Mabasej_Team/.venv/lib/python3.9/site-packages/pydantic/mypy.py
Untriex Programming ed6afdb5c9 new
2021-03-17 08:57:57 +01:00

691 lines
27 KiB
Python

from configparser import ConfigParser
from typing import Any, Callable, Dict, List, Optional, Set, Tuple, Type as TypingType, Union
from mypy.errorcodes import ErrorCode
from mypy.nodes import (
ARG_NAMED,
ARG_NAMED_OPT,
ARG_OPT,
ARG_POS,
ARG_STAR2,
MDEF,
Argument,
AssignmentStmt,
Block,
CallExpr,
ClassDef,
Context,
Decorator,
EllipsisExpr,
FuncBase,
FuncDef,
JsonDict,
MemberExpr,
NameExpr,
PassStmt,
PlaceholderNode,
RefExpr,
StrExpr,
SymbolNode,
SymbolTableNode,
TempNode,
TypeInfo,
TypeVarExpr,
Var,
)
from mypy.options import Options
from mypy.plugin import CheckerPluginInterface, ClassDefContext, MethodContext, Plugin, SemanticAnalyzerPluginInterface
from mypy.plugins import dataclasses
from mypy.semanal import set_callable_name # type: ignore
from mypy.server.trigger import make_wildcard_trigger
from mypy.types import (
AnyType,
CallableType,
Instance,
NoneType,
Type,
TypeOfAny,
TypeType,
TypeVarDef,
TypeVarType,
UnionType,
get_proper_type,
)
from mypy.typevars import fill_typevars
from mypy.util import get_unique_redefinition_name
CONFIGFILE_KEY = 'pydantic-mypy'
METADATA_KEY = 'pydantic-mypy-metadata'
BASEMODEL_FULLNAME = 'pydantic.main.BaseModel'
BASESETTINGS_FULLNAME = 'pydantic.env_settings.BaseSettings'
FIELD_FULLNAME = 'pydantic.fields.Field'
DATACLASS_FULLNAME = 'pydantic.dataclasses.dataclass'
def plugin(version: str) -> 'TypingType[Plugin]':
"""
`version` is the mypy version string
We might want to use this to print a warning if the mypy version being used is
newer, or especially older, than we expect (or need).
"""
return PydanticPlugin
class PydanticPlugin(Plugin):
def __init__(self, options: Options) -> None:
self.plugin_config = PydanticPluginConfig(options)
super().__init__(options)
def get_base_class_hook(self, fullname: str) -> 'Optional[Callable[[ClassDefContext], None]]':
sym = self.lookup_fully_qualified(fullname)
if sym and isinstance(sym.node, TypeInfo): # pragma: no branch
# No branching may occur if the mypy cache has not been cleared
if any(get_fullname(base) == BASEMODEL_FULLNAME for base in sym.node.mro):
return self._pydantic_model_class_maker_callback
return None
def get_method_hook(self, fullname: str) -> Optional[Callable[[MethodContext], Type]]:
if fullname.endswith('.from_orm'):
return from_orm_callback
return None
def get_class_decorator_hook(self, fullname: str) -> Optional[Callable[[ClassDefContext], None]]:
if fullname == DATACLASS_FULLNAME:
return dataclasses.dataclass_class_maker_callback
return None
def _pydantic_model_class_maker_callback(self, ctx: ClassDefContext) -> None:
transformer = PydanticModelTransformer(ctx, self.plugin_config)
transformer.transform()
class PydanticPluginConfig:
__slots__ = ('init_forbid_extra', 'init_typed', 'warn_required_dynamic_aliases', 'warn_untyped_fields')
init_forbid_extra: bool
init_typed: bool
warn_required_dynamic_aliases: bool
warn_untyped_fields: bool
def __init__(self, options: Options) -> None:
if options.config_file is None: # pragma: no cover
return
plugin_config = ConfigParser()
plugin_config.read(options.config_file)
for key in self.__slots__:
setting = plugin_config.getboolean(CONFIGFILE_KEY, key, fallback=False)
setattr(self, key, setting)
def from_orm_callback(ctx: MethodContext) -> Type:
"""
Raise an error if orm_mode is not enabled
"""
model_type: Instance
if isinstance(ctx.type, CallableType) and isinstance(ctx.type.ret_type, Instance):
model_type = ctx.type.ret_type # called on the class
elif isinstance(ctx.type, Instance):
model_type = ctx.type # called on an instance (unusual, but still valid)
else: # pragma: no cover
detail = f'ctx.type: {ctx.type} (of type {ctx.type.__class__.__name__})'
error_unexpected_behavior(detail, ctx.api, ctx.context)
return ctx.default_return_type
pydantic_metadata = model_type.type.metadata.get(METADATA_KEY)
if pydantic_metadata is None:
return ctx.default_return_type
orm_mode = pydantic_metadata.get('config', {}).get('orm_mode')
if orm_mode is not True:
error_from_orm(get_name(model_type.type), ctx.api, ctx.context)
return ctx.default_return_type
class PydanticModelTransformer:
tracked_config_fields: Set[str] = {
'extra',
'allow_mutation',
'frozen',
'orm_mode',
'allow_population_by_field_name',
'alias_generator',
}
def __init__(self, ctx: ClassDefContext, plugin_config: PydanticPluginConfig) -> None:
self._ctx = ctx
self.plugin_config = plugin_config
def transform(self) -> None:
"""
Configures the BaseModel subclass according to the plugin settings.
In particular:
* determines the model config and fields,
* adds a fields-aware signature for the initializer and construct methods
* freezes the class if allow_mutation = False or frozen = True
* stores the fields, config, and if the class is settings in the mypy metadata for access by subclasses
"""
ctx = self._ctx
info = self._ctx.cls.info
config = self.collect_config()
fields = self.collect_fields(config)
for field in fields:
if info[field.name].type is None:
if not ctx.api.final_iteration:
ctx.api.defer()
is_settings = any(get_fullname(base) == BASESETTINGS_FULLNAME for base in info.mro[:-1])
self.add_initializer(fields, config, is_settings)
self.add_construct_method(fields)
self.set_frozen(fields, frozen=config.allow_mutation is False or config.frozen is True)
info.metadata[METADATA_KEY] = {
'fields': {field.name: field.serialize() for field in fields},
'config': config.set_values_dict(),
}
def collect_config(self) -> 'ModelConfigData':
"""
Collects the values of the config attributes that are used by the plugin, accounting for parent classes.
"""
ctx = self._ctx
cls = ctx.cls
config = ModelConfigData()
for stmt in cls.defs.body:
if not isinstance(stmt, ClassDef):
continue
if stmt.name == 'Config':
for substmt in stmt.defs.body:
if not isinstance(substmt, AssignmentStmt):
continue
config.update(self.get_config_update(substmt))
if (
config.has_alias_generator
and not config.allow_population_by_field_name
and self.plugin_config.warn_required_dynamic_aliases
):
error_required_dynamic_aliases(ctx.api, stmt)
for info in cls.info.mro[1:]: # 0 is the current class
if METADATA_KEY not in info.metadata:
continue
# Each class depends on the set of fields in its ancestors
ctx.api.add_plugin_dependency(make_wildcard_trigger(get_fullname(info)))
for name, value in info.metadata[METADATA_KEY]['config'].items():
config.setdefault(name, value)
return config
def collect_fields(self, model_config: 'ModelConfigData') -> List['PydanticModelField']:
"""
Collects the fields for the model, accounting for parent classes
"""
# First, collect fields belonging to the current class.
ctx = self._ctx
cls = self._ctx.cls
fields = [] # type: List[PydanticModelField]
known_fields = set() # type: Set[str]
for stmt in cls.defs.body:
if not isinstance(stmt, AssignmentStmt): # `and stmt.new_syntax` to require annotation
continue
lhs = stmt.lvalues[0]
if not isinstance(lhs, NameExpr):
continue
if not stmt.new_syntax and self.plugin_config.warn_untyped_fields:
error_untyped_fields(ctx.api, stmt)
# if lhs.name == '__config__': # BaseConfig not well handled; I'm not sure why yet
# continue
sym = cls.info.names.get(lhs.name)
if sym is None: # pragma: no cover
# This is likely due to a star import (see the dataclasses plugin for a more detailed explanation)
# This is the same logic used in the dataclasses plugin
continue
node = sym.node
if isinstance(node, PlaceholderNode): # pragma: no cover
# See the PlaceholderNode docstring for more detail about how this can occur
# Basically, it is an edge case when dealing with complex import logic
# This is the same logic used in the dataclasses plugin
continue
if not isinstance(node, Var):
continue
# x: ClassVar[int] is ignored by dataclasses.
if node.is_classvar:
continue
is_required = self.get_is_required(cls, stmt, lhs)
alias, has_dynamic_alias = self.get_alias_info(stmt)
if (
has_dynamic_alias
and not model_config.allow_population_by_field_name
and self.plugin_config.warn_required_dynamic_aliases
):
error_required_dynamic_aliases(ctx.api, stmt)
fields.append(
PydanticModelField(
name=lhs.name,
is_required=is_required,
alias=alias,
has_dynamic_alias=has_dynamic_alias,
line=stmt.line,
column=stmt.column,
)
)
known_fields.add(lhs.name)
all_fields = fields.copy()
for info in cls.info.mro[1:]: # 0 is the current class, -2 is BaseModel, -1 is object
if METADATA_KEY not in info.metadata:
continue
superclass_fields = []
# Each class depends on the set of fields in its ancestors
ctx.api.add_plugin_dependency(make_wildcard_trigger(get_fullname(info)))
for name, data in info.metadata[METADATA_KEY]['fields'].items():
if name not in known_fields:
field = PydanticModelField.deserialize(info, data)
known_fields.add(name)
superclass_fields.append(field)
else:
(field,) = [a for a in all_fields if a.name == name]
all_fields.remove(field)
superclass_fields.append(field)
all_fields = superclass_fields + all_fields
return all_fields
def add_initializer(self, fields: List['PydanticModelField'], config: 'ModelConfigData', is_settings: bool) -> None:
"""
Adds a fields-aware `__init__` method to the class.
The added `__init__` will be annotated with types vs. all `Any` depending on the plugin settings.
"""
ctx = self._ctx
typed = self.plugin_config.init_typed
use_alias = config.allow_population_by_field_name is not True
force_all_optional = is_settings or bool(
config.has_alias_generator and not config.allow_population_by_field_name
)
init_arguments = self.get_field_arguments(
fields, typed=typed, force_all_optional=force_all_optional, use_alias=use_alias
)
if not self.should_init_forbid_extra(fields, config):
var = Var('kwargs')
init_arguments.append(Argument(var, AnyType(TypeOfAny.explicit), None, ARG_STAR2))
add_method(ctx, '__init__', init_arguments, NoneType())
def add_construct_method(self, fields: List['PydanticModelField']) -> None:
"""
Adds a fully typed `construct` classmethod to the class.
Similar to the fields-aware __init__ method, but always uses the field names (not aliases),
and does not treat settings fields as optional.
"""
ctx = self._ctx
set_str = ctx.api.named_type('__builtins__.set', [ctx.api.named_type('__builtins__.str')])
optional_set_str = UnionType([set_str, NoneType()])
fields_set_argument = Argument(Var('_fields_set', optional_set_str), optional_set_str, None, ARG_OPT)
construct_arguments = self.get_field_arguments(fields, typed=True, force_all_optional=False, use_alias=False)
construct_arguments = [fields_set_argument] + construct_arguments
obj_type = ctx.api.named_type('__builtins__.object')
self_tvar_name = '_PydanticBaseModel' # Make sure it does not conflict with other names in the class
tvar_fullname = ctx.cls.fullname + '.' + self_tvar_name
tvd = TypeVarDef(self_tvar_name, tvar_fullname, -1, [], obj_type)
self_tvar_expr = TypeVarExpr(self_tvar_name, tvar_fullname, [], obj_type)
ctx.cls.info.names[self_tvar_name] = SymbolTableNode(MDEF, self_tvar_expr)
self_type = TypeVarType(tvd)
add_method(
ctx,
'construct',
construct_arguments,
return_type=self_type,
self_type=self_type,
tvar_def=tvd,
is_classmethod=True,
)
def set_frozen(self, fields: List['PydanticModelField'], frozen: bool) -> None:
"""
Marks all fields as properties so that attempts to set them trigger mypy errors.
This is the same approach used by the attrs and dataclasses plugins.
"""
info = self._ctx.cls.info
for field in fields:
sym_node = info.names.get(field.name)
if sym_node is not None:
var = sym_node.node
assert isinstance(var, Var)
var.is_property = frozen
else:
var = field.to_var(info, use_alias=False)
var.info = info
var.is_property = frozen
var._fullname = get_fullname(info) + '.' + get_name(var)
info.names[get_name(var)] = SymbolTableNode(MDEF, var)
def get_config_update(self, substmt: AssignmentStmt) -> Optional['ModelConfigData']:
"""
Determines the config update due to a single statement in the Config class definition.
Warns if a tracked config attribute is set to a value the plugin doesn't know how to interpret (e.g., an int)
"""
lhs = substmt.lvalues[0]
if not (isinstance(lhs, NameExpr) and lhs.name in self.tracked_config_fields):
return None
if lhs.name == 'extra':
if isinstance(substmt.rvalue, StrExpr):
forbid_extra = substmt.rvalue.value == 'forbid'
elif isinstance(substmt.rvalue, MemberExpr):
forbid_extra = substmt.rvalue.name == 'forbid'
else:
error_invalid_config_value(lhs.name, self._ctx.api, substmt)
return None
return ModelConfigData(forbid_extra=forbid_extra)
if lhs.name == 'alias_generator':
has_alias_generator = True
if isinstance(substmt.rvalue, NameExpr) and substmt.rvalue.fullname == 'builtins.None':
has_alias_generator = False
return ModelConfigData(has_alias_generator=has_alias_generator)
if isinstance(substmt.rvalue, NameExpr) and substmt.rvalue.fullname in ('builtins.True', 'builtins.False'):
return ModelConfigData(**{lhs.name: substmt.rvalue.fullname == 'builtins.True'})
error_invalid_config_value(lhs.name, self._ctx.api, substmt)
return None
@staticmethod
def get_is_required(cls: ClassDef, stmt: AssignmentStmt, lhs: NameExpr) -> bool:
"""
Returns a boolean indicating whether the field defined in `stmt` is a required field.
"""
expr = stmt.rvalue
if isinstance(expr, TempNode):
# TempNode means annotation-only, so only non-required if Optional
value_type = get_proper_type(cls.info[lhs.name].type)
if isinstance(value_type, UnionType) and any(isinstance(item, NoneType) for item in value_type.items):
# Annotated as Optional, or otherwise having NoneType in the union
return False
return True
if isinstance(expr, CallExpr) and isinstance(expr.callee, RefExpr) and expr.callee.fullname == FIELD_FULLNAME:
# The "default value" is a call to `Field`; at this point, the field is
# only required if default is Ellipsis (i.e., `field_name: Annotation = Field(...)`)
return len(expr.args) > 0 and expr.args[0].__class__ is EllipsisExpr
# Only required if the "default value" is Ellipsis (i.e., `field_name: Annotation = ...`)
return isinstance(expr, EllipsisExpr)
@staticmethod
def get_alias_info(stmt: AssignmentStmt) -> Tuple[Optional[str], bool]:
"""
Returns a pair (alias, has_dynamic_alias), extracted from the declaration of the field defined in `stmt`.
`has_dynamic_alias` is True if and only if an alias is provided, but not as a string literal.
If `has_dynamic_alias` is True, `alias` will be None.
"""
expr = stmt.rvalue
if isinstance(expr, TempNode):
# TempNode means annotation-only
return None, False
if not (
isinstance(expr, CallExpr) and isinstance(expr.callee, RefExpr) and expr.callee.fullname == FIELD_FULLNAME
):
# Assigned value is not a call to pydantic.fields.Field
return None, False
for i, arg_name in enumerate(expr.arg_names):
if arg_name != 'alias':
continue
arg = expr.args[i]
if isinstance(arg, StrExpr):
return arg.value, False
else:
return None, True
return None, False
def get_field_arguments(
self, fields: List['PydanticModelField'], typed: bool, force_all_optional: bool, use_alias: bool
) -> List[Argument]:
"""
Helper function used during the construction of the `__init__` and `construct` method signatures.
Returns a list of mypy Argument instances for use in the generated signatures.
"""
info = self._ctx.cls.info
arguments = [
field.to_argument(info, typed=typed, force_optional=force_all_optional, use_alias=use_alias)
for field in fields
if not (use_alias and field.has_dynamic_alias)
]
return arguments
def should_init_forbid_extra(self, fields: List['PydanticModelField'], config: 'ModelConfigData') -> bool:
"""
Indicates whether the generated `__init__` should get a `**kwargs` at the end of its signature
We disallow arbitrary kwargs if the extra config setting is "forbid", or if the plugin config says to,
*unless* a required dynamic alias is present (since then we can't determine a valid signature).
"""
if not config.allow_population_by_field_name:
if self.is_dynamic_alias_present(fields, bool(config.has_alias_generator)):
return False
if config.forbid_extra:
return True
return self.plugin_config.init_forbid_extra
@staticmethod
def is_dynamic_alias_present(fields: List['PydanticModelField'], has_alias_generator: bool) -> bool:
"""
Returns whether any fields on the model have a "dynamic alias", i.e., an alias that cannot be
determined during static analysis.
"""
for field in fields:
if field.has_dynamic_alias:
return True
if has_alias_generator:
for field in fields:
if field.alias is None:
return True
return False
class PydanticModelField:
def __init__(
self, name: str, is_required: bool, alias: Optional[str], has_dynamic_alias: bool, line: int, column: int
):
self.name = name
self.is_required = is_required
self.alias = alias
self.has_dynamic_alias = has_dynamic_alias
self.line = line
self.column = column
def to_var(self, info: TypeInfo, use_alias: bool) -> Var:
name = self.name
if use_alias and self.alias is not None:
name = self.alias
return Var(name, info[self.name].type)
def to_argument(self, info: TypeInfo, typed: bool, force_optional: bool, use_alias: bool) -> Argument:
if typed and info[self.name].type is not None:
type_annotation = info[self.name].type
else:
type_annotation = AnyType(TypeOfAny.explicit)
return Argument(
variable=self.to_var(info, use_alias),
type_annotation=type_annotation,
initializer=None,
kind=ARG_NAMED_OPT if force_optional or not self.is_required else ARG_NAMED,
)
def serialize(self) -> JsonDict:
return self.__dict__
@classmethod
def deserialize(cls, info: TypeInfo, data: JsonDict) -> 'PydanticModelField':
return cls(**data)
class ModelConfigData:
def __init__(
self,
forbid_extra: Optional[bool] = None,
allow_mutation: Optional[bool] = None,
frozen: Optional[bool] = None,
orm_mode: Optional[bool] = None,
allow_population_by_field_name: Optional[bool] = None,
has_alias_generator: Optional[bool] = None,
):
self.forbid_extra = forbid_extra
self.allow_mutation = allow_mutation
self.frozen = frozen
self.orm_mode = orm_mode
self.allow_population_by_field_name = allow_population_by_field_name
self.has_alias_generator = has_alias_generator
def set_values_dict(self) -> Dict[str, Any]:
return {k: v for k, v in self.__dict__.items() if v is not None}
def update(self, config: Optional['ModelConfigData']) -> None:
if config is None:
return
for k, v in config.set_values_dict().items():
setattr(self, k, v)
def setdefault(self, key: str, value: Any) -> None:
if getattr(self, key) is None:
setattr(self, key, value)
ERROR_ORM = ErrorCode('pydantic-orm', 'Invalid from_orm call', 'Pydantic')
ERROR_CONFIG = ErrorCode('pydantic-config', 'Invalid config value', 'Pydantic')
ERROR_ALIAS = ErrorCode('pydantic-alias', 'Dynamic alias disallowed', 'Pydantic')
ERROR_UNEXPECTED = ErrorCode('pydantic-unexpected', 'Unexpected behavior', 'Pydantic')
ERROR_UNTYPED = ErrorCode('pydantic-field', 'Untyped field disallowed', 'Pydantic')
def error_from_orm(model_name: str, api: CheckerPluginInterface, context: Context) -> None:
api.fail(f'"{model_name}" does not have orm_mode=True', context, code=ERROR_ORM)
def error_invalid_config_value(name: str, api: SemanticAnalyzerPluginInterface, context: Context) -> None:
api.fail(f'Invalid value for "Config.{name}"', context, code=ERROR_CONFIG)
def error_required_dynamic_aliases(api: SemanticAnalyzerPluginInterface, context: Context) -> None:
api.fail('Required dynamic aliases disallowed', context, code=ERROR_ALIAS)
def error_unexpected_behavior(detail: str, api: CheckerPluginInterface, context: Context) -> None: # pragma: no cover
# Can't think of a good way to test this, but I confirmed it renders as desired by adding to a non-error path
link = 'https://github.com/samuelcolvin/pydantic/issues/new/choose'
full_message = f'The pydantic mypy plugin ran into unexpected behavior: {detail}\n'
full_message += f'Please consider reporting this bug at {link} so we can try to fix it!'
api.fail(full_message, context, code=ERROR_UNEXPECTED)
def error_untyped_fields(api: SemanticAnalyzerPluginInterface, context: Context) -> None:
api.fail('Untyped fields disallowed', context, code=ERROR_UNTYPED)
def add_method(
ctx: ClassDefContext,
name: str,
args: List[Argument],
return_type: Type,
self_type: Optional[Type] = None,
tvar_def: Optional[TypeVarDef] = None,
is_classmethod: bool = False,
is_new: bool = False,
# is_staticmethod: bool = False,
) -> None:
"""
Adds a new method to a class.
This can be dropped if/when https://github.com/python/mypy/issues/7301 is merged
"""
info = ctx.cls.info
# First remove any previously generated methods with the same name
# to avoid clashes and problems in the semantic analyzer.
if name in info.names:
sym = info.names[name]
if sym.plugin_generated and isinstance(sym.node, FuncDef):
ctx.cls.defs.body.remove(sym.node)
self_type = self_type or fill_typevars(info)
if is_classmethod or is_new:
first = [Argument(Var('_cls'), TypeType.make_normalized(self_type), None, ARG_POS)]
# elif is_staticmethod:
# first = []
else:
self_type = self_type or fill_typevars(info)
first = [Argument(Var('self'), self_type, None, ARG_POS)]
args = first + args
arg_types, arg_names, arg_kinds = [], [], []
for arg in args:
assert arg.type_annotation, 'All arguments must be fully typed.'
arg_types.append(arg.type_annotation)
arg_names.append(get_name(arg.variable))
arg_kinds.append(arg.kind)
function_type = ctx.api.named_type('__builtins__.function')
signature = CallableType(arg_types, arg_kinds, arg_names, return_type, function_type)
if tvar_def:
signature.variables = [tvar_def]
func = FuncDef(name, args, Block([PassStmt()]))
func.info = info
func.type = set_callable_name(signature, func)
func.is_class = is_classmethod
# func.is_static = is_staticmethod
func._fullname = get_fullname(info) + '.' + name
func.line = info.line
# NOTE: we would like the plugin generated node to dominate, but we still
# need to keep any existing definitions so they get semantically analyzed.
if name in info.names:
# Get a nice unique name instead.
r_name = get_unique_redefinition_name(name, info.names)
info.names[r_name] = info.names[name]
if is_classmethod: # or is_staticmethod:
func.is_decorated = True
v = Var(name, func.type)
v.info = info
v._fullname = func._fullname
# if is_classmethod:
v.is_classmethod = True
dec = Decorator(func, [NameExpr('classmethod')], v)
# else:
# v.is_staticmethod = True
# dec = Decorator(func, [NameExpr('staticmethod')], v)
dec.line = info.line
sym = SymbolTableNode(MDEF, dec)
else:
sym = SymbolTableNode(MDEF, func)
sym.plugin_generated = True
info.names[name] = sym
info.defn.defs.body.append(func)
def get_fullname(x: Union[FuncBase, SymbolNode]) -> str:
"""
Used for compatibility with mypy 0.740; can be dropped once support for 0.740 is dropped.
"""
fn = x.fullname
if callable(fn): # pragma: no cover
return fn()
return fn
def get_name(x: Union[FuncBase, SymbolNode]) -> str:
"""
Used for compatibility with mypy 0.740; can be dropped once support for 0.740 is dropped.
"""
fn = x.name
if callable(fn): # pragma: no cover
return fn()
return fn