# SPDX-License-Identifier: MIT """ Commonly used hooks for on_setattr. """ from . import _config from .exceptions import FrozenAttributeError def pipe(*setters): """ Run all *setters* and return the return value of the last one. .. versionadded:: 20.1.0 """ def wrapped_pipe(instance, attrib, new_value): rv = new_value for setter in setters: rv = setter(instance, attrib, rv) return rv return wrapped_pipe def frozen(_, __, ___): """ Prevent an attribute to be modified. .. versionadded:: 20.1.0 """ raise FrozenAttributeError() def validate(instance, attrib, new_value): """ Run *attrib*'s validator on *new_value* if it has one. .. versionadded:: 20.1.0 """ if _config._run_validators is False: return new_value v = attrib.validator if not v: return new_value v(instance, attrib, new_value) return new_value def convert(instance, attrib, new_value): """ Run *attrib*'s converter -- if it has one -- on *new_value* and return the result. .. versionadded:: 20.1.0 """ c = attrib.converter if c: return c(new_value) return new_value # Sentinel for disabling class-wide *on_setattr* hooks for certain attributes. # autodata stopped working, so the docstring is inlined in the API docs. NO_OP = object()