Add gift code box on signup form
if user is already subscribed, send straight to getting started page
More steps and feature tweaks for claiming gift codes
Associate gift codes with subscriptions instead of users
gocardless ID presence is no longer required
A subscription only has one gift code
only cancel gocardless if there is a gocardless ID
test for gift code state after claiming
Swap direction of gift code / subscription relation
Pass gift code through to subscription controller instead of processing during user signup
Create subscriptions for entered gift codes
Add user validator for gift codes
Check for already-used gift codes
Allow gift code to be passed through when signing up
fix another HTML escaping test
Fix subscription code check
Refactor calculation of subscription end date
gocardless ids can now be nil
Generate shipments for gift code subscriptions
Fix failing test