float("inf") as an argument to a validator breaks migrations

[w0rp]

Deconstructing float("inf") in validator arguments breaks migrations, probably because repr(float("inf")) == "inf". A similar issue will exist for float("nan").

To reproduce this, you'll need a validator using deconstructible.

from django.utils.deconstruct import deconstructible

@deconstructible
class DoNothingValidator (object):
    def __init__(self, foo):
        self.foo = foo

    def __call__(self, value):
        pass

    def __eq__(self, other):
        return type(self) == type(other) \
        and self.foo == other.foo

Now you'll need to pass the validator with float("inf") to a field.

class SomeModel (Model):
    some_field = IntegerField(
        validators= [DoNothingValidator(float("inf"))],
    )

Now if you run 'makemigrations', you will get output like the following.

...
('some_field', models.IntegerField(validators=[some.path.DoNothingValidator(inf)])),
...

The inf above will cause a NameError when you attempt to migrate, or when you create further migrations with 'makemigrations' again.

[Baptiste Mispelon]

Hi,

I can indeed reproduce this.
I'm going to bump the severity of the ticket too.

Thanks for the detailed bug report!

[Markus Holtermann]

I added a pull request at ​https://github.com/django/django/pull/3476

[Baptiste Mispelon]

Patch looks good (I just have a minor complaint about the alphabetical ordering of imports but that's just cosmetic).

Let's see what the CI has to say.

Thanks!

[Baptiste Mispelon <bmispelon@…>]

In c7c098cf97fbb1416f302c76799058ad63a5f7aa:

Fixed #23770 -- Changed serialization strategy for floats with respect to NaN and Inf

Thanks to w0rp for the report

[Baptiste Mispelon <bmispelon@…>]

In 1f50ea730e250acdc9f62f1ce1a769296fc20bb8:

[1.7.x] Fixed #23770 -- Changed serialization strategy for floats with respect to NaN and Inf

Thanks to w0rp for the report

Backport of c7c098cf97fbb1416f302c76799058ad63a5f7aa from master.