Fixed #30115 -- Fixed for sqlite3 get_field_type unhashable type error

[cansarigol]

https://code.djangoproject.com/ticket/30115

[carltongibson]

Someone is going to have to explain this to me... 😊

The error triggered is:

 File ".../django/db/backends/sqlite3/introspection.py", line 65, in get_field_type
    if description.pk and field_type in {'BigIntegerField', 'IntegerField'}:
TypeError: unhashable type: 'dict'

So "change to a tuple", fair enough, but {'BigIntegerField', 'IntegerField'} is a set... So what's going on?

[felixxm]

It looks that field_type is a dict 🤔

[carltongibson]

Right, yes. I was just getting towards thinking that, but still...? 🙂 (We need a test case here showing what's going on.)

(Also these MySQL/MariaDB errors are the same as in #10861 — so something is amiss.)

[felixxm]

MySQL errors are probably related with new version of mysqlclient. Released 3 hours ago.

[felixxm]

I can dig into them later today.

[carltongibson]

Super. Thanks @felixxm!

[charettes]

IMO the real issue here is field_type being a dict. That's unexpected and likely to cause breakages somewhere else. This adjustment only happens to circumvent it.

[cansarigol]

Is this test approach make sense? added test for dict column (charfield) and changed City table pk column type.

[carltongibson]

IMO the real issue here is field_type being a dict.

Yes. Surely that's an error.

[ngnpope]

Superseded by #10871. See my comment on the ticket for an explanation of the problem.