[ PARENT ]

EDIT :: langhelpers.py

from __future__ import annotations import collections from collections.abc import Iterable import textwrap from typing import Any from typing import Callable from typing import Dict from typing import List from typing import Mapping from typing import Optional from typing import overload from typing import Sequence from typing import Tuple from typing import TypeVar from typing import Union import uuid import warnings from sqlalchemy.util import asbool # noqa from sqlalchemy.util import immutabledict # noqa from sqlalchemy.util import memoized_property # noqa from sqlalchemy.util import to_list # noqa from sqlalchemy.util import unique_list # noqa from .compat import inspect_getfullargspec EMPTY_DICT: Mapping[Any, Any] = immutabledict() _T = TypeVar("_T") class _ModuleClsMeta(type): def __setattr__(cls, key: str, value: Callable) -> None: super().__setattr__(key, value) cls._update_module_proxies(key) # type: ignore class ModuleClsProxy(metaclass=_ModuleClsMeta): """Create module level proxy functions for the methods on a given class. The functions will have a compatible signature as the methods. """ _setups: Dict[type, Tuple[set, list]] = collections.defaultdict( lambda: (set(), []) ) @classmethod def _update_module_proxies(cls, name: str) -> None: attr_names, modules = cls._setups[cls] for globals_, locals_ in modules: cls._add_proxied_attribute(name, globals_, locals_, attr_names) def _install_proxy(self) -> None: attr_names, modules = self._setups[self.__class__] for globals_, locals_ in modules: globals_["_proxy"] = self for attr_name in attr_names: globals_[attr_name] = getattr(self, attr_name) def _remove_proxy(self) -> None: attr_names, modules = self._setups[self.__class__] for globals_, locals_ in modules: globals_["_proxy"] = None for attr_name in attr_names: del globals_[attr_name] @classmethod def create_module_class_proxy(cls, globals_, locals_): attr_names, modules = cls._setups[cls] modules.append((globals_, locals_)) cls._setup_proxy(globals_, locals_, attr_names) @classmethod def _setup_proxy(cls, globals_, locals_, attr_names): for methname in dir(cls): cls._add_proxied_attribute(methname, globals_, locals_, attr_names) @classmethod def _add_proxied_attribute(cls, methname, globals_, locals_, attr_names): if not methname.startswith("_"): meth = getattr(cls, methname) if callable(meth): locals_[methname] = cls._create_method_proxy( methname, globals_, locals_ ) else: attr_names.add(methname) @classmethod def _create_method_proxy(cls, name, globals_, locals_): fn = getattr(cls, name) def _name_error(name, from_): raise NameError( "Can't invoke function '%s', as the proxy object has " "not yet been " "established for the Alembic '%s' class. " "Try placing this code inside a callable." % (name, cls.__name__) ) from from_ globals_["_name_error"] = _name_error translations = getattr(fn, "_legacy_translations", []) if translations: spec = inspect_getfullargspec(fn) if spec[0] and spec[0][0] == "self": spec[0].pop(0) outer_args = inner_args = "*args, **kw" translate_str = "args, kw = _translate(%r, %r, %r, args, kw)" % ( fn.__name__, tuple(spec), translations, ) def translate(fn_name, spec, translations, args, kw): return_kw = {} return_args = [] for oldname, newname in translations: if oldname in kw: warnings.warn( "Argument %r is now named %r " "for method %s()." % (oldname, newname, fn_name) ) return_kw[newname] = kw.pop(oldname) return_kw.update(kw) args = list(args) if spec[3]: pos_only = spec[0][: -len(spec[3])] else: pos_only = spec[0] for arg in pos_only: if arg not in return_kw: try: return_args.append(args.pop(0)) except IndexError: raise TypeError( "missing required positional argument: %s" % arg ) return_args.extend(args) return return_args, return_kw globals_["_translate"] = translate else: outer_args = "*args, **kw" inner_args = "*args, **kw" translate_str = "" func_text = textwrap.dedent( """\ def %(name)s(%(args)s): %(doc)r %(translate)s try: p = _proxy except NameError as ne: _name_error('%(name)s', ne) return _proxy.%(name)s(%(apply_kw)s) e """ % { "name": name, "translate": translate_str, "args": outer_args, "apply_kw": inner_args, "doc": fn.__doc__, } ) lcl = {} exec(func_text, globals_, lcl) return lcl[name] def _with_legacy_names(translations): def decorate(fn): fn._legacy_translations = translations return fn return decorate def rev_id() -> str: return uuid.uuid4().hex[-12:] @overload def to_tuple(x: Any, default: tuple) -> tuple: ... @overload def to_tuple(x: None, default: Optional[_T] = None) -> _T: ... @overload def to_tuple(x: Any, default: Optional[tuple] = None) -> tuple: ... def to_tuple(x, default=None): if x is None: return default elif isinstance(x, str): return (x,) elif isinstance(x, Iterable): return tuple(x) else: return (x,) def dedupe_tuple(tup: Tuple[str, ...]) -> Tuple[str, ...]: return tuple(unique_list(tup)) class Dispatcher: def __init__(self, uselist: bool = False) -> None: self._registry: Dict[tuple, Any] = {} self.uselist = uselist def dispatch_for( self, target: Any, qualifier: str = "default" ) -> Callable: def decorate(fn): if self.uselist: self._registry.setdefault((target, qualifier), []).append(fn) else: assert (target, qualifier) not in self._registry self._registry[(target, qualifier)] = fn return fn return decorate def dispatch(self, obj: Any, qualifier: str = "default") -> Any: if isinstance(obj, str): targets: Sequence = [obj] elif isinstance(obj, type): targets = obj.__mro__ else: targets = type(obj).__mro__ for spcls in targets: if qualifier != "default" and (spcls, qualifier) in self._registry: return self._fn_or_list(self._registry[(spcls, qualifier)]) elif (spcls, "default") in self._registry: return self._fn_or_list(self._registry[(spcls, "default")]) else: raise ValueError("no dispatch function for object: %s" % obj) def _fn_or_list( self, fn_or_list: Union[List[Callable], Callable] ) -> Callable: if self.uselist: def go(*arg, **kw): for fn in fn_or_list: fn(*arg, **kw) return go else: return fn_or_list # type: ignore def branch(self) -> Dispatcher: """Return a copy of this dispatcher that is independently writable.""" d = Dispatcher() if self.uselist: d._registry.update( (k, [fn for fn in self._registry[k]]) for k in self._registry ) else: d._registry.update(self._registry) return d def not_none(value: Optional[_T]) -> _T: assert value is not None return value

SAVE CANCEL