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Diffstat (limited to 'third_party/python/attrs/attr/validators.py')
| -rw-r--r-- | third_party/python/attrs/attr/validators.py | 720 |
1 files changed, 720 insertions, 0 deletions
diff --git a/third_party/python/attrs/attr/validators.py b/third_party/python/attrs/attr/validators.py new file mode 100644 index 0000000000..1488554f78 --- /dev/null +++ b/third_party/python/attrs/attr/validators.py @@ -0,0 +1,720 @@ +# SPDX-License-Identifier: MIT + +""" +Commonly useful validators. +""" + + +import operator +import re + +from contextlib import contextmanager +from re import Pattern + +from ._config import get_run_validators, set_run_validators +from ._make import _AndValidator, and_, attrib, attrs +from .converters import default_if_none +from .exceptions import NotCallableError + + +__all__ = [ + "and_", + "deep_iterable", + "deep_mapping", + "disabled", + "ge", + "get_disabled", + "gt", + "in_", + "instance_of", + "is_callable", + "le", + "lt", + "matches_re", + "max_len", + "min_len", + "not_", + "optional", + "provides", + "set_disabled", +] + + +def set_disabled(disabled): + """ + Globally disable or enable running validators. + + By default, they are run. + + :param disabled: If ``True``, disable running all validators. + :type disabled: bool + + .. warning:: + + This function is not thread-safe! + + .. versionadded:: 21.3.0 + """ + set_run_validators(not disabled) + + +def get_disabled(): + """ + Return a bool indicating whether validators are currently disabled or not. + + :return: ``True`` if validators are currently disabled. + :rtype: bool + + .. versionadded:: 21.3.0 + """ + return not get_run_validators() + + +@contextmanager +def disabled(): + """ + Context manager that disables running validators within its context. + + .. warning:: + + This context manager is not thread-safe! + + .. versionadded:: 21.3.0 + """ + set_run_validators(False) + try: + yield + finally: + set_run_validators(True) + + +@attrs(repr=False, slots=True, hash=True) +class _InstanceOfValidator: + type = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if not isinstance(value, self.type): + raise TypeError( + "'{name}' must be {type!r} (got {value!r} that is a " + "{actual!r}).".format( + name=attr.name, + type=self.type, + actual=value.__class__, + value=value, + ), + attr, + self.type, + value, + ) + + def __repr__(self): + return "<instance_of validator for type {type!r}>".format( + type=self.type + ) + + +def instance_of(type): + """ + A validator that raises a `TypeError` if the initializer is called + with a wrong type for this particular attribute (checks are performed using + `isinstance` therefore it's also valid to pass a tuple of types). + + :param type: The type to check for. + :type type: type or tuple of type + + :raises TypeError: With a human readable error message, the attribute + (of type `attrs.Attribute`), the expected type, and the value it + got. + """ + return _InstanceOfValidator(type) + + +@attrs(repr=False, frozen=True, slots=True) +class _MatchesReValidator: + pattern = attrib() + match_func = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if not self.match_func(value): + raise ValueError( + "'{name}' must match regex {pattern!r}" + " ({value!r} doesn't)".format( + name=attr.name, pattern=self.pattern.pattern, value=value + ), + attr, + self.pattern, + value, + ) + + def __repr__(self): + return "<matches_re validator for pattern {pattern!r}>".format( + pattern=self.pattern + ) + + +def matches_re(regex, flags=0, func=None): + r""" + A validator that raises `ValueError` if the initializer is called + with a string that doesn't match *regex*. + + :param regex: a regex string or precompiled pattern to match against + :param int flags: flags that will be passed to the underlying re function + (default 0) + :param callable func: which underlying `re` function to call. Valid options + are `re.fullmatch`, `re.search`, and `re.match`; the default ``None`` + means `re.fullmatch`. For performance reasons, the pattern is always + precompiled using `re.compile`. + + .. versionadded:: 19.2.0 + .. versionchanged:: 21.3.0 *regex* can be a pre-compiled pattern. + """ + valid_funcs = (re.fullmatch, None, re.search, re.match) + if func not in valid_funcs: + raise ValueError( + "'func' must be one of {}.".format( + ", ".join( + sorted( + e and e.__name__ or "None" for e in set(valid_funcs) + ) + ) + ) + ) + + if isinstance(regex, Pattern): + if flags: + raise TypeError( + "'flags' can only be used with a string pattern; " + "pass flags to re.compile() instead" + ) + pattern = regex + else: + pattern = re.compile(regex, flags) + + if func is re.match: + match_func = pattern.match + elif func is re.search: + match_func = pattern.search + else: + match_func = pattern.fullmatch + + return _MatchesReValidator(pattern, match_func) + + +@attrs(repr=False, slots=True, hash=True) +class _ProvidesValidator: + interface = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if not self.interface.providedBy(value): + raise TypeError( + "'{name}' must provide {interface!r} which {value!r} " + "doesn't.".format( + name=attr.name, interface=self.interface, value=value + ), + attr, + self.interface, + value, + ) + + def __repr__(self): + return "<provides validator for interface {interface!r}>".format( + interface=self.interface + ) + + +def provides(interface): + """ + A validator that raises a `TypeError` if the initializer is called + with an object that does not provide the requested *interface* (checks are + performed using ``interface.providedBy(value)`` (see `zope.interface + <https://zopeinterface.readthedocs.io/en/latest/>`_). + + :param interface: The interface to check for. + :type interface: ``zope.interface.Interface`` + + :raises TypeError: With a human readable error message, the attribute + (of type `attrs.Attribute`), the expected interface, and the + value it got. + + .. deprecated:: 23.1.0 + """ + import warnings + + warnings.warn( + "attrs's zope-interface support is deprecated and will be removed in, " + "or after, April 2024.", + DeprecationWarning, + stacklevel=2, + ) + return _ProvidesValidator(interface) + + +@attrs(repr=False, slots=True, hash=True) +class _OptionalValidator: + validator = attrib() + + def __call__(self, inst, attr, value): + if value is None: + return + + self.validator(inst, attr, value) + + def __repr__(self): + return "<optional validator for {what} or None>".format( + what=repr(self.validator) + ) + + +def optional(validator): + """ + A validator that makes an attribute optional. An optional attribute is one + which can be set to ``None`` in addition to satisfying the requirements of + the sub-validator. + + :param Callable | tuple[Callable] | list[Callable] validator: A validator + (or validators) that is used for non-``None`` values. + + .. versionadded:: 15.1.0 + .. versionchanged:: 17.1.0 *validator* can be a list of validators. + .. versionchanged:: 23.1.0 *validator* can also be a tuple of validators. + """ + if isinstance(validator, (list, tuple)): + return _OptionalValidator(_AndValidator(validator)) + + return _OptionalValidator(validator) + + +@attrs(repr=False, slots=True, hash=True) +class _InValidator: + options = attrib() + + def __call__(self, inst, attr, value): + try: + in_options = value in self.options + except TypeError: # e.g. `1 in "abc"` + in_options = False + + if not in_options: + raise ValueError( + "'{name}' must be in {options!r} (got {value!r})".format( + name=attr.name, options=self.options, value=value + ), + attr, + self.options, + value, + ) + + def __repr__(self): + return "<in_ validator with options {options!r}>".format( + options=self.options + ) + + +def in_(options): + """ + A validator that raises a `ValueError` if the initializer is called + with a value that does not belong in the options provided. The check is + performed using ``value in options``. + + :param options: Allowed options. + :type options: list, tuple, `enum.Enum`, ... + + :raises ValueError: With a human readable error message, the attribute (of + type `attrs.Attribute`), the expected options, and the value it + got. + + .. versionadded:: 17.1.0 + .. versionchanged:: 22.1.0 + The ValueError was incomplete until now and only contained the human + readable error message. Now it contains all the information that has + been promised since 17.1.0. + """ + return _InValidator(options) + + +@attrs(repr=False, slots=False, hash=True) +class _IsCallableValidator: + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if not callable(value): + message = ( + "'{name}' must be callable " + "(got {value!r} that is a {actual!r})." + ) + raise NotCallableError( + msg=message.format( + name=attr.name, value=value, actual=value.__class__ + ), + value=value, + ) + + def __repr__(self): + return "<is_callable validator>" + + +def is_callable(): + """ + A validator that raises a `attrs.exceptions.NotCallableError` if the + initializer is called with a value for this particular attribute + that is not callable. + + .. versionadded:: 19.1.0 + + :raises attrs.exceptions.NotCallableError: With a human readable error + message containing the attribute (`attrs.Attribute`) name, + and the value it got. + """ + return _IsCallableValidator() + + +@attrs(repr=False, slots=True, hash=True) +class _DeepIterable: + member_validator = attrib(validator=is_callable()) + iterable_validator = attrib( + default=None, validator=optional(is_callable()) + ) + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if self.iterable_validator is not None: + self.iterable_validator(inst, attr, value) + + for member in value: + self.member_validator(inst, attr, member) + + def __repr__(self): + iterable_identifier = ( + "" + if self.iterable_validator is None + else f" {self.iterable_validator!r}" + ) + return ( + "<deep_iterable validator for{iterable_identifier}" + " iterables of {member!r}>" + ).format( + iterable_identifier=iterable_identifier, + member=self.member_validator, + ) + + +def deep_iterable(member_validator, iterable_validator=None): + """ + A validator that performs deep validation of an iterable. + + :param member_validator: Validator(s) to apply to iterable members + :param iterable_validator: Validator to apply to iterable itself + (optional) + + .. versionadded:: 19.1.0 + + :raises TypeError: if any sub-validators fail + """ + if isinstance(member_validator, (list, tuple)): + member_validator = and_(*member_validator) + return _DeepIterable(member_validator, iterable_validator) + + +@attrs(repr=False, slots=True, hash=True) +class _DeepMapping: + key_validator = attrib(validator=is_callable()) + value_validator = attrib(validator=is_callable()) + mapping_validator = attrib(default=None, validator=optional(is_callable())) + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if self.mapping_validator is not None: + self.mapping_validator(inst, attr, value) + + for key in value: + self.key_validator(inst, attr, key) + self.value_validator(inst, attr, value[key]) + + def __repr__(self): + return ( + "<deep_mapping validator for objects mapping {key!r} to {value!r}>" + ).format(key=self.key_validator, value=self.value_validator) + + +def deep_mapping(key_validator, value_validator, mapping_validator=None): + """ + A validator that performs deep validation of a dictionary. + + :param key_validator: Validator to apply to dictionary keys + :param value_validator: Validator to apply to dictionary values + :param mapping_validator: Validator to apply to top-level mapping + attribute (optional) + + .. versionadded:: 19.1.0 + + :raises TypeError: if any sub-validators fail + """ + return _DeepMapping(key_validator, value_validator, mapping_validator) + + +@attrs(repr=False, frozen=True, slots=True) +class _NumberValidator: + bound = attrib() + compare_op = attrib() + compare_func = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if not self.compare_func(value, self.bound): + raise ValueError( + "'{name}' must be {op} {bound}: {value}".format( + name=attr.name, + op=self.compare_op, + bound=self.bound, + value=value, + ) + ) + + def __repr__(self): + return "<Validator for x {op} {bound}>".format( + op=self.compare_op, bound=self.bound + ) + + +def lt(val): + """ + A validator that raises `ValueError` if the initializer is called + with a number larger or equal to *val*. + + :param val: Exclusive upper bound for values + + .. versionadded:: 21.3.0 + """ + return _NumberValidator(val, "<", operator.lt) + + +def le(val): + """ + A validator that raises `ValueError` if the initializer is called + with a number greater than *val*. + + :param val: Inclusive upper bound for values + + .. versionadded:: 21.3.0 + """ + return _NumberValidator(val, "<=", operator.le) + + +def ge(val): + """ + A validator that raises `ValueError` if the initializer is called + with a number smaller than *val*. + + :param val: Inclusive lower bound for values + + .. versionadded:: 21.3.0 + """ + return _NumberValidator(val, ">=", operator.ge) + + +def gt(val): + """ + A validator that raises `ValueError` if the initializer is called + with a number smaller or equal to *val*. + + :param val: Exclusive lower bound for values + + .. versionadded:: 21.3.0 + """ + return _NumberValidator(val, ">", operator.gt) + + +@attrs(repr=False, frozen=True, slots=True) +class _MaxLengthValidator: + max_length = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if len(value) > self.max_length: + raise ValueError( + "Length of '{name}' must be <= {max}: {len}".format( + name=attr.name, max=self.max_length, len=len(value) + ) + ) + + def __repr__(self): + return f"<max_len validator for {self.max_length}>" + + +def max_len(length): + """ + A validator that raises `ValueError` if the initializer is called + with a string or iterable that is longer than *length*. + + :param int length: Maximum length of the string or iterable + + .. versionadded:: 21.3.0 + """ + return _MaxLengthValidator(length) + + +@attrs(repr=False, frozen=True, slots=True) +class _MinLengthValidator: + min_length = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if len(value) < self.min_length: + raise ValueError( + "Length of '{name}' must be => {min}: {len}".format( + name=attr.name, min=self.min_length, len=len(value) + ) + ) + + def __repr__(self): + return f"<min_len validator for {self.min_length}>" + + +def min_len(length): + """ + A validator that raises `ValueError` if the initializer is called + with a string or iterable that is shorter than *length*. + + :param int length: Minimum length of the string or iterable + + .. versionadded:: 22.1.0 + """ + return _MinLengthValidator(length) + + +@attrs(repr=False, slots=True, hash=True) +class _SubclassOfValidator: + type = attrib() + + def __call__(self, inst, attr, value): + """ + We use a callable class to be able to change the ``__repr__``. + """ + if not issubclass(value, self.type): + raise TypeError( + "'{name}' must be a subclass of {type!r} " + "(got {value!r}).".format( + name=attr.name, + type=self.type, + value=value, + ), + attr, + self.type, + value, + ) + + def __repr__(self): + return "<subclass_of validator for type {type!r}>".format( + type=self.type + ) + + +def _subclass_of(type): + """ + A validator that raises a `TypeError` if the initializer is called + with a wrong type for this particular attribute (checks are performed using + `issubclass` therefore it's also valid to pass a tuple of types). + + :param type: The type to check for. + :type type: type or tuple of types + + :raises TypeError: With a human readable error message, the attribute + (of type `attrs.Attribute`), the expected type, and the value it + got. + """ + return _SubclassOfValidator(type) + + +@attrs(repr=False, slots=True, hash=True) +class _NotValidator: + validator = attrib() + msg = attrib( + converter=default_if_none( + "not_ validator child '{validator!r}' " + "did not raise a captured error" + ) + ) + exc_types = attrib( + validator=deep_iterable( + member_validator=_subclass_of(Exception), + iterable_validator=instance_of(tuple), + ), + ) + + def __call__(self, inst, attr, value): + try: + self.validator(inst, attr, value) + except self.exc_types: + pass # suppress error to invert validity + else: + raise ValueError( + self.msg.format( + validator=self.validator, + exc_types=self.exc_types, + ), + attr, + self.validator, + value, + self.exc_types, + ) + + def __repr__(self): + return ( + "<not_ validator wrapping {what!r}, " "capturing {exc_types!r}>" + ).format( + what=self.validator, + exc_types=self.exc_types, + ) + + +def not_(validator, *, msg=None, exc_types=(ValueError, TypeError)): + """ + A validator that wraps and logically 'inverts' the validator passed to it. + It will raise a `ValueError` if the provided validator *doesn't* raise a + `ValueError` or `TypeError` (by default), and will suppress the exception + if the provided validator *does*. + + Intended to be used with existing validators to compose logic without + needing to create inverted variants, for example, ``not_(in_(...))``. + + :param validator: A validator to be logically inverted. + :param msg: Message to raise if validator fails. + Formatted with keys ``exc_types`` and ``validator``. + :type msg: str + :param exc_types: Exception type(s) to capture. + Other types raised by child validators will not be intercepted and + pass through. + + :raises ValueError: With a human readable error message, + the attribute (of type `attrs.Attribute`), + the validator that failed to raise an exception, + the value it got, + and the expected exception types. + + .. versionadded:: 22.2.0 + """ + try: + exc_types = tuple(exc_types) + except TypeError: + exc_types = (exc_types,) + return _NotValidator(validator, msg, exc_types) |