| from mypy.plugin import Plugin | |
| from mypy.nodes import ( | |
| ClassDef, Block, TypeInfo, SymbolTable, SymbolTableNode, MDEF, GDEF, Var | |
| ) | |
| class DynPlugin(Plugin): | |
| def get_dynamic_class_hook(self, fullname): | |
| if fullname == 'lib.declarative_base': | |
| return add_info_hook | |
| return None | |
| def get_base_class_hook(self, fullname: str): | |
| sym = self.lookup_fully_qualified(fullname) | |
| if sym and isinstance(sym.node, TypeInfo): | |
| if sym.node.metadata.get('magic'): | |
| return add_magic_hook | |
| return None | |
| def add_info_hook(ctx) -> None: | |
| class_def = ClassDef(ctx.name, Block([])) | |
| class_def.fullname = ctx.api.qualified_name(ctx.name) | |
| info = TypeInfo(SymbolTable(), class_def, ctx.api.cur_mod_id) | |
| class_def.info = info | |
| obj = ctx.api.named_type('builtins.object') | |
| info.mro = [info, obj.type] | |
| info.bases = [obj] | |
| ctx.api.add_symbol_table_node(ctx.name, SymbolTableNode(GDEF, info)) | |
| info.metadata['magic'] = True | |
| def add_magic_hook(ctx) -> None: | |
| info = ctx.cls.info | |
| str_type = ctx.api.named_type_or_none('builtins.str', []) | |
| assert str_type is not None | |
| var = Var('__magic__', str_type) | |
| var.info = info | |
| info.names['__magic__'] = SymbolTableNode(MDEF, var) | |
| def plugin(version): | |
| return DynPlugin |