Setup models using HStoreManager.from_queryset(HStoreQuerySet)()

[benoitbryon]

As explained in https://docs.djangoproject.com/en/1.7/topics/db/managers/#from-queryset, when we have a custom manager and queryset classes, we can use manager's from_queryset() method.

Does this pattern apply here? I mean, in order to setup a model, the documentation currently tells:

class Something(models.Model):
    objects = hstore.HStoreManager()

Shouldn't it be something like this instead?

class Something(models.Model):
    objects = hstore.HStoreManager.from_queryset(hstore.HStoreQuerySet)()

In simplest use case, there is no issue with both setups.
But I encountered issues while using custom queryset and manager classes that inherit from HStoreManager and HStoreQuerySet. I'd like the following code to work:

class CustomQuerySet(hstore.HStoreQuerySet):
    def custom_query(self):
        """A custom method for both manager and queryset."""

class CustomManager(hstore.HStoreManager):
    def custom_manager(self):
        """A custom method for manager only."""

class CustomModel(models.Model):
    objects = CustomManager.from_queryset(CustomQuerySet)()

Is the code above valid?
If it is valid, then I think there is a bug in django-hstore: CustomModel.objects.custom_query raises some 'HStoreQuerySet' object has no attribute 'custom_query' error.

I guess that this is because HStoreManager.get_queryset() returns HStoreQuerySet whereas in my case I want it to return CustomQuerySet. So I had to alter CustomManager like that:

class CustomManager(hstore.HStoreManager):
    def get_queryset(self):
        return CustomQuerySet(self.model, using=self._db, hints=self._hints)

    def custom_manager(self):
        """A custom method for manager only."""

As I understand, things to change would be:

• HStoreManager doesn't implement custom get_queryset
• link between HStoreManager and HStoreQuerySet should be setup in model, typically using objects = hstore.HStoreManager.from_queryset(hstore.HStoreQuerySet)() (but could be adapted if users have custom manager and/or custom queryset) => documentation to be updated
• for backward compatibility, current HStoreManager.get_queryset should be renamed to HStoreManager.get_query_set()