url should not be updated if model fails validation?

[zapnap]

Use case: I have a model whose title is used to create the url / permalink. I'm using sync_url => true. update_attributes is called with a title value that fails validation (blank value when presence is required, for example).

When this happens, my Rails application re-renders the template with errors so the user can fix the validation problems. However, the url value has changed. Now, route shortcuts are broken because the model instance has an empty url, when the url probably never should have been updated at all.

I created a failing test to demonstrate the scenario. Can work on a patch if this makes sense (note that an after_validation callback won't fire if validation fails):

zapnap@00ada38

[zapnap]

I added a possible solution for this issue in my branch this morning; will send a pull request. If you have a more elegant way to resolve it please let me know. Thanks!

[rsl]

pulled this into master. i think. lemme know if i screwed it up. didn't close ticket [stupid me].

[zapnap]

Thanks!