CP collection listing can be broken if a user is deleted

[jackmcdade]

Bug Description

If you have a users field (e.g. author) and add it to your listing column for the collection, the listing will break if you delete a user that has been assigned to an entry.

You'll get a Call to member function id() on null error on the page.

Environment

Statamic version: 3.0.7

PHP version: 7.4

Install method (choose one):

• Fresh install from statamic/statamic

[jetwes]

I have this behaviour on a complete fresh install. No user was deleted. If I click on collections in the cp I get this error.
The front is also broken - same error....

EDIT: Same on blueprints in the cp

PHP: 7.4.9

[duncanmcclean]

What should happen instead if the user doesn't exist, should it just display as nothing? I'm thinking about creating a bug fix for this.

[jackmcdade]

Yes it should just null out the author, and the next time the entry is saved it'll get removed from the data

[jackmcdade]

My guess is the answer lies in here: https://github.com/statamic/cms/blob/master/src/Fieldtypes/Users.php#L68-L77

But i've been wrong many times before 😂

[duncanmcclean]

Sweet, I'll have a look over the weekend 😃

[duncanmcclean]

Fixed in db9968c