verifyClass(IAdapterRegistry, AdapterRegistry)...

[liveFreeOrCode]

from zope.interface.adapter import AdapterRegistry, IAdapterRegistry

verifyClass(IAdapterRegistry, AdapterRegistry)
...
MultipleInvalid: The object <class 'zope.interface.adapter.AdapterRegistry'> has failed to implement interface <InterfaceClass zope.interface.interfaces.IAdapterRegistry>:
    The zope.interface.interfaces.IAdapterRegistry.lookup(required, provided, name='', default=None) attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.queryMultiAdapter(objects, provided, name='', default=None) attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.lookup1(required, provided, name='', default=None) attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.queryAdapter(object, provided, name='', default=None) attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.adapter_hook(provided, object, name='', default=None) attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.lookupAll(required, provided) attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.names(required, provided) attribute was not provided
    The contract of zope.interface.interfaces.IAdapterRegistry.subscribe(required, provided, subscriber, name='') is violated because 'BaseAdapterRegistry.subscribe(self, required, provided, value)' doesn't allow enough arguments
    The zope.interface.interfaces.IAdapterRegistry.subscriptions(required, provided, name='') attribute was not provided
    The zope.interface.interfaces.IAdapterRegistry.subscribers(objects, provided, name='') attribute was not provided

Is there something I'm missing?

[jamadden]

verifyClass can only check whether a class statically meets the requirements of an interface. AdapterRegistry does not statically meet the requirements of IAdapterRegistry, and verifyClass is correct to point that out. For example:

>>> from zope.interface.adapter import AdapterRegistry
>>> AdapterRegistry.lookup
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: type object 'AdapterRegistry' has no attribute 'lookup'

This is because many attributes are delegated to a different object at runtime; that's part of the difference between implements and provides.

zope.interface/src/zope/interface/adapter.py

Lines 117 to 120 in 10a951f

	def _createLookup(self):
	self._v_lookup = self.LookupClass(self)
	for name in self._delegated:
	self.__dict__[name] = getattr(self._v_lookup, name)

(#15 is somewhat similar).

Given the dynamic nature of python, and the distinction between implements and provides verifyObject is a better fit here.

However, even doing that does appear to reveal a discrepancy:

>>> from zope.interface import *
>>> from zope.interface.adapter import *
>>> from zope.interface.verify import *
>>> from zope.interface.interfaces import IAdapterRegistry
>>> verifyObject(IAdapterRegistry, AdapterRegistry())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "//zope.interface/src/zope/interface/verify.py", line 172, in verifyObject
    return _verify(iface, candidate, tentative, vtype='o')
  File "//zope.interface/src/zope/interface/verify.py", line 92, in _verify
    raise MultipleInvalid(iface, candidate, excs)
zope.interface.exceptions.MultipleInvalid: The object <zope.interface.adapter.AdapterRegistry object at 0x10e8fd2d0> has failed to implement interface <InterfaceClass zope.interface.interfaces.IAdapterRegistry>:
    The contract of zope.interface.interfaces.IAdapterRegistry.subscribe(required, provided, subscriber, name='') is violated because 'BaseAdapterRegistry.subscribe(required, provided, value)' doesn't allow enough arguments
    The contract of zope.interface.interfaces.IAdapterRegistry.subscribers(objects, provided, name='') is violated because 'AdapterLookupBase.subscribers(objects, provided)' doesn't allow enough arguments

I don't know if this is due to a limitation in C extension methods, or to a problem in the interface definition. On a quick examination, it appears to be a problem with the interface.

>>> reg = AdapterRegistry()
>>> reg.subscribe
<bound method BaseAdapterRegistry.subscribe of <zope.interface.adapter.AdapterRegistry object at 0x10e91f960>>
>>> help(reg.subscribe)
Help on method subscribe in module zope.interface.adapter:

subscribe(required, provided, value) method of zope.interface.adapter.AdapterRegistry instance

None
>>> reg.subscribe('req', 'prov', 'val', 'name')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: subscribe() takes 4 positional arguments but 5 were given
>>> reg.subscribe('req', 'prov', 'val', name='name')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: subscribe() got an unexpected keyword argument 'name'