| # 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() | |