Importing into node-add-form conflicts with Panels Page Manager node-edit template

Ctools conflict with pubmed/doi import is mentioned in #502562: Failure to handle DOI and BibTex pre-populate action. I just ran into this problem too, and decided to try to track it down. (I'm using biblio-6.x-2.x-dev together with a collection of ctools and panels modules.)

First, a bit of history: Importing using DOI and PubMedID both used to work for me, and they both stopped working at the same time a few months ago.

To track down the problem, first I disabled ctools (which also meant disabling all my panels-related modules) and saw that importing worked again.

So then I re-enabled everything one by one, checking importing along the way. Enabling ctools alone did not break importing, and nor did enabling Panels. It was when I enabled Page Manager that the import from both services returned an empty form.

I also ran grep "want form" on my modules folder and came up with the same as this comment from the above mentioned issue.

modules/ctools/plugins/contexts/node_add_form.inc:      $form_state = array('want form' => TRUE, 'args' => array($node));
modules/ctools/plugins/contexts/node_edit_form.inc:    $form_state = array('want form' => TRUE, 'args' => array($node));

Then I remembered, a few months ago when this stopped working for me (but I didn't have time to look into it) is around the time when I started using the built-in node-edit page in Page Manager (I've got 2 variants both selected by content types that are not biblio).

So, I disabled that page from Page Manager (admin/build/pages), and presto, importing populates the node form again!

So, it sounds like ctools/plugins/contexts/node_add_form.inc is where the conflict is happening. Makes sense.

If you aren't familiar with Panels, here are a few quick steps to reproduce:

1. verify that DOI and PubMed import are working
2. install/enable ctools and panels, and also enable page_manager (in Chaos Tools group)
3. browse to Page Manager (admin/build/pages) and **enable node-edit page**
4. try importing with DOI and PubMed and see the node add form fields empty
5. if it doesn't fail, try adding a variant to your node-edit page (I disabled my variants and it still failed but not sure if it will with no variants)

I don't have time at the moment to drill down any further, but this is a good time to turn it over anyway. I don't have any intuition into whether it's a biblio issue or a page_manager issue, but I thought I'd start here since I don't see any similar issues in either the Panels or the Ctools queues.