def apply_interface(
iface_arg: Expression,
class_info: TypeInfo,
api: SemanticAnalyzerPluginInterface,
context: Context,
) -> None:
if not isinstance(iface_arg, RefExpr):
api.fail("Argument to implementer should be a ref expression",
iface_arg)
return
iface_name = iface_arg.fullname
if iface_name is None:
# unknown interface, probably from stubless package
return
iface_type = iface_arg.node
if iface_type is None:
return
if not isinstance(iface_type, TypeInfo):
# Possibly an interface from unimported package, ignore
return
if not self._is_interface(iface_type):
api.fail(
f"zope.interface.implementer accepts interface, "
f"not {iface_name}.",
iface_arg,
)
api.fail(
f"Make sure you have stubs for all packages that "
f"provide interfaces for {iface_name} class hierarchy.",
iface_arg,
)
return
# print("CLASS INFO", class_info)
md = self._get_metadata(class_info)
if "implements" not in md:
md["implements"] = []
# impl_list = cast(List[str], md['implements'])
md["implements"].append(iface_type.fullname)
self.log(f"Found implementation of "
f"{iface_type.fullname}: {class_info.fullname}")
# Make sure implementation is treated as a subtype of an interface. Pretend
# there is a decorator for the class that will create a "type promotion",
# but ensure this only gets applied a single time per interface.
promote = Instance(iface_type, [])
if not any(ti._promote == promote for ti in class_info.mro):
faketi = TypeInfo(SymbolTable(), iface_type.defn,
iface_type.module_name)
faketi._promote = promote
class_info.mro.append(faketi)
def _apply_interface(self, impl: TypeInfo, iface: TypeInfo) -> None:
md = self._get_metadata(impl)
if "implements" not in md:
md["implements"] = []
md["implements"].append(iface.fullname)
self.log(f"Found implementation of "
f"{iface.fullname}: {impl.fullname}")
# Make sure implementation is treated as a subtype of an interface. Pretend
# there is a decorator for the class that will create a "type promotion",
# but ensure this only gets applied a single time per interface.
promote = Instance(iface, [])
if not any(ti._promote == promote for ti in impl.mro):
faketi = TypeInfo(SymbolTable(), iface.defn, iface.module_name)
faketi._promote = promote
impl.mro.append(faketi)
