Fix function qualification methods

lib/rom/sql/function.rb

@@ -73,18 +73,23 @@ def name
       #
       # @api private
       def qualified(table_alias = nil)
-        meta(
-          func: ::Sequel::SQL::Function.new(func.name, *func.args.map { |arg| arg.respond_to?(:qualified) ? arg.qualified(table_alias) : arg })
-        )
+        new { |arg|
+          arg.respond_to?(:qualified) ? arg.qualified(table_alias) : arg
+        }
       end
 
       # @see Attribute#qualified_projection
       #
       # @api private
       def qualified_projection(table_alias = nil)
-        meta(
-          func: ::Sequel::SQL::Function.new(func.name, *func.args.map { |arg| arg.respond_to?(:qualified_projection) ? arg.qualified_projection(table_alias) : arg })
-        )
+        new { |arg|
+          arg.respond_to?(:qualified_projection) ? arg.qualified_projection(table_alias) : arg
+        }
+      end
+
+      # @api private
+      def new(&block)
+        meta(func: ::Sequel::SQL::Function.new!(func.name, func.args.map(&block), func.opts))
       end
 
       # @see Attribute#qualified?

spec/unit/function_spec.rb

@@ -91,6 +91,11 @@
         to eql('ROW_NUMBER() OVER (PARTITION BY "name")')
     end
 
+    example 'with the PARTITION BY clause which is aliased' do
+      expect(func.row_number.over(partition: :name, order: :name).as(:row_numbers).sql_literal(ds)).
+        to eql('ROW_NUMBER() OVER (PARTITION BY "name" ORDER BY "name") AS "row_numbers"')
+    end
+
     example 'with the frame clause' do
       expect(func.row_number.over(frame: :all).sql_literal(ds)).
         to eql('ROW_NUMBER() OVER (ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)')

spec/unit/relation/select_append_spec.rb

@@ -17,5 +17,21 @@
       expect(selected.schema.map(&:name)).to eql(%i[id title])
       expect(selected.first).to eql(id: 1, title: "JOE'S TASK")
     end
+
+    context 'functions' do
+      with_adapters(:postgres) do
+        example 'row_number' do
+          selected = relation.select(:id).select_append {
+            [integer::row_number().over(partition: title).as(:row_numbers)]
+          }
+
+          expect(selected.dataset.sql).to eql(<<~SQL.strip.gsub("\n", " "))
+            SELECT "tasks"."id", ROW_NUMBER() OVER (PARTITION BY "tasks"."title") AS "row_numbers"
+            FROM "tasks"
+            ORDER BY "tasks"."id"
+          SQL
+        end
+      end
+    end
   end
 end