def resolve_lookup_into_field(self, model_cls: Type[Model], lookup: str) -> Union[Field, ForeignObjectRel]:
query = Query(model_cls)
lookup_parts, field_parts, is_expression = query.solve_lookup_type(lookup)
if lookup_parts:
raise LookupsAreUnsupported()
return self._resolve_field_from_parts(field_parts, model_cls)
def resolve_lookup(self, model_cls: Type[Model], lookup: str) -> Field:
query = Query(model_cls)
lookup_parts, field_parts, is_expression = query.solve_lookup_type(
lookup)
if lookup_parts:
raise FieldError('Lookups not supported yet')
currently_observed_model = model_cls
current_field = None
for field_part in field_parts:
if field_part == 'pk':
return self.django_context.get_primary_key_field(
currently_observed_model)
current_field = currently_observed_model._meta.get_field(
field_part)
if not isinstance(current_field, (ForeignObjectRel, RelatedField)):
continue
currently_observed_model = self.django_context.fields_context.get_related_model_cls(
current_field)
if isinstance(current_field, ForeignObjectRel):
current_field = self.django_context.get_primary_key_field(
currently_observed_model)
# if it is None, solve_lookup_type() will fail earlier
assert current_field is not None
return current_field
def resolve_lookup_expected_type(self, ctx: MethodContext,
model_cls: Type[Model],
lookup: str) -> MypyType:
query = Query(model_cls)
try:
lookup_parts, field_parts, is_expression = query.solve_lookup_type(
lookup)
if is_expression:
return AnyType(TypeOfAny.explicit)
except FieldError as exc:
ctx.api.fail(exc.args[0], ctx.context)
return AnyType(TypeOfAny.from_error)
field = self._resolve_field_from_parts(field_parts, model_cls)
lookup_cls = None
if lookup_parts:
lookup = lookup_parts[-1]
lookup_cls = field.get_lookup(lookup)
if lookup_cls is None:
# unknown lookup
return AnyType(TypeOfAny.explicit)
if lookup_cls is None or isinstance(lookup_cls, Exact):
return self.get_field_lookup_exact_type(
helpers.get_typechecker_api(ctx), field)
assert lookup_cls is not None
lookup_info = helpers.lookup_class_typeinfo(
helpers.get_typechecker_api(ctx), lookup_cls)
if lookup_info is None:
return AnyType(TypeOfAny.explicit)
for lookup_base in helpers.iter_bases(lookup_info):
if lookup_base.args and isinstance(lookup_base.args[0], Instance):
lookup_type: MypyType = lookup_base.args[0]
# if it's Field, consider lookup_type a __get__ of current field
if (isinstance(lookup_type, Instance)
and lookup_type.type.fullname()
== fullnames.FIELD_FULLNAME):
field_info = helpers.lookup_class_typeinfo(
helpers.get_typechecker_api(ctx), field.__class__)
if field_info is None:
return AnyType(TypeOfAny.explicit)
lookup_type = helpers.get_private_descriptor_type(
field_info,
'_pyi_private_get_type',
is_nullable=field.null)
return lookup_type
return AnyType(TypeOfAny.explicit)
