#20999: Cannot specify form_class that isn't subclass of TypedChoiceField for field with choices ---------------------------------------+------------------------ Reporter: carljm | Owner: nobody Type: New feature | Status: new Component: Forms | Version: master Severity: Normal | Keywords: Triage Stage: Unreviewed | Has patch: 0 Needs documentation: 0 | Needs tests: 0 Patch needs improvement: 0 | Easy pickings: 0 UI/UX: 0 | ---------------------------------------+------------------------ In `Field.formfield()`, if `self.choices` is set, Django overrides any supplied `form_class` with `TypedChoiceField` unless the given `form_class` is a subclass of `TypedChoiceField`. This is unnecessarily restrictive (as explicit type checks usually are), and is particularly problematic when working with a field that takes multiple values (such as a Postgres array field), where `TypedMultipleChoiceField` would be the appropriate form field class, because `TypedMultipleChoiceField` is not a subclass of `TypedChoiceField`.
Prior to the fix for #18162, Django was even more restrictive; a custom `form_class` was not respected at all when choices were set. I think the wrong fix for #18162 was chosen. The original patch provided by rafallo there would have respected a new keyword argument to `formfield()`, `form_class_for_choices`. This provides full flexibility, and is conceptually more correct; since a totally different form field is generally needed for the same db field when there are choices, a separate keyword argument to control this form field is appropriate. I propose that we switch to rafallo's fix (though I prefer the slightly shorter name `choices_form_class`). Unfortunately since the subclass check was committed and released in the 1.6 betas, we probably still have to maintain compatibility with people passing a subclass of `TypedChoiceField` as `form_class` and expecting it to be used when choices are set. -- Ticket URL: <https://code.djangoproject.com/ticket/20999> Django <https://code.djangoproject.com/> The Web framework for perfectionists with deadlines. -- You received this message because you are subscribed to the Google Groups "Django updates" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-updates+unsubscr...@googlegroups.com. To post to this group, send email to django-updates@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-updates/049.a690a8b11e67c49bd6e67650c2fcf69d%40djangoproject.com. For more options, visit https://groups.google.com/groups/opt_out.