Allow to specify a type for foreign key column in migrations

[Andrey Novikov & Łukasz Sarnacki]

activerecord/CHANGELOG.md

@@ -1,3 +1,14 @@
+*   Allow to specify a type for created foreign key column in `references` and
+    `add_reference` in migrations.
+
+    Example:
+
+        change_table :vehicle do |t|
+          t.references :station, type: :uuid
+        end
+
+    *Andrey Novikov & Łukasz Sarnacki*
+
 *   `create_join_table` removes a common prefix when generating the join table.
     This matches the existing behavior of HABTM associations.
 

activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb

@@ -280,12 +280,19 @@ module ActiveRecord
         column(:updated_at, :datetime, options)
       end
 
+      # Adds an appropriately-named _id column as <tt>:integer</tt> (or whatever <tt>:type</tt> option specifies),
+      # plus a corresponding _type column if the <tt>:polymorphic</tt> option is supplied. If <tt>:polymorphic</tt>
+      # is a hash of options, these will be used when creating the <tt>_type</tt> column. The <tt>:index</tt> option
+      # will also create an index, similar to calling <tt>add_index</tt>.
+      #
+      #   references :tagger, polymorphic: true, index: true, type: :uuid
       def references(*args)
         options = args.extract_options!
         polymorphic = options.delete(:polymorphic)
         index_options = options.delete(:index)
+        type = options.delete(:type) || :integer
         args.each do |col|
-          column("#{col}_id", :integer, options)
+          column("#{col}_id", type, options)
           column("#{col}_type", :string, polymorphic.is_a?(Hash) ? polymorphic : options) if polymorphic
           index(polymorphic ? %w(id type).map { |t| "#{col}_#{t}" } : "#{col}_id", index_options.is_a?(Hash) ? index_options : {}) if index_options
         end

activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb

@@ -619,7 +619,8 @@ module ActiveRecord
       def add_reference(table_name, ref_name, options = {})
         polymorphic = options.delete(:polymorphic)
         index_options = options.delete(:index)
-        add_column(table_name, "#{ref_name}_id", :integer, options)
+        type = options.delete(:type) || :integer
+        add_column(table_name, "#{ref_name}_id", type, options)
         add_column(table_name, "#{ref_name}_type", :string, polymorphic.is_a?(Hash) ? polymorphic : options) if polymorphic
         add_index(table_name, polymorphic ? %w[id type].map{ |t| "#{ref_name}_#{t}" } : "#{ref_name}_id", index_options.is_a?(Hash) ? index_options : {}) if index_options
       end

activerecord/test/cases/adapters/postgresql/uuid_test.rb

@@ -233,7 +233,7 @@ class PostgresqlUUIDTestInverseOf < ActiveRecord::TestCase
         t.string 'title'
       end
       connection.create_table('pg_uuid_comments', id: :uuid) do |t|
-        t.uuid :uuid_post_id, default: 'uuid_generate_v4()'
+        t.references :uuid_post, type: :uuid
         t.string 'content'
       end
     end

activerecord/test/cases/migration/change_table_test.rb

@@ -72,6 +72,20 @@ module ActiveRecord
         end
       end
 
+      def test_references_column_type_with_polymorphic_and_type
+        with_change_table do |t|
+          @connection.expect :add_reference, nil, [:delete_me, :taggable, polymorphic: true, type: :string]
+          t.references :taggable, polymorphic: true, type: :string
+        end
+      end
+
+      def test_remove_references_column_type_with_polymorphic_and_type
+        with_change_table do |t|
+          @connection.expect :remove_reference, nil, [:delete_me, :taggable, polymorphic: true, type: :string]
+          t.remove_references :taggable, polymorphic: true, type: :string
+        end
+      end
+
       def test_timestamps_creates_updated_at_and_created_at
         with_change_table do |t|
           @connection.expect :add_timestamps, nil, [:delete_me]

activerecord/test/cases/migration/references_statements_test.rb

@@ -55,6 +55,16 @@ module ActiveRecord
         assert index_exists?(table_name, :tag_id, name: 'index_taggings_on_tag_id')
       end
 
+      def test_creates_reference_id_with_specified_type
+        add_reference table_name, :user, type: :string
+        assert column_exists?(table_name, :user_id, :string)
+      end
+
+      def test_does_not_create_reference_id_with_specified_type
+        add_reference table_name, :user
+        assert_not column_exists?(table_name, :user_id, :string)
+      end
+
       def test_deletes_reference_id_column
         remove_reference table_name, :supplier
         assert_not column_exists?(table_name, :supplier_id, :integer)