Hide field when output is empty (and DB is not used for storage)

There is a semi-solution for this problem: http://drupal.org/node/1349904

But if you don't want to store field values in the DB, your field will be always visible, even if it empty. I am sure it's a bug in the code, but the module is almost not maintained now. :-(

It would seem that this is not a problem for fields stored in the DB because they are tested as empty/non-empty each time the field is saved (via computed_field_field_is_empty()). If nothing is saved, then Drupal knows there is nothing to display.

Fields that don't use the DB for storage don't receive this "is_empty" check. However, I think it would be possible to implement a similar check at display time within computed_field_field_formatter_view(), which is what the attached patch attempts to do.

Perhaps others could test this out.

I will try your patch as soon as return from vacation.

tested #2, works as described
let's get one more review for RTBC

I can confirm that

1. This is still an essential issue
2. The patch works great
3. Is now set RTBC
4. I'd be happy to see this in the next .dev release :)

Thank you very much for the great work!

=D Thanks. Forgot to select. Sorry xD

Thanks! Looks great. I'll happily commit this once the extra whitespace is removed from line 348.

@colan: Please review and set RTBC again if it's ok!

The corresponding issue for values stored in the DB is #1440234: Zeroes in string types are assumed to be empty (DB used for storage). Please review that one if you can as nobody's look at it yet.

@Anybody: No, sorry, I can still see whitespace there with Dreditor.

Looks like this was one of my patches from long ago. Dunno how that whitespace got in there. I double-checked the the patch still applies cleanly, and though it does there is some offset. Because of this I went ahead with a re-roll (that also stripped white space).

Thanks!