Files
django-stubs/mypy_django_plugin/lib/sem_helpers.py
Maxim Kurnikov e5b61dc499 fix tests
2020-01-05 08:18:43 +03:00

121 lines
4.8 KiB
Python

from typing import List, NamedTuple, Optional, Tuple, Union, cast
from mypy.nodes import Argument, FuncDef, TypeInfo, Var
from mypy.plugin import ClassDefContext, DynamicClassDefContext
from mypy.plugins.common import add_method
from mypy.semanal import SemanticAnalyzer
from mypy.types import AnyType, CallableType, Instance, PlaceholderType
from mypy.types import Type as MypyType
from mypy.types import TypeOfAny, get_proper_type
class IncompleteDefnException(Exception):
def __init__(self, error_message: str = '') -> None:
super().__init__(error_message)
class BoundNameNotFound(IncompleteDefnException):
def __init__(self, fullname: str) -> None:
super().__init__(f'No {fullname!r} found')
def get_semanal_api(ctx: Union[ClassDefContext, DynamicClassDefContext]) -> SemanticAnalyzer:
return cast(SemanticAnalyzer, ctx.api)
def get_nested_meta_node_for_current_class(info: TypeInfo) -> Optional[TypeInfo]:
metaclass_sym = info.names.get('Meta')
if metaclass_sym is not None and isinstance(metaclass_sym.node, TypeInfo):
return metaclass_sym.node
return None
def prepare_unannotated_method_signature(method_node: FuncDef) -> Tuple[List[Argument], MypyType]:
prepared_arguments = []
for argument in method_node.arguments[1:]:
argument.type_annotation = AnyType(TypeOfAny.unannotated)
prepared_arguments.append(argument)
return_type = AnyType(TypeOfAny.unannotated)
return prepared_arguments, return_type
class SignatureTuple(NamedTuple):
arguments: List[Argument]
return_type: Optional[MypyType]
cannot_be_bound: bool
def analyze_callable_signature(api: SemanticAnalyzer, method_node: FuncDef) -> SignatureTuple:
method_type = method_node.type
assert isinstance(method_type, CallableType)
arguments = []
unbound = False
for arg_name, arg_type, original_argument in zip(method_type.arg_names[1:],
method_type.arg_types[1:],
method_node.arguments[1:]):
analyzed_arg_type = api.anal_type(get_proper_type(arg_type), allow_placeholder=True)
assert analyzed_arg_type is not None
if isinstance(analyzed_arg_type, PlaceholderType):
unbound = True
var = Var(name=original_argument.variable.name,
type=analyzed_arg_type)
var.set_line(original_argument.variable)
argument = Argument(variable=var,
type_annotation=analyzed_arg_type,
initializer=original_argument.initializer,
kind=original_argument.kind)
argument.set_line(original_argument)
arguments.append(argument)
analyzed_ret_type = api.anal_type(get_proper_type(method_type.ret_type), allow_placeholder=True)
assert analyzed_ret_type is not None
if isinstance(analyzed_ret_type, PlaceholderType):
unbound = True
return SignatureTuple(arguments, analyzed_ret_type, unbound)
def copy_method_or_incomplete_defn_exception(ctx: ClassDefContext,
self_type: Instance,
new_method_name: str,
method_node: FuncDef) -> None:
semanal_api = get_semanal_api(ctx)
if method_node.type is None:
if not semanal_api.final_iteration:
raise IncompleteDefnException(f'Unannotated method {method_node.fullname!r}')
arguments, return_type = prepare_unannotated_method_signature(method_node)
add_method(ctx,
new_method_name,
args=arguments,
return_type=return_type,
self_type=self_type)
return
assert isinstance(method_node.type, CallableType)
# copy global SymbolTableNode objects from original class to the current node, if not present
original_module = semanal_api.modules[method_node.info.module_name]
for name, sym in original_module.names.items():
if (not sym.plugin_generated
and name not in semanal_api.cur_mod_node.names):
semanal_api.add_imported_symbol(name, sym, context=semanal_api.cur_mod_node)
arguments, analyzed_return_type, unbound = analyze_callable_signature(semanal_api, method_node)
assert len(arguments) + 1 == len(method_node.arguments)
if unbound:
raise IncompleteDefnException(f'Signature of method {method_node.fullname!r} is not ready')
assert analyzed_return_type is not None
if new_method_name in ctx.cls.info.names:
del ctx.cls.info.names[new_method_name]
add_method(ctx,
new_method_name,
args=arguments,
return_type=analyzed_return_type,
self_type=self_type)