Customize attribute access for object

[dmazzella]

No description provided.

[dmazzella]

@dpgeorge #2755 how fix this?

[dmazzella]

@dpgeorge @pfalcon
in cPy:

>>> class A:
...     pass
...
>>> a = A()
>>> object.__setattr__(a, "a", 1)
>>> a
<__main__.A object at 0x6ffffa982e8>
>>> a.a
1
>>>

in uPy:

>>> class A:
...     pass
...
...
...
>>> a = A()
>>> object.__setattr__(a, "a", 1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: argument should be a 'object' not a 'A'
>>>

[dmazzella]

if i add this check to runtime.c:

if (arg0_type != self->type
            #if MICROPY_PY_OBJECT_METHODS_DELATTRS_SETATTRS
            && !mp_obj_is_subclass_fast(MP_OBJ_FROM_PTR(arg0_type), MP_OBJ_FROM_PTR(&mp_type_object))
            #endif
            ) { ...

but not directly subclass "object":

>>> class A:
...     pass
...
...
...
>>> a = A()
>>> object.__setattr__(a, "a", 1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: argument should be a 'object' not a 'A'
>>>

with subclass:

>>> class A(object):
...     pass
...
...
...
>>> a = A()
>>> object.__setattr__(a, "a", 1)
1
>>>