for testing and deploying your application
for finding and fixing issues
for empowering human code reviews
"""Helper funtion for common pseudo-immutable use case."""
import inspect
import typing
MISSING = object()
def cant_modify(self: typing.Any, name: str) -> None:
"""Prevent attempts to modify an attr of the given name."""
class_repr = repr(self.__class__.__name__)
name_repr = repr(name)
if inspect.getattr_static(self, name, MISSING) is MISSING:
format_msg = "{class_repr} object has no attribute {name_repr}"
else:
format_msg = "{class_repr} object attribute {name_repr} is read-only"
raise AttributeError(format_msg.format(class_repr=class_repr, name_repr=name_repr))
def guard(instance: typing.Any, name: str) -> None:
"""Wrap up the common logic for using cant_modify."""
if not inspect.isdatadescriptor(inspect.getattr_static(instance, name, MISSING)):
cant_modify(instance, name)
mwchase /
python-structured-data
