If you delete a title which is on someone's list, that list can no longer be accessed because of an error:

Can't call method "field" on an undefined value at C4/Koha.pm line 1217.

The line in question is part of GetNormalizedUPC:

        @fields = $record->field('024');

Called by VirtualShelves/Page.pm:


       $this_item->{'normalized_upc'}  = GetNormalizedUPC($record,$marcflavour);

Seems like there's several things that can be done here:

1. Remove titles from lists when they are deleted. The disadvantage here is that someone might have been using a list as a bibliography, for instance, and losing the title makes their information incomplete. To follow up:

2. Add error handling to VirtualShelves/Page.pm. Don't try to pull the full MARC data for a biblionumber which doesn't exist. Some choices for the display:

  a. Pretend nothing happened, title never existed
  b. Indicate that a title was removed, no information available.
  c. Indicate that a title was removed, pull basic info from deletedbiblio.

3. Add error handling to Koha.pm. Don't die if an empty record gets passed. This seems like a no-brainer.