Node translation doesn't prevent duplicates

We also need a check for this at submit time.

Good point.

I guess this would be a translation_nodeapi_validate() function:

* Test for node type is translatable

* Determine the applicable tnid by checking node->tnid or node->translation_source->tnid

* get translations (translation_node_get_translations($tnid), set form error on 'language' field if the language value is already in the translations array.

@nedjo: sounds good.

I added translation_nodeapi_validate() but then discovered that hook_nodeapi_prepare() actually fires even when using the back button, and since it was wiping out the node->language etc. before we got to submit, we end up with the same drupal_set_message() and no duplicate on submit anyway.

So, this patch keeps the _prepare(), doesn't add a validate, and adds tests for both visiting the node/add page again manually, and also a resubmission of the same form (which is equivalent to using the back button).

In both cases, you can create the node you're posting, but it'll simply not have a tnid - it'll be new content in it's own right. I'm not convinced this is ideal from a usability standpoint (although you're already at this page incorrectly anyway if you get there) - but it does fix the bug.

This could probably do with some manual testing by someone to confirm the same behaviour I'm getting - i.e. that we really don't need a _nodeapi_validate(). I think if we were to remove the early return; in _prepare() then we'd actually need the _validate() as well, which'd allow for form_set_error() to prevent posting at all - but that's adding extra code to do much the same thing, so if it's not needed, I don't think we should go out of our way to add it in.

Discussed this with nedjo in irc, and there's situtations where you might get the _validate() being called in contrib even if it doesn't happen in core. So I've added that back in.

I tested this and it all works great, including tests.

Cheers,
Stella

A quick summary of the issue:

Issue:

• You can create multiple translations of a node, in the same language, by visiting the 'add translation' url directly, e.g. node/add/page?translation=1&language=fr

Patch:

• Ensures a translation for that node and language doesn't already exist before displaying the 'add node' form, and before it is saved to the database.
• An error message is displayed if the translation is already present.
• Includes a test which ensures duplicate translations can not be created.

Cheers,
Stella

The last submitted patch failed testing.

Patch re-roll

Marking back to RTBC

The last submitted patch failed testing.

Marking for a retest

moving back to RTBC

Oops. Sorry! I thought I had committed this already!

Committed to HEAD. :)

Marking down to 6.x, as I believe this is an issue there as well, yes?