Python types.ModuleType.__setattr__() Examples

def _reset_lazymodule(module, cls_attrs):
    """Resets a module's lazy state from cached data.

    """
    modclass = type(module)
    del modclass.__getattribute__
    del modclass.__setattr__
    try:
        del modclass._LOADING
    except AttributeError:
        pass
    for cls_attr in _CLS_ATTRS:
        try:
            setattr(modclass, cls_attr, cls_attrs[cls_attr])
        except KeyError:
            pass
    _reset_lazy_submod_refs(module) 

def __setattr__(self, attr, value):
        logger.debug("Setting attr {} to value {}, in LazyModule instance "
                     "of {}".format(attr, value, super(LazyModule, self)
                                    .__getattribute__("__name__")))
        _load_module(self)
        return super(LazyModule, self).__setattr__(attr, value) 

def carloverre():
    if verbose:
        print "Testing prohibition of Carlo Verre's hack..."
    try:
        object.__setattr__(str, "foo", 42)
    except TypeError:
        pass
    else:
        raise TestFailed, "Carlo Verre __setattr__ suceeded!"
    try:
        object.__delattr__(str, "lower")
    except TypeError:
        pass
    else:
        raise TestFailed, "Carlo Verre __delattr__ succeeded!" 

def pymods():
    if verbose: print "Testing Python subclass of module..."
    log = []
    from types import ModuleType as MT
    class MM(MT):
        def __init__(self, name):
            MT.__init__(self, name)
        def __getattribute__(self, name):
            log.append(("getattr", name))
            return MT.__getattribute__(self, name)
        def __setattr__(self, name, value):
            log.append(("setattr", name, value))
            MT.__setattr__(self, name, value)
        def __delattr__(self, name):
            log.append(("delattr", name))
            MT.__delattr__(self, name)
    a = MM("a")
    a.foo = 12
    x = a.foo
    del a.foo
    vereq(log, [("setattr", "foo", 12),
                ("getattr", "foo"),
                ("delattr", "foo")])

    # http://python.org/sf/1174712
    try:
        class Module(types.ModuleType, str):
            pass
    except TypeError:
        pass
    else:
        raise TestFailed("inheriting from ModuleType and str at the "
                          "same time should fail") 

def __setattr__(self, name, value):
        if hasattr(self, "env"):
            self.env[name] = value
        ModuleType.__setattr__(self, name, value) 

def carloverre():
    if verbose:
        print "Testing prohibition of Carlo Verre's hack..."
    try:
        object.__setattr__(str, "foo", 42)
    except TypeError:
        pass
    else:
        raise TestFailed, "Carlo Verre __setattr__ suceeded!"
    try:
        object.__delattr__(str, "lower")
    except TypeError:
        pass
    else:
        raise TestFailed, "Carlo Verre __delattr__ succeeded!" 

def pymods():
    if verbose: print "Testing Python subclass of module..."
    log = []
    from types import ModuleType as MT
    class MM(MT):
        def __init__(self, name):
            MT.__init__(self, name)
        def __getattribute__(self, name):
            log.append(("getattr", name))
            return MT.__getattribute__(self, name)
        def __setattr__(self, name, value):
            log.append(("setattr", name, value))
            MT.__setattr__(self, name, value)
        def __delattr__(self, name):
            log.append(("delattr", name))
            MT.__delattr__(self, name)
    a = MM("a")
    a.foo = 12
    x = a.foo
    del a.foo
    vereq(log, [("setattr", "foo", 12),
                ("getattr", "foo"),
                ("delattr", "foo")])

    # http://python.org/sf/1174712
    try:
        class Module(types.ModuleType, str):
            pass
    except TypeError:
        pass
    else:
        raise TestFailed("inheriting from ModuleType and str at the "
                          "same time should fail") 

def _reset_lazy_submod_refs(module):
    modclass = type(module)
    for deldict in _DELETION_DICT:
        try:
            resetnames = getattr(modclass, deldict)
        except AttributeError:
            continue
        for name, submod in resetnames.items(): 
            super(LazyModule, module).__setattr__(name, submod) 

def _clean_lazymodule(module):
    """Removes all lazy behavior from a module's class, for loading.

    Also removes all module attributes listed under the module's class deletion
    dictionaries. Deletion dictionaries are class attributes with names
    specified in `_DELETION_DICT`.

    Parameters
    ----------
    module: LazyModule 

    Returns
    -------
    dict
        A dictionary of deleted class attributes, that can be used to reset the
        lazy state using :func:`_reset_lazymodule`.
    """
    modclass = type(module)
    _clean_lazy_submod_refs(module)

    modclass.__getattribute__ = ModuleType.__getattribute__
    modclass.__setattr__ = ModuleType.__setattr__
    cls_attrs = {}
    for cls_attr in _CLS_ATTRS:
        try:
            cls_attrs[cls_attr] = getattr(modclass, cls_attr)
            delattr(modclass, cls_attr)
        except AttributeError:
            pass
    return cls_attrs 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def carloverre():
    if verbose:
        print "Testing prohibition of Carlo Verre's hack..."
    try:
        object.__setattr__(str, "foo", 42)
    except TypeError:
        pass
    else:
        raise TestFailed, "Carlo Verre __setattr__ suceeded!"
    try:
        object.__delattr__(str, "lower")
    except TypeError:
        pass
    else:
        raise TestFailed, "Carlo Verre __delattr__ succeeded!" 

def pymods():
    if verbose: print "Testing Python subclass of module..."
    log = []
    from types import ModuleType as MT
    class MM(MT):
        def __init__(self, name):
            MT.__init__(self, name)
        def __getattribute__(self, name):
            log.append(("getattr", name))
            return MT.__getattribute__(self, name)
        def __setattr__(self, name, value):
            log.append(("setattr", name, value))
            MT.__setattr__(self, name, value)
        def __delattr__(self, name):
            log.append(("delattr", name))
            MT.__delattr__(self, name)
    a = MM("a")
    a.foo = 12
    x = a.foo
    del a.foo
    vereq(log, [("setattr", "foo", 12),
                ("getattr", "foo"),
                ("delattr", "foo")])

    # http://python.org/sf/1174712
    try:
        class Module(types.ModuleType, str):
            pass
    except TypeError:
        pass
    else:
        raise TestFailed("inheriting from ModuleType and str at the "
                          "same time should fail") 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def __setattr__(self, name, value):
        #if hasattr(self, "instances"): self.instances[name] = value
        ModuleType.__setattr__(self, name, value) 

def overloading():
    if verbose: print "Testing operator overloading..."

    class B(object):
        "Intermediate class because object doesn't have a __setattr__"

    class C(B):

        def __getattr__(self, name):
            if name == "foo":
                return ("getattr", name)
            else:
                raise AttributeError
        def __setattr__(self, name, value):
            if name == "foo":
                self.setattr = (name, value)
            else:
                return B.__setattr__(self, name, value)
        def __delattr__(self, name):
            if name == "foo":
                self.delattr = name
            else:
                return B.__delattr__(self, name)

        def __getitem__(self, key):
            return ("getitem", key)
        def __setitem__(self, key, value):
            self.setitem = (key, value)
        def __delitem__(self, key):
            self.delitem = key

        def __getslice__(self, i, j):
            return ("getslice", i, j)
        def __setslice__(self, i, j, value):
            self.setslice = (i, j, value)
        def __delslice__(self, i, j):
            self.delslice = (i, j)

    a = C()
    vereq(a.foo, ("getattr", "foo"))
    a.foo = 12
    vereq(a.setattr, ("foo", 12))
    del a.foo
    vereq(a.delattr, "foo")

    vereq(a[12], ("getitem", 12))
    a[12] = 21
    vereq(a.setitem, (12, 21))
    del a[12]
    vereq(a.delitem, 12)

    vereq(a[0:10], ("getslice", 0, 10))
    a[0:10] = "foo"
    vereq(a.setslice, (0, 10, "foo"))
    del a[0:10]
    vereq(a.delslice, (0, 10)) 

def _lazy_module(modname, error_strings, lazy_mod_class):
    with _ImportLockContext():
        fullmodname = modname
        fullsubmodname = None
        # ensure parent module/package is in sys.modules
        # and parent.modname=module, as soon as the parent is imported   
        while modname:
            try:
                mod = sys.modules[modname]
                # We reached a (base) module that's already loaded. Let's stop
                # the cycle. Can't use 'break' because we still want to go 
                # through the fullsubmodname check below.
                modname = ''
            except KeyError:
                err_s = error_strings.copy()
                err_s.setdefault('module', modname)

                class _LazyModule(lazy_mod_class):
                    _lazy_import_error_msgs = {'msg': err_s.pop('msg')}
                    try:
                        _lazy_import_error_msgs['msg_callable'] = \
                                err_s.pop('msg_callable')
                    except KeyError:
                        pass
                    _lazy_import_error_strings = err_s
                    _lazy_import_callables = {}
                    _lazy_import_submodules = {}

                    def __repr__(self):
                        return "Lazily-loaded module {}".format(self.__name__)
                # A bit of cosmetic, to make AttributeErrors read more natural  
                _LazyModule.__name__ = 'module'
                # Actual module instantiation
                mod = sys.modules[modname] = _LazyModule(modname)
                # No need for __spec__. Maybe in the future.
                #if ModuleSpec:
                #    ModuleType.__setattr__(mod, '__spec__',
                #            ModuleSpec(modname, None))
            if fullsubmodname:
                submod = sys.modules[fullsubmodname]
                ModuleType.__setattr__(mod, submodname, submod)
                _LazyModule._lazy_import_submodules[submodname] = submod
            fullsubmodname = modname
            modname, _, submodname = modname.rpartition('.')
        return sys.modules[fullmodname] 

def overloading():
    if verbose: print "Testing operator overloading..."

    class B(object):
        "Intermediate class because object doesn't have a __setattr__"

    class C(B):

        def __getattr__(self, name):
            if name == "foo":
                return ("getattr", name)
            else:
                raise AttributeError
        def __setattr__(self, name, value):
            if name == "foo":
                self.setattr = (name, value)
            else:
                return B.__setattr__(self, name, value)
        def __delattr__(self, name):
            if name == "foo":
                self.delattr = name
            else:
                return B.__delattr__(self, name)

        def __getitem__(self, key):
            return ("getitem", key)
        def __setitem__(self, key, value):
            self.setitem = (key, value)
        def __delitem__(self, key):
            self.delitem = key

        def __getslice__(self, i, j):
            return ("getslice", i, j)
        def __setslice__(self, i, j, value):
            self.setslice = (i, j, value)
        def __delslice__(self, i, j):
            self.delslice = (i, j)

    a = C()
    vereq(a.foo, ("getattr", "foo"))
    a.foo = 12
    vereq(a.setattr, ("foo", 12))
    del a.foo
    vereq(a.delattr, "foo")

    vereq(a[12], ("getitem", 12))
    a[12] = 21
    vereq(a.setitem, (12, 21))
    del a[12]
    vereq(a.delitem, 12)

    vereq(a[0:10], ("getslice", 0, 10))
    a[0:10] = "foo"
    vereq(a.setslice, (0, 10, "foo"))
    del a[0:10]
    vereq(a.delslice, (0, 10)) 

def overloading():
    if verbose: print "Testing operator overloading..."

    class B(object):
        "Intermediate class because object doesn't have a __setattr__"

    class C(B):

        def __getattr__(self, name):
            if name == "foo":
                return ("getattr", name)
            else:
                raise AttributeError
        def __setattr__(self, name, value):
            if name == "foo":
                self.setattr = (name, value)
            else:
                return B.__setattr__(self, name, value)
        def __delattr__(self, name):
            if name == "foo":
                self.delattr = name
            else:
                return B.__delattr__(self, name)

        def __getitem__(self, key):
            return ("getitem", key)
        def __setitem__(self, key, value):
            self.setitem = (key, value)
        def __delitem__(self, key):
            self.delitem = key

        def __getslice__(self, i, j):
            return ("getslice", i, j)
        def __setslice__(self, i, j, value):
            self.setslice = (i, j, value)
        def __delslice__(self, i, j):
            self.delslice = (i, j)

    a = C()
    vereq(a.foo, ("getattr", "foo"))
    a.foo = 12
    vereq(a.setattr, ("foo", 12))
    del a.foo
    vereq(a.delattr, "foo")

    vereq(a[12], ("getitem", 12))
    a[12] = 21
    vereq(a.setitem, (12, 21))
    del a[12]
    vereq(a.delitem, 12)

    vereq(a[0:10], ("getslice", 0, 10))
    a[0:10] = "foo"
    vereq(a.setslice, (0, 10, "foo"))
    del a[0:10]
    vereq(a.delslice, (0, 10))