shipment.ready? || shipment.pending?
       end
     end
 

app/models/spree/shipment.rb

@@ -8,7 +8,9 @@ module Spree
 
     belongs_to :order, class_name: 'Spree::Order'
     belongs_to :address, class_name: 'Spree::Address'
-    belongs_to :stock_location, class_name: 'Spree::StockLocation'
+
+    # WIP: phasing out stock location, it's not used.
+    belongs_to :stock_location, class_name: 'Spree::StockLocation', optional: true
 
     has_many :shipping_rates, dependent: :delete_all
     has_many :shipping_methods, through: :shipping_rates
@@ -257,7 +259,7 @@ module Spree
     end
 
     def to_package
-      package = OrderManagement::Stock::Package.new(stock_location, order)
+      package = OrderManagement::Stock::Package.new(order)
       grouped_inventory_units = inventory_units.includes(:variant).group_by do |iu|
         [iu.variant, iu.state_name]
       end
@@ -301,6 +303,11 @@ module Spree
       !shipped? && !order.canceled?
     end
 
+    # We still use the `unstock` and `restock` methods of the stock location.
+    def stock_location
+      @stock_location ||= DefaultStockLocation.find_or_create
+    end
+
     private
 
     def line_items

app/models/spree/stock_item.rb

@@ -4,7 +4,9 @@ module Spree
   class StockItem < ApplicationRecord
     acts_as_paranoid
 
-    belongs_to :stock_location, class_name: 'Spree::StockLocation', inverse_of: :stock_items
+    # WIP: phasing out stock location, it's not used.
+    belongs_to :stock_location, class_name: 'Spree::StockLocation', inverse_of: :stock_items,
+                                optional: true
     belongs_to :variant, -> { with_deleted }, class_name: 'Spree::Variant'
     has_many :stock_movements, dependent: :destroy
 
@@ -40,6 +42,12 @@ module Spree
       self[:count_on_hand] = value
     end
 
+    # Other code still calls this.
+    # TODO: remove usage
+    def stock_location
+      @stock_location ||= DefaultStockLocation.find_or_create
+    end
+
     private
 
     def process_backorders

app/models/spree/stock_location.rb

@@ -13,11 +13,19 @@ module Spree
 
     validates :name, presence: true
 
-    after_create :create_stock_items
-
     # Wrapper for creating a new stock item respecting the backorderable config
     def stock_item(variant)
-      stock_items.where(variant_id: variant).order(:id).first
+      StockItem.where(variant_id: variant).order(:id).first
+    end
+
+    # We have only one default stock location and it may be unpersisted.
+    # So all stock items belong to any unpersisted stock location.
+    def stock_items
+      StockItem.all
+    end
+
+    def stock_movements
+      StockMovement.all
     end
 
     def stock_item_or_create(variant)
@@ -47,11 +55,5 @@ module Spree
     def fill_status(variant, quantity)
       variant.fill_status(quantity)
     end
-
-    private
-
-    def create_stock_items
-      Variant.find_each { |variant| stock_items.create!(variant:) }
-    end
   end
 end

app/models/spree/variant.rb

@@ -268,9 +268,7 @@ module Spree
     def create_stock_items
       return unless stock_items.empty?
 
-      StockLocation.find_each do |stock_location|
-        stock_items.create!(stock_location:)
-      end
+      stock_items.create!
     end
 
     def update_weight_from_unit_value

db/migrate/20250108234658_allow_null_stock_location_id_on_spree_stock_items.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AllowNullStockLocationIdOnSpreeStockItems < ActiveRecord::Migration[7.0]
+  def change
+    change_column_null :spree_stock_items, :stock_location_id, true
+  end
+end

db/schema.rb

@@ -822,7 +822,7 @@ ActiveRecord::Schema[7.0].define(version: 2025_01_13_055412) do
   end
 
   create_table "spree_stock_items", id: :serial, force: :cascade do |t|
-    t.integer "stock_location_id", null: false
+    t.integer "stock_location_id"
     t.integer "variant_id", null: false
     t.integer "count_on_hand", default: 0, null: false
     t.datetime "created_at", precision: nil, null: false

engines/order_management/app/services/order_management/stock/package.rb

@@ -5,11 +5,10 @@ module OrderManagement
     class Package
       ContentItem = Struct.new(:variant, :quantity, :state)
 
-      attr_reader :stock_location, :order, :contents
+      attr_reader :order, :contents
       attr_accessor :shipping_rates
 
-      def initialize(stock_location, order, contents = [])
-        @stock_location = stock_location
+      def initialize(order, contents = [])
         @order = order
         @contents = contents
         @shipping_rates = []
@@ -94,7 +93,6 @@ module OrderManagement
       def to_shipment
         shipment = Spree::Shipment.new
         shipment.order = order
-        shipment.stock_location = stock_location
         shipment.shipping_rates = shipping_rates
 
         contents.each do |item|

engines/order_management/app/services/order_management/stock/packer.rb

@@ -11,7 +11,7 @@ module OrderManagement
       end
 
       def package
-        package = OrderManagement::Stock::Package.new(stock_location, order)
+        package = OrderManagement::Stock::Package.new(order)
         order.line_items.each do |line_item|
           next unless stock_location.stock_item(line_item.variant)
 

engines/order_management/spec/services/order_management/stock/package_spec.rb

@@ -7,11 +7,10 @@ module OrderManagement
     RSpec.describe Package do
       context "base tests" do
         let(:variant) { build(:variant, weight: 25.0) }
-        let(:stock_location) { build(:stock_location) }
         let(:distributor) { create(:enterprise) }
         let(:order) { build(:order, distributor:) }
 
-        subject { Package.new(stock_location, order) }
+        subject { Package.new(order) }
 
         it 'calculates the weight of all the contents' do
           subject.add variant, 4
@@ -80,7 +79,7 @@ module OrderManagement
                       Package::ContentItem.new(variant2, 1),
                       Package::ContentItem.new(variant3, 1)]
 
-          package = Package.new(stock_location, order, contents)
+          package = Package.new(order, contents)
           expect(package.shipping_methods.size).to eq 2
         end
 
@@ -96,7 +95,6 @@ module OrderManagement
 
           shipment = subject.to_shipment
           expect(shipment.order).to eq subject.order
-          expect(shipment.stock_location).to eq subject.stock_location
           expect(shipment.inventory_units.size).to eq 3
 
           first_unit = shipment.inventory_units.first
@@ -122,9 +120,7 @@ module OrderManagement
       end
 
       context "#shipping_methods and #shipping_categories" do
-        let(:stock_location) { double(:stock_location) }
-
-        subject(:package) { Package.new(stock_location, order, contents) }
+        subject(:package) { Package.new(order, contents) }
 
         let(:enterprise) { create(:enterprise) }
         let(:other_enterprise) { create(:enterprise) }

engines/order_management/spec/services/order_management/stock/prioritizer_spec.rb

@@ -6,12 +6,11 @@ module OrderManagement
   module Stock
     RSpec.describe Prioritizer do
       let(:order) { create(:order_with_line_items, line_items_count: 2) }
-      let(:stock_location) { build(:stock_location) }
       let(:variant1) { order.line_items[0].variant }
       let(:variant2) { order.line_items[1].variant }
 
       def pack
-        package = Package.new(order, stock_location)
+        package = Package.new(order)
         yield(package) if block_given?
         package
       end

spec/factories/stock_factory.rb

@@ -8,7 +8,7 @@ FactoryBot.define do
       contents { [] }
     end
 
-    initialize_with { new(stock_location, order, contents) }
+    initialize_with { new(order, contents) }
 
     factory :stock_package_fulfilled do
       after(:build) do |package, evaluator|

spec/factories/stock_location_factory.rb

@@ -17,15 +17,15 @@ FactoryBot.define do
     end
 
     factory :stock_location_with_items do
-      after(:create) do |stock_location, _evaluator|
+      after(:create) do |_stock_location, _evaluator|
         # variant will add itself to all stock_locations in an after_create
         # creating a product will automatically create a master variant
         product_1 = create(:product)
         product_2 = create(:product)
 
-        stock_location.stock_items.where(variant_id: product_1.variants.first.id)
+        Spree::StockItem.where(variant_id: product_1.variants.first.id)
           .first.adjust_count_on_hand(10)
-        stock_location.stock_items.where(variant_id: product_2.variants.first.id)
+        Spree::StockItem.where(variant_id: product_2.variants.first.id)
           .first.adjust_count_on_hand(20)
       end
     end

spec/models/spree/stock_location_spec.rb

@@ -12,21 +12,6 @@ module Spree
       expect(subject.stock_items.count).to eq Variant.count
     end
 
-    context "handling stock items" do
-      let!(:variant) { create(:variant) }
-
-      context "given a variant" do
-        context "propagate all variants" do
-          subject { StockLocation.new(name: "testing") }
-
-          specify do
-            expect(subject.stock_items).to receive(:create!).at_least(:once)
-            subject.save!
-          end
-        end
-      end
-    end
-
     it 'finds a stock_item for a variant' do
       stock_item = subject.stock_item(variant)
       expect(stock_item.count_on_hand).to eq 15