Fixed adding hooks to fields defined in parent classes

[kevinastone]

Ran into a situation where I wanted to define a generic field in the parent class, but wanted to be able to override the value using a @compute hook in child classes.

It's not ideal having to clone any field you override, but it at least works correctly once you have the fields setup.

[coveralls]

Coverage remained the same at 60.4% when pulling 4d0c505 on kevinastone:hooks-in-subclasses into a62f43c on bninja:master.

[bninja]

not that its any better (still tedious) but u could do ~

class Item(pilo.Form):

    price = pilo.fields.Integer()

    @price.compute
    def price(self):
        return self.compute_price()

    def compute_price(self):
        return type(self).price._compute()


class Heirloom(Item):

    has_sentimental_value = pilo.fields.Boolean()

    def compute_price(self):
        return 1000000 if self.has_sentimental_value else 0

[bninja]

seems ok (hack workaround here if need it). but maybe a better interface would be ~:

class Item(pilo.Form):

    price = pilo.fields.Integer()


class Heirloom(Item):

    has_sentimental_value = pilo.fields.Boolean()

    @pilo.hook.compute
    def price(self):
        return 1000000 if self.has_sentimental_value else 0

don't know if it can be done (have base fields and names, so seems so). this looks like ~ extension of polymorphic stuff to field hooks.

[kevinastone]

From an API perspective, I think it would be better if the hook was offered late binding so I could simple register them such against the base class field.

class Item(pilo.Form):
    price = pilo.fields.Integer()

class Heirloom(Item):

    has_sentimental_value = pilo.fields.Boolean()

    @Item.price.compute
    def price(self):
        return 1000000 if self.has_sentimental_value else 0