one_to_many.rb in rom-sql-0.9.0

- old
+ new
@@ -1,9 +1,52 @@
 module ROM
   module SQL
     class Association
-      class OneToMany < OneToOne
+      class OneToMany < Association
         result :many
+
+        # @api public
+        def call(relations)
+          with_keys(relations) do |left_pk, right_fk|
+            right = relations[target.relation]
+            columns = right.header.qualified.to_a
+
+            relation = right
+              .inner_join(source, left_pk => right_fk)
+              .select(*columns)
+              .order(*right.header.project(*right.primary_key).qualified)
+
+            relation.with(attributes: relation.header.names)
+          end
+        end
+
+        # @api public
+        def combine_keys(relations)
+          Hash[*with_keys(relations)]
+        end
+
+        # @api public
+        def join_keys(relations)
+          with_keys(relations) { |source_key, target_key|
+            { qualify(source, source_key) => qualify(target, target_key) }
+          }
+        end
+
+        # @api private
+        def associate(relations, child, parent)
+          pk, fk = join_key_map(relations)
+          child.merge(fk => parent.fetch(pk))
+        end
+
+        protected
+
+        # @api private
+        def with_keys(relations, &block)
+          source_key = relations[source.relation].primary_key
+          target_key = relations[target.relation].foreign_key(source.relation)
+          return [source_key, target_key] unless block
+          yield(source_key, target_key)
+        end
       end
     end
   end
 end