Hi all,
I came across a behaviour that somewhat surprised me on the model
fields. Namely, if you have a Field with no default value, an empty
value for that field is likely to be turned into the empty string by
Field.get_default.
I came across this behaviour writing unit tests for an applicatioin
I'm working on and where I was expecting my database to complain when
I created and saved an object with no values for one of its
'mandatory' fields. Or at least I expected it to be mandatory.
A quick example:
class DummyModel(models.Model):
mandatory_field = models.CharField(max_length=50)
optional_field = models.CharField(max_length=50, blank=True,
null=True)
empty_object = DummyModel()
empty_object.save()
I would expect this code to raise an IntegrityException -- and I'm
pretty sure it used to be the observed behaviour in older versions.
Instead, I find my database having a DummyModel entry with the empty
string value for mandatory_field and null for optional_field.
Is that not going against the 'madatory-ness' of the field
declaration? I have tried to tell: don't allow empty values for this
field and, obviously, it is not really enforced...
Am I expecting something that is not supposed to be provided by the
Field class but by the form class instead? At any rate, I don't see
why my None should be interpreted as the empty string. So here is my
question: what is the rational behind this behaviour?
cheers,
Rodrigue
Now, the
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