PHP Warning with unchecked taxonomy lists

I attempted to recreate the scenario on my system. I'm running the latest cvs build as of Friday March 10, 2006 10:00AM PST, with PHP 4.4.1 and MySQL 5.0.18. I created 2 vocabularies with multiple terms and then created a page, selecting a term from one category but not the other. The page was created without any issues.

There are 2 issues here:

a) Primary issue: Taxonomy forms (or I believe any select form) with the multiple select option cannot have all their elements deselected, once they have already been set a value. i.e. select elements which have their existing selections deselected will revert to their default values. I believe the same issue cropped up with checkboxes as well, and should be related to the following block of code:

    $posted = (isset($_POST['edit']) && ($_POST['edit']['form_id'] == $form_id));
    $edit = $posted ? $_POST['edit'] : array();
    $ref =& $form_values;

    foreach ($form['#parents'] as $parent) {
      $edit = isset($edit[$parent]) ? $edit[$parent] : NULL;
      $ref =& $ref[$parent];
    }

    $form['#ref'] = &$ref;
    if (!isset($form['#value'])) {
      if ($posted) {
        if (isset($edit)) {
          $form['#value'] = $edit; // normal element
          $form['#needs_validation'] = TRUE;
        }
        elseif (isset($form['#return_value'])) {
          $form['#value'] = '0'; // checkbox unchecked
          $form['#needs_validation'] = TRUE;
        }
      }
      if (!isset($form['#value'])) {
        $function = $form['#type'] . '_value';
        if (function_exists($function)) {
          $function($form);
        }
        else {
          $form['#value'] = $form['#default_value'];
        }
      }
    }

b) Immediate issue: Taxonomy forms for each vocabulary are set default values which also include terms from other vocabularies. So, due to the issue in a) when existing values for a vocabulary are deselected (i.e. there are no selections), the vocabulary reverts to its default values. These include values from other vocabularies as well and therefore trigger "duplicate" errors as the same term is saved twice (or more times). Patch attached. I've also added some minor formatting for some illegible (related) code.

-K

looks good, can somebody test it?

i am still seeing the bug. i cannot clear the selections on a multiple select vocab

@Moshe: Yes, the patch only addresses the database error. The "clearing" issue needs to be fixed in form.inc. and is very likely applicable to all multi-select elements i.e. the attached patch only addresses part b.

-K

works for me

I've created a separate issue for the forms bug.

Thanks for the reviews Moshe, timcn.
-K

Committed to HEAD. Great job guys! :)

Zen told me that we don't need the code that timcn added. I propose to remove it.

Yep, selecting "none" by default etc. is unnecessary - it is there more to allow a user to "not select anything" than to tell the user that nothing has been selected. i.e. some end users might not be aware of "Ctrl + click" as an option to unselect an item.

I hadn't noticed that a different patch had gone through earlier - sorry about that.

Cheers,
-K

RTC-ing. Patch still applies albeit with an offset.

-K

applied