What steps will reproduce the problem?

>>> a = Mock() >>> a.this = ‘that’ >>> del a.this >>> a.this = ‘that’

>>> del a.this Traceback (most recent call last): ... AttributeError: this

What is the expected output? What do you see instead? I would expect it to happily delete the attribute this. Instead it raises and attribute error.

What version of the product are you using? On what operating system? mock-1.0.1-py2.7 Red Hat Enterprise Linux Server release 5.5

Please provide any additional information below.

suggested change:

Previous:

def __delattr__(self, name):
    if name in _all_magics and name in type(self).__dict__:
        delattr(type(self), name)
        if name not in self.__dict__:
            # for magic methods that are still MagicProxy objects and
            # not set on the instance itself
            return

    if name in self.__dict__:
        object.__delattr__(self, name)

    obj = self._mock_children.get(name, _missing)
    if obj is _deleted:
        raise AttributeError(name)
    if obj is not _missing:
        del self._mock_children[name]
    self._mock_children[name] = _deleted

Change:

def __delattr__(self, name):
    if name in _all_magics and name in type(self).__dict__:
        delattr(type(self), name)
        if name not in self.__dict__:
            # for magic methods that are still MagicProxy objects and
            # not set on the instance itself
            return

    obj = self._mock_children.get(name, _missing)
    if name in self.__dict__:
        object.__delattr__(self, name)
    elif obj is _deleted:
        raise AttributeError(name)
    if obj is not _missing:
        del self._mock_children[name]
    self._mock_children[name] = _deleted

Incidentally the if ‘obj is not _missing’ line seems superfluous.

Thanks for the report. I've posted it on the Python bug tracker (as mock is in the Python standard library as well) as http://bugs.python.org/issue20239