I think more like this

```
def test_hstore_migration
        hstore_migration = Class.new(ActiveRecord::Migration) {
            def change
             change_table("hstores") do |t|
               t.hstore :keys
            end
          end
        }.new

      #hstore_migration = HstoreMigration.new
      hstore_migration.suppress_messages do
        hstore_migration.migrate(:up)
        assert @connection.columns(:hstores).map(&:name).include? "keys"
        hstore_migration.migrate(:down)
        assert_not @connection.columns(:hstores).map(&:name).include? "keys"
      end
    end
```