Python six 模块，create_bound_method() 实例源码

def test_create_bound_method():
    class X(object):
        pass
    def f(self):
        return self
    x = X()
    b = six.create_bound_method(f, x)
    assert isinstance(b, types.MethodType)
    assert b() is x

def __get__(self, instance, owner):
        if inspect.ismethoddescriptor(self.value) or inspect.isdatadescriptor(self.value):
            return self.value.__get__(instance, owner)
        if inspect.isfunction(self.value):
            if instance is None:
                return self
            else:
                return six.create_bound_method(self.value, instance)
        else:
            return self.value            


#------------------------------------------------[ CheckedInstance ]

def __get__(self, instance, owner):
        assert issubclass(owner, Stub), 'stubbed methods belong in Stub classes...'
        assert instance, 'implemented for instance methods only'
        real_method = getattr(owner.stubbed, self.stub.__name__)
        assert isinstance(real_method.im_func, types.FunctionType), 'stubbed methods are for methods...'
        real_args = inspect.getargspec(real_method.im_func)
        stub_args = inspect.getargspec(self.stub)
        assert real_args == stub_args, 'argument specification mismatch'

        return six.create_bound_method(self.stub, instance)

def __get__(self, instance, owner):
        self.bind_class(owner)
        if instance is None:
            return self
        else:
            return six.create_bound_method(self.function, instance)

def test_create_bound_method():
    class X(object):
        pass
    def f(self):
        return self
    x = X()
    b = six.create_bound_method(f, x)
    assert isinstance(b, types.MethodType)
    assert b() is x

def test_create_bound_method():
    class X(object):
        pass
    def f(self):
        return self
    x = X()
    b = six.create_bound_method(f, x)
    assert isinstance(b, types.MethodType)
    assert b() is x

def _getobj(self):
        # Regular object-making first
        obj = super(SpecInstance, self)._getobj()
        # Then decorate it with our parent's extra attributes, allowing nested
        # test classes to appear as an aggregate of parents' "scopes".
        # NOTE: need parent.parent due to instance->class hierarchy
        # NOTE: of course, skipping if we've gone out the top into a module etc
        if (
            not hasattr(self, 'parent') or
            not hasattr(self.parent, 'parent') or
            not isinstance(self.parent.parent, SpecInstance)
        ):
            return obj
        parent_obj = self.parent.parent.obj
        # Obtain parent attributes, etc not found on our obj (serves as both a
        # useful identifier of "stuff added to an outer class" and a way of
        # ensuring that we can override such attrs), and set them on obj
        delta = set(dir(parent_obj)).difference(set(dir(obj)))
        for name in delta:
            value = getattr(parent_obj, name)
            # Classes get skipped; they'd always just be other 'inner' classes
            # that we don't want to copy elsewhere.
            if isinstance(value, six.class_types):
                continue
            # Functions (methods) may get skipped, or not, depending:
            if isinstance(value, types.MethodType):
                # If they look like tests, they get skipped; don't want to copy
                # tests around!
                if istestfunction(name):
                    continue
                # Non-test == they're probably lifecycle methods
                # (setup/teardown) or helpers (_do_thing). Rebind them to the
                # target instance, otherwise the 'self' in the setup/helper is
                # not the same 'self' as that in the actual test method it runs
                # around or within!
                # TODO: arguably, all setup or helper methods should become
                # autouse class fixtures (see e.g. pytest docs under 'xunit
                # setup on steroids')
                func = six.get_method_function(value)
                setattr(obj, name, six.create_bound_method(func, obj))
            # Anything else should be some data-type attribute, which is copied
            # verbatim / by-value.
            else:
                setattr(obj, name, value)
        return obj