Using Rails 4.0:
After rolling back the combine_items_in_cart migration, we expect to be able to view the contents of the cart without the items combined.
I get ActiveRecord::PendingMigrationError instead.
In the changelog for Rails 4.0, we have: “Added ActiveRecord::Migration.check_pending! that raises an error if migrations are pending.”
How can we do what the book does, and roll back a migration and view the app in the pre-migration state? Is this really a new thing for Rails 4.0?