spree/spree — pull request #4800 by Senjai (2014-06-06 22:26:45+00:00)
Title: Ensure shipments are also destroyed when the order is emptied.

There is an issue when attempting to clear a cart at later states in the checkout process.

Specifically, taking a cart to the confirm step (or any step where shipments are created) and emptying your cart will make the order unviewable in the admin interface.

This is because the shipments aren't destroyed when the order is reset. Welcome any feedback.