Merge pull request #4146 from jarednorman/why-would-you-ever-want-the…

…-same-option-value-on-a-variant-twice

Make option value to variant association unique

core/db/migrate/20210815004823_add_unique_index_to_option_values_variants.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+class AddUniqueIndexToOptionValuesVariants < ActiveRecord::Migration[5.2]
+  def up
+    remove_index :spree_option_values_variants, [:variant_id, :option_value_id]
+    add_index :spree_option_values_variants, [:variant_id, :option_value_id],
+              name: "index_option_values_variants_on_variant_id_and_option_value_id",
+              unique: true
+  end
+
+  def down
+    remove_index :spree_option_values_variants, [:variant_id, :option_value_id]
+    add_index :spree_option_values_variants, [:variant_id, :option_value_id],
+              name: "index_option_values_variants_on_variant_id_and_option_value_id"
+  end
+end

core/spec/models/spree/variant_spec.rb

@@ -1042,4 +1042,9 @@
     subject { variant.sku_and_options_text }
     it { is_expected.to eq("EB1 Size: S") }
   end
+
+  it "cannot have the same option value multiple times" do
+    expect { variant.option_values << variant.option_values.first }
+      .to raise_error ActiveRecord::RecordNotUnique
+  end
 end