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Diffstat (limited to '.venv/lib/python3.12/site-packages/pydantic/fields.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/pydantic/fields.py | 1504 |
1 files changed, 1504 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/pydantic/fields.py b/.venv/lib/python3.12/site-packages/pydantic/fields.py new file mode 100644 index 00000000..9582685c --- /dev/null +++ b/.venv/lib/python3.12/site-packages/pydantic/fields.py @@ -0,0 +1,1504 @@ +"""Defining fields on models.""" + +from __future__ import annotations as _annotations + +import dataclasses +import inspect +import sys +import typing +from copy import copy +from dataclasses import Field as DataclassField +from functools import cached_property +from typing import Any, Callable, ClassVar, TypeVar, cast, overload +from warnings import warn + +import annotated_types +import typing_extensions +from pydantic_core import PydanticUndefined +from typing_extensions import Literal, TypeAlias, Unpack, deprecated + +from . import types +from ._internal import _decorators, _fields, _generics, _internal_dataclass, _repr, _typing_extra, _utils +from ._internal._namespace_utils import GlobalsNamespace, MappingNamespace +from .aliases import AliasChoices, AliasPath +from .config import JsonDict +from .errors import PydanticUserError +from .json_schema import PydanticJsonSchemaWarning +from .warnings import PydanticDeprecatedSince20 + +if typing.TYPE_CHECKING: + from ._internal._repr import ReprArgs +else: + # See PyCharm issues https://youtrack.jetbrains.com/issue/PY-21915 + # and https://youtrack.jetbrains.com/issue/PY-51428 + DeprecationWarning = PydanticDeprecatedSince20 + +__all__ = 'Field', 'PrivateAttr', 'computed_field' + + +_Unset: Any = PydanticUndefined + +if sys.version_info >= (3, 13): + import warnings + + Deprecated: TypeAlias = warnings.deprecated | deprecated +else: + Deprecated: TypeAlias = deprecated + + +class _FromFieldInfoInputs(typing_extensions.TypedDict, total=False): + """This class exists solely to add type checking for the `**kwargs` in `FieldInfo.from_field`.""" + + annotation: type[Any] | None + default_factory: Callable[[], Any] | Callable[[dict[str, Any]], Any] | None + alias: str | None + alias_priority: int | None + validation_alias: str | AliasPath | AliasChoices | None + serialization_alias: str | None + title: str | None + field_title_generator: Callable[[str, FieldInfo], str] | None + description: str | None + examples: list[Any] | None + exclude: bool | None + gt: annotated_types.SupportsGt | None + ge: annotated_types.SupportsGe | None + lt: annotated_types.SupportsLt | None + le: annotated_types.SupportsLe | None + multiple_of: float | None + strict: bool | None + min_length: int | None + max_length: int | None + pattern: str | typing.Pattern[str] | None + allow_inf_nan: bool | None + max_digits: int | None + decimal_places: int | None + union_mode: Literal['smart', 'left_to_right'] | None + discriminator: str | types.Discriminator | None + deprecated: Deprecated | str | bool | None + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None + frozen: bool | None + validate_default: bool | None + repr: bool + init: bool | None + init_var: bool | None + kw_only: bool | None + coerce_numbers_to_str: bool | None + fail_fast: bool | None + + +class _FieldInfoInputs(_FromFieldInfoInputs, total=False): + """This class exists solely to add type checking for the `**kwargs` in `FieldInfo.__init__`.""" + + default: Any + + +class FieldInfo(_repr.Representation): + """This class holds information about a field. + + `FieldInfo` is used for any field definition regardless of whether the [`Field()`][pydantic.fields.Field] + function is explicitly used. + + !!! warning + You generally shouldn't be creating `FieldInfo` directly, you'll only need to use it when accessing + [`BaseModel`][pydantic.main.BaseModel] `.model_fields` internals. + + Attributes: + annotation: The type annotation of the field. + default: The default value of the field. + default_factory: A callable to generate the default value. The callable can either take 0 arguments + (in which case it is called as is) or a single argument containing the already validated data. + alias: The alias name of the field. + alias_priority: The priority of the field's alias. + validation_alias: The validation alias of the field. + serialization_alias: The serialization alias of the field. + title: The title of the field. + field_title_generator: A callable that takes a field name and returns title for it. + description: The description of the field. + examples: List of examples of the field. + exclude: Whether to exclude the field from the model serialization. + discriminator: Field name or Discriminator for discriminating the type in a tagged union. + deprecated: A deprecation message, an instance of `warnings.deprecated` or the `typing_extensions.deprecated` backport, + or a boolean. If `True`, a default deprecation message will be emitted when accessing the field. + json_schema_extra: A dict or callable to provide extra JSON schema properties. + frozen: Whether the field is frozen. + validate_default: Whether to validate the default value of the field. + repr: Whether to include the field in representation of the model. + init: Whether the field should be included in the constructor of the dataclass. + init_var: Whether the field should _only_ be included in the constructor of the dataclass, and not stored. + kw_only: Whether the field should be a keyword-only argument in the constructor of the dataclass. + metadata: List of metadata constraints. + """ + + annotation: type[Any] | None + default: Any + default_factory: Callable[[], Any] | Callable[[dict[str, Any]], Any] | None + alias: str | None + alias_priority: int | None + validation_alias: str | AliasPath | AliasChoices | None + serialization_alias: str | None + title: str | None + field_title_generator: Callable[[str, FieldInfo], str] | None + description: str | None + examples: list[Any] | None + exclude: bool | None + discriminator: str | types.Discriminator | None + deprecated: Deprecated | str | bool | None + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None + frozen: bool | None + validate_default: bool | None + repr: bool + init: bool | None + init_var: bool | None + kw_only: bool | None + metadata: list[Any] + + __slots__ = ( + 'annotation', + 'evaluated', + 'default', + 'default_factory', + 'alias', + 'alias_priority', + 'validation_alias', + 'serialization_alias', + 'title', + 'field_title_generator', + 'description', + 'examples', + 'exclude', + 'discriminator', + 'deprecated', + 'json_schema_extra', + 'frozen', + 'validate_default', + 'repr', + 'init', + 'init_var', + 'kw_only', + 'metadata', + '_attributes_set', + ) + + # used to convert kwargs to metadata/constraints, + # None has a special meaning - these items are collected into a `PydanticGeneralMetadata` + metadata_lookup: ClassVar[dict[str, typing.Callable[[Any], Any] | None]] = { + 'strict': types.Strict, + 'gt': annotated_types.Gt, + 'ge': annotated_types.Ge, + 'lt': annotated_types.Lt, + 'le': annotated_types.Le, + 'multiple_of': annotated_types.MultipleOf, + 'min_length': annotated_types.MinLen, + 'max_length': annotated_types.MaxLen, + 'pattern': None, + 'allow_inf_nan': None, + 'max_digits': None, + 'decimal_places': None, + 'union_mode': None, + 'coerce_numbers_to_str': None, + 'fail_fast': types.FailFast, + } + + def __init__(self, **kwargs: Unpack[_FieldInfoInputs]) -> None: + """This class should generally not be initialized directly; instead, use the `pydantic.fields.Field` function + or one of the constructor classmethods. + + See the signature of `pydantic.fields.Field` for more details about the expected arguments. + """ + self._attributes_set = {k: v for k, v in kwargs.items() if v is not _Unset} + kwargs = {k: _DefaultValues.get(k) if v is _Unset else v for k, v in kwargs.items()} # type: ignore + self.annotation, annotation_metadata = self._extract_metadata(kwargs.get('annotation')) + self.evaluated = False + + default = kwargs.pop('default', PydanticUndefined) + if default is Ellipsis: + self.default = PydanticUndefined + # Also remove it from the attributes set, otherwise + # `GenerateSchema._common_field_schema` mistakenly + # uses it: + self._attributes_set.pop('default', None) + else: + self.default = default + + self.default_factory = kwargs.pop('default_factory', None) + + if self.default is not PydanticUndefined and self.default_factory is not None: + raise TypeError('cannot specify both default and default_factory') + + self.alias = kwargs.pop('alias', None) + self.validation_alias = kwargs.pop('validation_alias', None) + self.serialization_alias = kwargs.pop('serialization_alias', None) + alias_is_set = any(alias is not None for alias in (self.alias, self.validation_alias, self.serialization_alias)) + self.alias_priority = kwargs.pop('alias_priority', None) or 2 if alias_is_set else None + self.title = kwargs.pop('title', None) + self.field_title_generator = kwargs.pop('field_title_generator', None) + self.description = kwargs.pop('description', None) + self.examples = kwargs.pop('examples', None) + self.exclude = kwargs.pop('exclude', None) + self.discriminator = kwargs.pop('discriminator', None) + # For compatibility with FastAPI<=0.110.0, we preserve the existing value if it is not overridden + self.deprecated = kwargs.pop('deprecated', getattr(self, 'deprecated', None)) + self.repr = kwargs.pop('repr', True) + self.json_schema_extra = kwargs.pop('json_schema_extra', None) + self.validate_default = kwargs.pop('validate_default', None) + self.frozen = kwargs.pop('frozen', None) + # currently only used on dataclasses + self.init = kwargs.pop('init', None) + self.init_var = kwargs.pop('init_var', None) + self.kw_only = kwargs.pop('kw_only', None) + + self.metadata = self._collect_metadata(kwargs) + annotation_metadata # type: ignore + + @staticmethod + def from_field(default: Any = PydanticUndefined, **kwargs: Unpack[_FromFieldInfoInputs]) -> FieldInfo: + """Create a new `FieldInfo` object with the `Field` function. + + Args: + default: The default value for the field. Defaults to Undefined. + **kwargs: Additional arguments dictionary. + + Raises: + TypeError: If 'annotation' is passed as a keyword argument. + + Returns: + A new FieldInfo object with the given parameters. + + Example: + This is how you can create a field with default value like this: + + ```python + import pydantic + + class MyModel(pydantic.BaseModel): + foo: int = pydantic.Field(4) + ``` + """ + if 'annotation' in kwargs: + raise TypeError('"annotation" is not permitted as a Field keyword argument') + return FieldInfo(default=default, **kwargs) + + @staticmethod + def from_annotation(annotation: type[Any]) -> FieldInfo: + """Creates a `FieldInfo` instance from a bare annotation. + + This function is used internally to create a `FieldInfo` from a bare annotation like this: + + ```python + import pydantic + + class MyModel(pydantic.BaseModel): + foo: int # <-- like this + ``` + + We also account for the case where the annotation can be an instance of `Annotated` and where + one of the (not first) arguments in `Annotated` is an instance of `FieldInfo`, e.g.: + + ```python + import annotated_types + from typing_extensions import Annotated + + import pydantic + + class MyModel(pydantic.BaseModel): + foo: Annotated[int, annotated_types.Gt(42)] + bar: Annotated[int, pydantic.Field(gt=42)] + ``` + + Args: + annotation: An annotation object. + + Returns: + An instance of the field metadata. + """ + final = False + if _typing_extra.is_finalvar(annotation): + final = True + if annotation is not typing_extensions.Final: + annotation = typing_extensions.get_args(annotation)[0] + + if _typing_extra.is_annotated(annotation): + first_arg, *extra_args = typing_extensions.get_args(annotation) + if _typing_extra.is_finalvar(first_arg): + final = True + field_info_annotations = [a for a in extra_args if isinstance(a, FieldInfo)] + field_info = FieldInfo.merge_field_infos(*field_info_annotations, annotation=first_arg) + if field_info: + new_field_info = copy(field_info) + new_field_info.annotation = first_arg + new_field_info.frozen = final or field_info.frozen + metadata: list[Any] = [] + for a in extra_args: + if _typing_extra.is_deprecated_instance(a): + new_field_info.deprecated = a.message + elif not isinstance(a, FieldInfo): + metadata.append(a) + else: + metadata.extend(a.metadata) + new_field_info.metadata = metadata + return new_field_info + + return FieldInfo(annotation=annotation, frozen=final or None) # pyright: ignore[reportArgumentType] + + @staticmethod + def from_annotated_attribute(annotation: type[Any], default: Any) -> FieldInfo: + """Create `FieldInfo` from an annotation with a default value. + + This is used in cases like the following: + + ```python + import annotated_types + from typing_extensions import Annotated + + import pydantic + + class MyModel(pydantic.BaseModel): + foo: int = 4 # <-- like this + bar: Annotated[int, annotated_types.Gt(4)] = 4 # <-- or this + spam: Annotated[int, pydantic.Field(gt=4)] = 4 # <-- or this + ``` + + Args: + annotation: The type annotation of the field. + default: The default value of the field. + + Returns: + A field object with the passed values. + """ + if annotation is default: + raise PydanticUserError( + 'Error when building FieldInfo from annotated attribute. ' + "Make sure you don't have any field name clashing with a type annotation ", + code='unevaluable-type-annotation', + ) + + final = _typing_extra.is_finalvar(annotation) + if final and annotation is not typing_extensions.Final: + annotation = typing_extensions.get_args(annotation)[0] + + if isinstance(default, FieldInfo): + default.annotation, annotation_metadata = FieldInfo._extract_metadata(annotation) # pyright: ignore[reportArgumentType] + default.metadata += annotation_metadata + default = default.merge_field_infos( + *[x for x in annotation_metadata if isinstance(x, FieldInfo)], default, annotation=default.annotation + ) + default.frozen = final or default.frozen + return default + + if isinstance(default, dataclasses.Field): + init_var = False + if annotation is dataclasses.InitVar: + init_var = True + annotation = typing.cast(Any, Any) + elif isinstance(annotation, dataclasses.InitVar): + init_var = True + annotation = annotation.type + + pydantic_field = FieldInfo._from_dataclass_field(default) + pydantic_field.annotation, annotation_metadata = FieldInfo._extract_metadata(annotation) # pyright: ignore[reportArgumentType] + pydantic_field.metadata += annotation_metadata + pydantic_field = pydantic_field.merge_field_infos( + *[x for x in annotation_metadata if isinstance(x, FieldInfo)], + pydantic_field, + annotation=pydantic_field.annotation, + ) + pydantic_field.frozen = final or pydantic_field.frozen + pydantic_field.init_var = init_var + pydantic_field.init = getattr(default, 'init', None) + pydantic_field.kw_only = getattr(default, 'kw_only', None) + return pydantic_field + + if _typing_extra.is_annotated(annotation): + first_arg, *extra_args = typing_extensions.get_args(annotation) + field_infos = [a for a in extra_args if isinstance(a, FieldInfo)] + field_info = FieldInfo.merge_field_infos(*field_infos, annotation=first_arg, default=default) + metadata: list[Any] = [] + for a in extra_args: + if _typing_extra.is_deprecated_instance(a): + field_info.deprecated = a.message + elif not isinstance(a, FieldInfo): + metadata.append(a) + else: + metadata.extend(a.metadata) + field_info.metadata = metadata + return field_info + + return FieldInfo(annotation=annotation, default=default, frozen=final or None) # pyright: ignore[reportArgumentType] + + @staticmethod + def merge_field_infos(*field_infos: FieldInfo, **overrides: Any) -> FieldInfo: + """Merge `FieldInfo` instances keeping only explicitly set attributes. + + Later `FieldInfo` instances override earlier ones. + + Returns: + FieldInfo: A merged FieldInfo instance. + """ + if len(field_infos) == 1: + # No merging necessary, but we still need to make a copy and apply the overrides + field_info = copy(field_infos[0]) + field_info._attributes_set.update(overrides) + + default_override = overrides.pop('default', PydanticUndefined) + if default_override is Ellipsis: + default_override = PydanticUndefined + if default_override is not PydanticUndefined: + field_info.default = default_override + + for k, v in overrides.items(): + setattr(field_info, k, v) + return field_info # type: ignore + + merged_field_info_kwargs: dict[str, Any] = {} + metadata = {} + for field_info in field_infos: + attributes_set = field_info._attributes_set.copy() + + try: + json_schema_extra = attributes_set.pop('json_schema_extra') + existing_json_schema_extra = merged_field_info_kwargs.get('json_schema_extra') + + if existing_json_schema_extra is None: + merged_field_info_kwargs['json_schema_extra'] = json_schema_extra + if isinstance(existing_json_schema_extra, dict): + if isinstance(json_schema_extra, dict): + merged_field_info_kwargs['json_schema_extra'] = { + **existing_json_schema_extra, + **json_schema_extra, + } + if callable(json_schema_extra): + warn( + 'Composing `dict` and `callable` type `json_schema_extra` is not supported.' + 'The `callable` type is being ignored.' + "If you'd like support for this behavior, please open an issue on pydantic.", + PydanticJsonSchemaWarning, + ) + elif callable(json_schema_extra): + # if ever there's a case of a callable, we'll just keep the last json schema extra spec + merged_field_info_kwargs['json_schema_extra'] = json_schema_extra + except KeyError: + pass + + # later FieldInfo instances override everything except json_schema_extra from earlier FieldInfo instances + merged_field_info_kwargs.update(attributes_set) + + for x in field_info.metadata: + if not isinstance(x, FieldInfo): + metadata[type(x)] = x + + merged_field_info_kwargs.update(overrides) + field_info = FieldInfo(**merged_field_info_kwargs) + field_info.metadata = list(metadata.values()) + return field_info + + @staticmethod + def _from_dataclass_field(dc_field: DataclassField[Any]) -> FieldInfo: + """Return a new `FieldInfo` instance from a `dataclasses.Field` instance. + + Args: + dc_field: The `dataclasses.Field` instance to convert. + + Returns: + The corresponding `FieldInfo` instance. + + Raises: + TypeError: If any of the `FieldInfo` kwargs does not match the `dataclass.Field` kwargs. + """ + default = dc_field.default + if default is dataclasses.MISSING: + default = _Unset + + if dc_field.default_factory is dataclasses.MISSING: + default_factory = _Unset + else: + default_factory = dc_field.default_factory + + # use the `Field` function so in correct kwargs raise the correct `TypeError` + dc_field_metadata = {k: v for k, v in dc_field.metadata.items() if k in _FIELD_ARG_NAMES} + return Field(default=default, default_factory=default_factory, repr=dc_field.repr, **dc_field_metadata) # pyright: ignore[reportCallIssue] + + @staticmethod + def _extract_metadata(annotation: type[Any] | None) -> tuple[type[Any] | None, list[Any]]: + """Tries to extract metadata/constraints from an annotation if it uses `Annotated`. + + Args: + annotation: The type hint annotation for which metadata has to be extracted. + + Returns: + A tuple containing the extracted metadata type and the list of extra arguments. + """ + if annotation is not None: + if _typing_extra.is_annotated(annotation): + first_arg, *extra_args = typing_extensions.get_args(annotation) + return first_arg, list(extra_args) + + return annotation, [] + + @staticmethod + def _collect_metadata(kwargs: dict[str, Any]) -> list[Any]: + """Collect annotations from kwargs. + + Args: + kwargs: Keyword arguments passed to the function. + + Returns: + A list of metadata objects - a combination of `annotated_types.BaseMetadata` and + `PydanticMetadata`. + """ + metadata: list[Any] = [] + general_metadata = {} + for key, value in list(kwargs.items()): + try: + marker = FieldInfo.metadata_lookup[key] + except KeyError: + continue + + del kwargs[key] + if value is not None: + if marker is None: + general_metadata[key] = value + else: + metadata.append(marker(value)) + if general_metadata: + metadata.append(_fields.pydantic_general_metadata(**general_metadata)) + return metadata + + @property + def deprecation_message(self) -> str | None: + """The deprecation message to be emitted, or `None` if not set.""" + if self.deprecated is None: + return None + if isinstance(self.deprecated, bool): + return 'deprecated' if self.deprecated else None + return self.deprecated if isinstance(self.deprecated, str) else self.deprecated.message + + @property + def default_factory_takes_validated_data(self) -> bool | None: + """Whether the provided default factory callable has a validated data parameter. + + Returns `None` if no default factory is set. + """ + if self.default_factory is not None: + return _fields.takes_validated_data_argument(self.default_factory) + + @overload + def get_default( + self, *, call_default_factory: Literal[True], validated_data: dict[str, Any] | None = None + ) -> Any: ... + + @overload + def get_default(self, *, call_default_factory: Literal[False] = ...) -> Any: ... + + def get_default(self, *, call_default_factory: bool = False, validated_data: dict[str, Any] | None = None) -> Any: + """Get the default value. + + We expose an option for whether to call the default_factory (if present), as calling it may + result in side effects that we want to avoid. However, there are times when it really should + be called (namely, when instantiating a model via `model_construct`). + + Args: + call_default_factory: Whether to call the default factory or not. + validated_data: The already validated data to be passed to the default factory. + + Returns: + The default value, calling the default factory if requested or `None` if not set. + """ + if self.default_factory is None: + return _utils.smart_deepcopy(self.default) + elif call_default_factory: + if self.default_factory_takes_validated_data: + fac = cast('Callable[[dict[str, Any]], Any]', self.default_factory) + if validated_data is None: + raise ValueError( + "The default factory requires the 'validated_data' argument, which was not provided when calling 'get_default'." + ) + return fac(validated_data) + else: + fac = cast('Callable[[], Any]', self.default_factory) + return fac() + else: + return None + + def is_required(self) -> bool: + """Check if the field is required (i.e., does not have a default value or factory). + + Returns: + `True` if the field is required, `False` otherwise. + """ + return self.default is PydanticUndefined and self.default_factory is None + + def rebuild_annotation(self) -> Any: + """Attempts to rebuild the original annotation for use in function signatures. + + If metadata is present, it adds it to the original annotation using + `Annotated`. Otherwise, it returns the original annotation as-is. + + Note that because the metadata has been flattened, the original annotation + may not be reconstructed exactly as originally provided, e.g. if the original + type had unrecognized annotations, or was annotated with a call to `pydantic.Field`. + + Returns: + The rebuilt annotation. + """ + if not self.metadata: + return self.annotation + else: + # Annotated arguments must be a tuple + return typing_extensions.Annotated[(self.annotation, *self.metadata)] # type: ignore + + def apply_typevars_map( + self, + typevars_map: dict[Any, Any] | None, + globalns: GlobalsNamespace | None = None, + localns: MappingNamespace | None = None, + ) -> None: + """Apply a `typevars_map` to the annotation. + + This method is used when analyzing parametrized generic types to replace typevars with their concrete types. + + This method applies the `typevars_map` to the annotation in place. + + Args: + typevars_map: A dictionary mapping type variables to their concrete types. + globalns: The globals namespace to use during type annotation evaluation. + localns: The locals namespace to use during type annotation evaluation. + + See Also: + pydantic._internal._generics.replace_types is used for replacing the typevars with + their concrete types. + """ + annotation, _ = _typing_extra.try_eval_type(self.annotation, globalns, localns) + self.annotation = _generics.replace_types(annotation, typevars_map) + + def __repr_args__(self) -> ReprArgs: + yield 'annotation', _repr.PlainRepr(_repr.display_as_type(self.annotation)) + yield 'required', self.is_required() + + for s in self.__slots__: + # TODO: properly make use of the protocol (https://rich.readthedocs.io/en/stable/pretty.html#rich-repr-protocol) + # By yielding a three-tuple: + if s in ('_attributes_set', 'annotation', 'evaluated'): + continue + elif s == 'metadata' and not self.metadata: + continue + elif s == 'repr' and self.repr is True: + continue + if s == 'frozen' and self.frozen is False: + continue + if s == 'validation_alias' and self.validation_alias == self.alias: + continue + if s == 'serialization_alias' and self.serialization_alias == self.alias: + continue + if s == 'default' and self.default is not PydanticUndefined: + yield 'default', self.default + elif s == 'default_factory' and self.default_factory is not None: + yield 'default_factory', _repr.PlainRepr(_repr.display_as_type(self.default_factory)) + else: + value = getattr(self, s) + if value is not None and value is not PydanticUndefined: + yield s, value + + +class _EmptyKwargs(typing_extensions.TypedDict): + """This class exists solely to ensure that type checking warns about passing `**extra` in `Field`.""" + + +_DefaultValues = { + 'default': ..., + 'default_factory': None, + 'alias': None, + 'alias_priority': None, + 'validation_alias': None, + 'serialization_alias': None, + 'title': None, + 'description': None, + 'examples': None, + 'exclude': None, + 'discriminator': None, + 'json_schema_extra': None, + 'frozen': None, + 'validate_default': None, + 'repr': True, + 'init': None, + 'init_var': None, + 'kw_only': None, + 'pattern': None, + 'strict': None, + 'gt': None, + 'ge': None, + 'lt': None, + 'le': None, + 'multiple_of': None, + 'allow_inf_nan': None, + 'max_digits': None, + 'decimal_places': None, + 'min_length': None, + 'max_length': None, + 'coerce_numbers_to_str': None, +} + + +_T = TypeVar('_T') + + +# NOTE: Actual return type is 'FieldInfo', but we want to help type checkers +# to understand the magic that happens at runtime with the following overloads: +@overload # type hint the return value as `Any` to avoid type checking regressions when using `...`. +def Field( + default: ellipsis, # noqa: F821 # TODO: use `_typing_extra.EllipsisType` when we drop Py3.9 + *, + alias: str | None = _Unset, + alias_priority: int | None = _Unset, + validation_alias: str | AliasPath | AliasChoices | None = _Unset, + serialization_alias: str | None = _Unset, + title: str | None = _Unset, + field_title_generator: Callable[[str, FieldInfo], str] | None = _Unset, + description: str | None = _Unset, + examples: list[Any] | None = _Unset, + exclude: bool | None = _Unset, + discriminator: str | types.Discriminator | None = _Unset, + deprecated: Deprecated | str | bool | None = _Unset, + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None = _Unset, + frozen: bool | None = _Unset, + validate_default: bool | None = _Unset, + repr: bool = _Unset, + init: bool | None = _Unset, + init_var: bool | None = _Unset, + kw_only: bool | None = _Unset, + pattern: str | typing.Pattern[str] | None = _Unset, + strict: bool | None = _Unset, + coerce_numbers_to_str: bool | None = _Unset, + gt: annotated_types.SupportsGt | None = _Unset, + ge: annotated_types.SupportsGe | None = _Unset, + lt: annotated_types.SupportsLt | None = _Unset, + le: annotated_types.SupportsLe | None = _Unset, + multiple_of: float | None = _Unset, + allow_inf_nan: bool | None = _Unset, + max_digits: int | None = _Unset, + decimal_places: int | None = _Unset, + min_length: int | None = _Unset, + max_length: int | None = _Unset, + union_mode: Literal['smart', 'left_to_right'] = _Unset, + fail_fast: bool | None = _Unset, + **extra: Unpack[_EmptyKwargs], +) -> Any: ... +@overload # `default` argument set +def Field( + default: _T, + *, + alias: str | None = _Unset, + alias_priority: int | None = _Unset, + validation_alias: str | AliasPath | AliasChoices | None = _Unset, + serialization_alias: str | None = _Unset, + title: str | None = _Unset, + field_title_generator: Callable[[str, FieldInfo], str] | None = _Unset, + description: str | None = _Unset, + examples: list[Any] | None = _Unset, + exclude: bool | None = _Unset, + discriminator: str | types.Discriminator | None = _Unset, + deprecated: Deprecated | str | bool | None = _Unset, + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None = _Unset, + frozen: bool | None = _Unset, + validate_default: bool | None = _Unset, + repr: bool = _Unset, + init: bool | None = _Unset, + init_var: bool | None = _Unset, + kw_only: bool | None = _Unset, + pattern: str | typing.Pattern[str] | None = _Unset, + strict: bool | None = _Unset, + coerce_numbers_to_str: bool | None = _Unset, + gt: annotated_types.SupportsGt | None = _Unset, + ge: annotated_types.SupportsGe | None = _Unset, + lt: annotated_types.SupportsLt | None = _Unset, + le: annotated_types.SupportsLe | None = _Unset, + multiple_of: float | None = _Unset, + allow_inf_nan: bool | None = _Unset, + max_digits: int | None = _Unset, + decimal_places: int | None = _Unset, + min_length: int | None = _Unset, + max_length: int | None = _Unset, + union_mode: Literal['smart', 'left_to_right'] = _Unset, + fail_fast: bool | None = _Unset, + **extra: Unpack[_EmptyKwargs], +) -> _T: ... +@overload # `default_factory` argument set +def Field( + *, + default_factory: Callable[[], _T] | Callable[[dict[str, Any]], _T], + alias: str | None = _Unset, + alias_priority: int | None = _Unset, + validation_alias: str | AliasPath | AliasChoices | None = _Unset, + serialization_alias: str | None = _Unset, + title: str | None = _Unset, + field_title_generator: Callable[[str, FieldInfo], str] | None = _Unset, + description: str | None = _Unset, + examples: list[Any] | None = _Unset, + exclude: bool | None = _Unset, + discriminator: str | types.Discriminator | None = _Unset, + deprecated: Deprecated | str | bool | None = _Unset, + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None = _Unset, + frozen: bool | None = _Unset, + validate_default: bool | None = _Unset, + repr: bool = _Unset, + init: bool | None = _Unset, + init_var: bool | None = _Unset, + kw_only: bool | None = _Unset, + pattern: str | typing.Pattern[str] | None = _Unset, + strict: bool | None = _Unset, + coerce_numbers_to_str: bool | None = _Unset, + gt: annotated_types.SupportsGt | None = _Unset, + ge: annotated_types.SupportsGe | None = _Unset, + lt: annotated_types.SupportsLt | None = _Unset, + le: annotated_types.SupportsLe | None = _Unset, + multiple_of: float | None = _Unset, + allow_inf_nan: bool | None = _Unset, + max_digits: int | None = _Unset, + decimal_places: int | None = _Unset, + min_length: int | None = _Unset, + max_length: int | None = _Unset, + union_mode: Literal['smart', 'left_to_right'] = _Unset, + fail_fast: bool | None = _Unset, + **extra: Unpack[_EmptyKwargs], +) -> _T: ... +@overload +def Field( # No default set + *, + alias: str | None = _Unset, + alias_priority: int | None = _Unset, + validation_alias: str | AliasPath | AliasChoices | None = _Unset, + serialization_alias: str | None = _Unset, + title: str | None = _Unset, + field_title_generator: Callable[[str, FieldInfo], str] | None = _Unset, + description: str | None = _Unset, + examples: list[Any] | None = _Unset, + exclude: bool | None = _Unset, + discriminator: str | types.Discriminator | None = _Unset, + deprecated: Deprecated | str | bool | None = _Unset, + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None = _Unset, + frozen: bool | None = _Unset, + validate_default: bool | None = _Unset, + repr: bool = _Unset, + init: bool | None = _Unset, + init_var: bool | None = _Unset, + kw_only: bool | None = _Unset, + pattern: str | typing.Pattern[str] | None = _Unset, + strict: bool | None = _Unset, + coerce_numbers_to_str: bool | None = _Unset, + gt: annotated_types.SupportsGt | None = _Unset, + ge: annotated_types.SupportsGe | None = _Unset, + lt: annotated_types.SupportsLt | None = _Unset, + le: annotated_types.SupportsLe | None = _Unset, + multiple_of: float | None = _Unset, + allow_inf_nan: bool | None = _Unset, + max_digits: int | None = _Unset, + decimal_places: int | None = _Unset, + min_length: int | None = _Unset, + max_length: int | None = _Unset, + union_mode: Literal['smart', 'left_to_right'] = _Unset, + fail_fast: bool | None = _Unset, + **extra: Unpack[_EmptyKwargs], +) -> Any: ... +def Field( # noqa: C901 + default: Any = PydanticUndefined, + *, + default_factory: Callable[[], Any] | Callable[[dict[str, Any]], Any] | None = _Unset, + alias: str | None = _Unset, + alias_priority: int | None = _Unset, + validation_alias: str | AliasPath | AliasChoices | None = _Unset, + serialization_alias: str | None = _Unset, + title: str | None = _Unset, + field_title_generator: Callable[[str, FieldInfo], str] | None = _Unset, + description: str | None = _Unset, + examples: list[Any] | None = _Unset, + exclude: bool | None = _Unset, + discriminator: str | types.Discriminator | None = _Unset, + deprecated: Deprecated | str | bool | None = _Unset, + json_schema_extra: JsonDict | Callable[[JsonDict], None] | None = _Unset, + frozen: bool | None = _Unset, + validate_default: bool | None = _Unset, + repr: bool = _Unset, + init: bool | None = _Unset, + init_var: bool | None = _Unset, + kw_only: bool | None = _Unset, + pattern: str | typing.Pattern[str] | None = _Unset, + strict: bool | None = _Unset, + coerce_numbers_to_str: bool | None = _Unset, + gt: annotated_types.SupportsGt | None = _Unset, + ge: annotated_types.SupportsGe | None = _Unset, + lt: annotated_types.SupportsLt | None = _Unset, + le: annotated_types.SupportsLe | None = _Unset, + multiple_of: float | None = _Unset, + allow_inf_nan: bool | None = _Unset, + max_digits: int | None = _Unset, + decimal_places: int | None = _Unset, + min_length: int | None = _Unset, + max_length: int | None = _Unset, + union_mode: Literal['smart', 'left_to_right'] = _Unset, + fail_fast: bool | None = _Unset, + **extra: Unpack[_EmptyKwargs], +) -> Any: + """Usage docs: https://docs.pydantic.dev/2.10/concepts/fields + + Create a field for objects that can be configured. + + Used to provide extra information about a field, either for the model schema or complex validation. Some arguments + apply only to number fields (`int`, `float`, `Decimal`) and some apply only to `str`. + + Note: + - Any `_Unset` objects will be replaced by the corresponding value defined in the `_DefaultValues` dictionary. If a key for the `_Unset` object is not found in the `_DefaultValues` dictionary, it will default to `None` + + Args: + default: Default value if the field is not set. + default_factory: A callable to generate the default value. The callable can either take 0 arguments + (in which case it is called as is) or a single argument containing the already validated data. + alias: The name to use for the attribute when validating or serializing by alias. + This is often used for things like converting between snake and camel case. + alias_priority: Priority of the alias. This affects whether an alias generator is used. + validation_alias: Like `alias`, but only affects validation, not serialization. + serialization_alias: Like `alias`, but only affects serialization, not validation. + title: Human-readable title. + field_title_generator: A callable that takes a field name and returns title for it. + description: Human-readable description. + examples: Example values for this field. + exclude: Whether to exclude the field from the model serialization. + discriminator: Field name or Discriminator for discriminating the type in a tagged union. + deprecated: A deprecation message, an instance of `warnings.deprecated` or the `typing_extensions.deprecated` backport, + or a boolean. If `True`, a default deprecation message will be emitted when accessing the field. + json_schema_extra: A dict or callable to provide extra JSON schema properties. + frozen: Whether the field is frozen. If true, attempts to change the value on an instance will raise an error. + validate_default: If `True`, apply validation to the default value every time you create an instance. + Otherwise, for performance reasons, the default value of the field is trusted and not validated. + repr: A boolean indicating whether to include the field in the `__repr__` output. + init: Whether the field should be included in the constructor of the dataclass. + (Only applies to dataclasses.) + init_var: Whether the field should _only_ be included in the constructor of the dataclass. + (Only applies to dataclasses.) + kw_only: Whether the field should be a keyword-only argument in the constructor of the dataclass. + (Only applies to dataclasses.) + coerce_numbers_to_str: Whether to enable coercion of any `Number` type to `str` (not applicable in `strict` mode). + strict: If `True`, strict validation is applied to the field. + See [Strict Mode](../concepts/strict_mode.md) for details. + gt: Greater than. If set, value must be greater than this. Only applicable to numbers. + ge: Greater than or equal. If set, value must be greater than or equal to this. Only applicable to numbers. + lt: Less than. If set, value must be less than this. Only applicable to numbers. + le: Less than or equal. If set, value must be less than or equal to this. Only applicable to numbers. + multiple_of: Value must be a multiple of this. Only applicable to numbers. + min_length: Minimum length for iterables. + max_length: Maximum length for iterables. + pattern: Pattern for strings (a regular expression). + allow_inf_nan: Allow `inf`, `-inf`, `nan`. Only applicable to numbers. + max_digits: Maximum number of allow digits for strings. + decimal_places: Maximum number of decimal places allowed for numbers. + union_mode: The strategy to apply when validating a union. Can be `smart` (the default), or `left_to_right`. + See [Union Mode](../concepts/unions.md#union-modes) for details. + fail_fast: If `True`, validation will stop on the first error. If `False`, all validation errors will be collected. + This option can be applied only to iterable types (list, tuple, set, and frozenset). + extra: (Deprecated) Extra fields that will be included in the JSON schema. + + !!! warning Deprecated + The `extra` kwargs is deprecated. Use `json_schema_extra` instead. + + Returns: + A new [`FieldInfo`][pydantic.fields.FieldInfo]. The return annotation is `Any` so `Field` can be used on + type-annotated fields without causing a type error. + """ + # Check deprecated and removed params from V1. This logic should eventually be removed. + const = extra.pop('const', None) # type: ignore + if const is not None: + raise PydanticUserError('`const` is removed, use `Literal` instead', code='removed-kwargs') + + min_items = extra.pop('min_items', None) # type: ignore + if min_items is not None: + warn('`min_items` is deprecated and will be removed, use `min_length` instead', DeprecationWarning) + if min_length in (None, _Unset): + min_length = min_items # type: ignore + + max_items = extra.pop('max_items', None) # type: ignore + if max_items is not None: + warn('`max_items` is deprecated and will be removed, use `max_length` instead', DeprecationWarning) + if max_length in (None, _Unset): + max_length = max_items # type: ignore + + unique_items = extra.pop('unique_items', None) # type: ignore + if unique_items is not None: + raise PydanticUserError( + ( + '`unique_items` is removed, use `Set` instead' + '(this feature is discussed in https://github.com/pydantic/pydantic-core/issues/296)' + ), + code='removed-kwargs', + ) + + allow_mutation = extra.pop('allow_mutation', None) # type: ignore + if allow_mutation is not None: + warn('`allow_mutation` is deprecated and will be removed. use `frozen` instead', DeprecationWarning) + if allow_mutation is False: + frozen = True + + regex = extra.pop('regex', None) # type: ignore + if regex is not None: + raise PydanticUserError('`regex` is removed. use `pattern` instead', code='removed-kwargs') + + if extra: + warn( + 'Using extra keyword arguments on `Field` is deprecated and will be removed.' + ' Use `json_schema_extra` instead.' + f' (Extra keys: {", ".join(k.__repr__() for k in extra.keys())})', + DeprecationWarning, + ) + if not json_schema_extra or json_schema_extra is _Unset: + json_schema_extra = extra # type: ignore + + if ( + validation_alias + and validation_alias is not _Unset + and not isinstance(validation_alias, (str, AliasChoices, AliasPath)) + ): + raise TypeError('Invalid `validation_alias` type. it should be `str`, `AliasChoices`, or `AliasPath`') + + if serialization_alias in (_Unset, None) and isinstance(alias, str): + serialization_alias = alias + + if validation_alias in (_Unset, None): + validation_alias = alias + + include = extra.pop('include', None) # type: ignore + if include is not None: + warn('`include` is deprecated and does nothing. It will be removed, use `exclude` instead', DeprecationWarning) + + return FieldInfo.from_field( + default, + default_factory=default_factory, + alias=alias, + alias_priority=alias_priority, + validation_alias=validation_alias, + serialization_alias=serialization_alias, + title=title, + field_title_generator=field_title_generator, + description=description, + examples=examples, + exclude=exclude, + discriminator=discriminator, + deprecated=deprecated, + json_schema_extra=json_schema_extra, + frozen=frozen, + pattern=pattern, + validate_default=validate_default, + repr=repr, + init=init, + init_var=init_var, + kw_only=kw_only, + coerce_numbers_to_str=coerce_numbers_to_str, + strict=strict, + gt=gt, + ge=ge, + lt=lt, + le=le, + multiple_of=multiple_of, + min_length=min_length, + max_length=max_length, + allow_inf_nan=allow_inf_nan, + max_digits=max_digits, + decimal_places=decimal_places, + union_mode=union_mode, + fail_fast=fail_fast, + ) + + +_FIELD_ARG_NAMES = set(inspect.signature(Field).parameters) +_FIELD_ARG_NAMES.remove('extra') # do not include the varkwargs parameter + + +class ModelPrivateAttr(_repr.Representation): + """A descriptor for private attributes in class models. + + !!! warning + You generally shouldn't be creating `ModelPrivateAttr` instances directly, instead use + `pydantic.fields.PrivateAttr`. (This is similar to `FieldInfo` vs. `Field`.) + + Attributes: + default: The default value of the attribute if not provided. + default_factory: A callable function that generates the default value of the + attribute if not provided. + """ + + __slots__ = ('default', 'default_factory') + + def __init__( + self, default: Any = PydanticUndefined, *, default_factory: typing.Callable[[], Any] | None = None + ) -> None: + if default is Ellipsis: + self.default = PydanticUndefined + else: + self.default = default + self.default_factory = default_factory + + if not typing.TYPE_CHECKING: + # We put `__getattr__` in a non-TYPE_CHECKING block because otherwise, mypy allows arbitrary attribute access + + def __getattr__(self, item: str) -> Any: + """This function improves compatibility with custom descriptors by ensuring delegation happens + as expected when the default value of a private attribute is a descriptor. + """ + if item in {'__get__', '__set__', '__delete__'}: + if hasattr(self.default, item): + return getattr(self.default, item) + raise AttributeError(f'{type(self).__name__!r} object has no attribute {item!r}') + + def __set_name__(self, cls: type[Any], name: str) -> None: + """Preserve `__set_name__` protocol defined in https://peps.python.org/pep-0487.""" + default = self.default + if default is PydanticUndefined: + return + set_name = getattr(default, '__set_name__', None) + if callable(set_name): + set_name(cls, name) + + def get_default(self) -> Any: + """Retrieve the default value of the object. + + If `self.default_factory` is `None`, the method will return a deep copy of the `self.default` object. + + If `self.default_factory` is not `None`, it will call `self.default_factory` and return the value returned. + + Returns: + The default value of the object. + """ + return _utils.smart_deepcopy(self.default) if self.default_factory is None else self.default_factory() + + def __eq__(self, other: Any) -> bool: + return isinstance(other, self.__class__) and (self.default, self.default_factory) == ( + other.default, + other.default_factory, + ) + + +# NOTE: Actual return type is 'ModelPrivateAttr', but we want to help type checkers +# to understand the magic that happens at runtime. +@overload # `default` argument set +def PrivateAttr( + default: _T, + *, + init: Literal[False] = False, +) -> _T: ... +@overload # `default_factory` argument set +def PrivateAttr( + *, + default_factory: Callable[[], _T], + init: Literal[False] = False, +) -> _T: ... +@overload # No default set +def PrivateAttr( + *, + init: Literal[False] = False, +) -> Any: ... +def PrivateAttr( + default: Any = PydanticUndefined, + *, + default_factory: Callable[[], Any] | None = None, + init: Literal[False] = False, +) -> Any: + """Usage docs: https://docs.pydantic.dev/2.10/concepts/models/#private-model-attributes + + Indicates that an attribute is intended for private use and not handled during normal validation/serialization. + + Private attributes are not validated by Pydantic, so it's up to you to ensure they are used in a type-safe manner. + + Private attributes are stored in `__private_attributes__` on the model. + + Args: + default: The attribute's default value. Defaults to Undefined. + default_factory: Callable that will be + called when a default value is needed for this attribute. + If both `default` and `default_factory` are set, an error will be raised. + init: Whether the attribute should be included in the constructor of the dataclass. Always `False`. + + Returns: + An instance of [`ModelPrivateAttr`][pydantic.fields.ModelPrivateAttr] class. + + Raises: + ValueError: If both `default` and `default_factory` are set. + """ + if default is not PydanticUndefined and default_factory is not None: + raise TypeError('cannot specify both default and default_factory') + + return ModelPrivateAttr( + default, + default_factory=default_factory, + ) + + +@dataclasses.dataclass(**_internal_dataclass.slots_true) +class ComputedFieldInfo: + """A container for data from `@computed_field` so that we can access it while building the pydantic-core schema. + + Attributes: + decorator_repr: A class variable representing the decorator string, '@computed_field'. + wrapped_property: The wrapped computed field property. + return_type: The type of the computed field property's return value. + alias: The alias of the property to be used during serialization. + alias_priority: The priority of the alias. This affects whether an alias generator is used. + title: Title of the computed field to include in the serialization JSON schema. + field_title_generator: A callable that takes a field name and returns title for it. + description: Description of the computed field to include in the serialization JSON schema. + deprecated: A deprecation message, an instance of `warnings.deprecated` or the `typing_extensions.deprecated` backport, + or a boolean. If `True`, a default deprecation message will be emitted when accessing the field. + examples: Example values of the computed field to include in the serialization JSON schema. + json_schema_extra: A dict or callable to provide extra JSON schema properties. + repr: A boolean indicating whether to include the field in the __repr__ output. + """ + + decorator_repr: ClassVar[str] = '@computed_field' + wrapped_property: property + return_type: Any + alias: str | None + alias_priority: int | None + title: str | None + field_title_generator: typing.Callable[[str, ComputedFieldInfo], str] | None + description: str | None + deprecated: Deprecated | str | bool | None + examples: list[Any] | None + json_schema_extra: JsonDict | typing.Callable[[JsonDict], None] | None + repr: bool + + @property + def deprecation_message(self) -> str | None: + """The deprecation message to be emitted, or `None` if not set.""" + if self.deprecated is None: + return None + if isinstance(self.deprecated, bool): + return 'deprecated' if self.deprecated else None + return self.deprecated if isinstance(self.deprecated, str) else self.deprecated.message + + +def _wrapped_property_is_private(property_: cached_property | property) -> bool: # type: ignore + """Returns true if provided property is private, False otherwise.""" + wrapped_name: str = '' + + if isinstance(property_, property): + wrapped_name = getattr(property_.fget, '__name__', '') + elif isinstance(property_, cached_property): # type: ignore + wrapped_name = getattr(property_.func, '__name__', '') # type: ignore + + return wrapped_name.startswith('_') and not wrapped_name.startswith('__') + + +# this should really be `property[T], cached_property[T]` but property is not generic unlike cached_property +# See https://github.com/python/typing/issues/985 and linked issues +PropertyT = typing.TypeVar('PropertyT') + + +@typing.overload +def computed_field( + *, + alias: str | None = None, + alias_priority: int | None = None, + title: str | None = None, + field_title_generator: typing.Callable[[str, ComputedFieldInfo], str] | None = None, + description: str | None = None, + deprecated: Deprecated | str | bool | None = None, + examples: list[Any] | None = None, + json_schema_extra: JsonDict | typing.Callable[[JsonDict], None] | None = None, + repr: bool = True, + return_type: Any = PydanticUndefined, +) -> typing.Callable[[PropertyT], PropertyT]: ... + + +@typing.overload +def computed_field(__func: PropertyT) -> PropertyT: ... + + +def computed_field( + func: PropertyT | None = None, + /, + *, + alias: str | None = None, + alias_priority: int | None = None, + title: str | None = None, + field_title_generator: typing.Callable[[str, ComputedFieldInfo], str] | None = None, + description: str | None = None, + deprecated: Deprecated | str | bool | None = None, + examples: list[Any] | None = None, + json_schema_extra: JsonDict | typing.Callable[[JsonDict], None] | None = None, + repr: bool | None = None, + return_type: Any = PydanticUndefined, +) -> PropertyT | typing.Callable[[PropertyT], PropertyT]: + """Usage docs: https://docs.pydantic.dev/2.10/concepts/fields#the-computed_field-decorator + + Decorator to include `property` and `cached_property` when serializing models or dataclasses. + + This is useful for fields that are computed from other fields, or for fields that are expensive to compute and should be cached. + + ```python + from pydantic import BaseModel, computed_field + + class Rectangle(BaseModel): + width: int + length: int + + @computed_field + @property + def area(self) -> int: + return self.width * self.length + + print(Rectangle(width=3, length=2).model_dump()) + #> {'width': 3, 'length': 2, 'area': 6} + ``` + + If applied to functions not yet decorated with `@property` or `@cached_property`, the function is + automatically wrapped with `property`. Although this is more concise, you will lose IntelliSense in your IDE, + and confuse static type checkers, thus explicit use of `@property` is recommended. + + !!! warning "Mypy Warning" + Even with the `@property` or `@cached_property` applied to your function before `@computed_field`, + mypy may throw a `Decorated property not supported` error. + See [mypy issue #1362](https://github.com/python/mypy/issues/1362), for more information. + To avoid this error message, add `# type: ignore[misc]` to the `@computed_field` line. + + [pyright](https://github.com/microsoft/pyright) supports `@computed_field` without error. + + ```python + import random + + from pydantic import BaseModel, computed_field + + class Square(BaseModel): + width: float + + @computed_field + def area(self) -> float: # converted to a `property` by `computed_field` + return round(self.width**2, 2) + + @area.setter + def area(self, new_area: float) -> None: + self.width = new_area**0.5 + + @computed_field(alias='the magic number', repr=False) + def random_number(self) -> int: + return random.randint(0, 1_000) + + square = Square(width=1.3) + + # `random_number` does not appear in representation + print(repr(square)) + #> Square(width=1.3, area=1.69) + + print(square.random_number) + #> 3 + + square.area = 4 + + print(square.model_dump_json(by_alias=True)) + #> {"width":2.0,"area":4.0,"the magic number":3} + ``` + + !!! warning "Overriding with `computed_field`" + You can't override a field from a parent class with a `computed_field` in the child class. + `mypy` complains about this behavior if allowed, and `dataclasses` doesn't allow this pattern either. + See the example below: + + ```python + from pydantic import BaseModel, computed_field + + class Parent(BaseModel): + a: str + + try: + + class Child(Parent): + @computed_field + @property + def a(self) -> str: + return 'new a' + + except ValueError as e: + print(repr(e)) + #> ValueError("you can't override a field with a computed field") + ``` + + Private properties decorated with `@computed_field` have `repr=False` by default. + + ```python + from functools import cached_property + + from pydantic import BaseModel, computed_field + + class Model(BaseModel): + foo: int + + @computed_field + @cached_property + def _private_cached_property(self) -> int: + return -self.foo + + @computed_field + @property + def _private_property(self) -> int: + return -self.foo + + m = Model(foo=1) + print(repr(m)) + #> Model(foo=1) + ``` + + Args: + func: the function to wrap. + alias: alias to use when serializing this computed field, only used when `by_alias=True` + alias_priority: priority of the alias. This affects whether an alias generator is used + title: Title to use when including this computed field in JSON Schema + field_title_generator: A callable that takes a field name and returns title for it. + description: Description to use when including this computed field in JSON Schema, defaults to the function's + docstring + deprecated: A deprecation message (or an instance of `warnings.deprecated` or the `typing_extensions.deprecated` backport). + to be emitted when accessing the field. Or a boolean. This will automatically be set if the property is decorated with the + `deprecated` decorator. + examples: Example values to use when including this computed field in JSON Schema + json_schema_extra: A dict or callable to provide extra JSON schema properties. + repr: whether to include this computed field in model repr. + Default is `False` for private properties and `True` for public properties. + return_type: optional return for serialization logic to expect when serializing to JSON, if included + this must be correct, otherwise a `TypeError` is raised. + If you don't include a return type Any is used, which does runtime introspection to handle arbitrary + objects. + + Returns: + A proxy wrapper for the property. + """ + + def dec(f: Any) -> Any: + nonlocal description, deprecated, return_type, alias_priority + unwrapped = _decorators.unwrap_wrapped_function(f) + + if description is None and unwrapped.__doc__: + description = inspect.cleandoc(unwrapped.__doc__) + + if deprecated is None and hasattr(unwrapped, '__deprecated__'): + deprecated = unwrapped.__deprecated__ + + # if the function isn't already decorated with `@property` (or another descriptor), then we wrap it now + f = _decorators.ensure_property(f) + alias_priority = (alias_priority or 2) if alias is not None else None + + if repr is None: + repr_: bool = not _wrapped_property_is_private(property_=f) + else: + repr_ = repr + + dec_info = ComputedFieldInfo( + f, + return_type, + alias, + alias_priority, + title, + field_title_generator, + description, + deprecated, + examples, + json_schema_extra, + repr_, + ) + return _decorators.PydanticDescriptorProxy(f, dec_info) + + if func is None: + return dec + else: + return dec(func) |