StepValueValidator does not take into account min_value

[James Meakin]

If you define a number input with <input type="number" min=1 step=2>, client side this will only allow positive odd numbers.

We could generate the same input in a Django form with IntegerField(min_value=1, step_size=2) and Field.localize is False, which would then use MinValueValidator and StepValueValidator.

We then get into a problem as StepValueValidator always uses 0 as the base, so step_size=2 only even numbers are allowed. This then conflicts with the client side validation, and the user cannot submit any value for the input.

I'm unsure if this is a bug or whether this is just a configuration problem, apologies if so, but the behaviour does seem to me to conflict with how min and step is handled by browsers.

[Mariusz Felisiak]

Thanks for the report! As far as I'm aware we should pass min_value to the StepValueValidator. Bug in 3a82b5f655446f0ca89e3b6a92b100aa458f348f.

[Kapil Bansal]

Thanks for the report. I think this is a bug. We need to consider min value also with step_size

[Jacob Rief]

There is a patch: ​https://github.com/django/django/pull/16742

will be fixed in Django-5.0

[Jacob Rief]

pull request has been fixed for dev branch

[Natalia Bidart]

Hello Jacob,

When the PR for this ticket is updated to the latest requests from reviewers, ideally you should unset the ticket's flags "needs documentation" and "patch needs improvement". That way, the PR will re-appear in the list of branches needing re-review. I have unset these for you now.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 1fe0b16:

Fixed #34473 -- Fixed step validation for form fields with non-zero minimum value.