id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
35906	SplitDateTime widget crashes while processing initials	Михаил Акопян		"I have a model with DateTime field. I want to set initials for this field in django admin by using query params. For example:


{{{
# models.py

class MyModel(models.Model):
    created_at = models.DateTimeField()


# admin.py

@admin.register(MyModel)
class MyModelAdmin(admin.ModelAdmin):
    pass
}}}


Trying to create new object of MyModel with initial for created_at field:
`http://127.0.0.1:8000/admin/myapp/mymodel/add/?created_at=2024-10-10%2005%3A57%3A31`

Admin sites crashes with 500 error. This happens because the method `decompress` of the `SplitDateTimeWidget` expects an object of datetime type, but it is passed the string instead.

Proposed fix:



{{{
    def decompress(self, value):
        if isinstance(value, str):
            try:
                value = datetime.fromisoformat(value)
            except ValueError:
                return [None, None]
        if value:
            value = to_current_timezone(value)
            return [value.date(), value.time()]
        return [None, None]
}}}

"	Bug	new	Forms	5.1	Normal		SplitDateTimeWidget AdminSplitDateTime	Михаил Акопян	Unreviewed	1	0	0	0	0	0