mirror of
https://github.com/thegeeklab/ansible-later.git
synced 2024-11-14 17:20:39 +00:00
79 lines
2.1 KiB
Python
79 lines
2.1 KiB
Python
"""
|
|
Commonly useful converters.
|
|
"""
|
|
|
|
from __future__ import absolute_import, division, print_function
|
|
|
|
from ._make import NOTHING, Factory
|
|
|
|
|
|
def optional(converter):
|
|
"""
|
|
A converter that allows an attribute to be optional. An optional attribute
|
|
is one which can be set to ``None``.
|
|
|
|
:param callable converter: the converter that is used for non-``None``
|
|
values.
|
|
|
|
.. versionadded:: 17.1.0
|
|
"""
|
|
|
|
def optional_converter(val):
|
|
if val is None:
|
|
return None
|
|
return converter(val)
|
|
|
|
return optional_converter
|
|
|
|
|
|
def default_if_none(default=NOTHING, factory=None):
|
|
"""
|
|
A converter that allows to replace ``None`` values by *default* or the
|
|
result of *factory*.
|
|
|
|
:param default: Value to be used if ``None`` is passed. Passing an instance
|
|
of :class:`attr.Factory` is supported, however the ``takes_self`` option
|
|
is *not*.
|
|
:param callable factory: A callable that takes not parameters whose result
|
|
is used if ``None`` is passed.
|
|
|
|
:raises TypeError: If **neither** *default* or *factory* is passed.
|
|
:raises TypeError: If **both** *default* and *factory* are passed.
|
|
:raises ValueError: If an instance of :class:`attr.Factory` is passed with
|
|
``takes_self=True``.
|
|
|
|
.. versionadded:: 18.2.0
|
|
"""
|
|
if default is NOTHING and factory is None:
|
|
raise TypeError("Must pass either `default` or `factory`.")
|
|
|
|
if default is not NOTHING and factory is not None:
|
|
raise TypeError(
|
|
"Must pass either `default` or `factory` but not both."
|
|
)
|
|
|
|
if factory is not None:
|
|
default = Factory(factory)
|
|
|
|
if isinstance(default, Factory):
|
|
if default.takes_self:
|
|
raise ValueError(
|
|
"`takes_self` is not supported by default_if_none."
|
|
)
|
|
|
|
def default_if_none_converter(val):
|
|
if val is not None:
|
|
return val
|
|
|
|
return default.factory()
|
|
|
|
else:
|
|
|
|
def default_if_none_converter(val):
|
|
if val is not None:
|
|
return val
|
|
|
|
return default
|
|
|
|
return default_if_none_converter
|