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authornkozlovskiy <nmk@ydb.tech>2023-09-29 12:24:06 +0300
committernkozlovskiy <nmk@ydb.tech>2023-09-29 12:41:34 +0300
commite0e3e1717e3d33762ce61950504f9637a6e669ed (patch)
treebca3ff6939b10ed60c3d5c12439963a1146b9711 /contrib/tools/python3/src/Lib/importlib/util.py
parent38f2c5852db84c7b4d83adfcb009eb61541d1ccd (diff)
downloadydb-e0e3e1717e3d33762ce61950504f9637a6e669ed.tar.gz
add ydb deps
Diffstat (limited to 'contrib/tools/python3/src/Lib/importlib/util.py')
-rw-r--r--contrib/tools/python3/src/Lib/importlib/util.py302
1 files changed, 302 insertions, 0 deletions
diff --git a/contrib/tools/python3/src/Lib/importlib/util.py b/contrib/tools/python3/src/Lib/importlib/util.py
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+"""Utility code for constructing importers, etc."""
+from ._abc import Loader
+from ._bootstrap import module_from_spec
+from ._bootstrap import _resolve_name
+from ._bootstrap import spec_from_loader
+from ._bootstrap import _find_spec
+from ._bootstrap_external import MAGIC_NUMBER
+from ._bootstrap_external import _RAW_MAGIC_NUMBER
+from ._bootstrap_external import cache_from_source
+from ._bootstrap_external import decode_source
+from ._bootstrap_external import source_from_cache
+from ._bootstrap_external import spec_from_file_location
+
+from contextlib import contextmanager
+import _imp
+import functools
+import sys
+import types
+import warnings
+
+
+def source_hash(source_bytes):
+ "Return the hash of *source_bytes* as used in hash-based pyc files."
+ return _imp.source_hash(_RAW_MAGIC_NUMBER, source_bytes)
+
+
+def resolve_name(name, package):
+ """Resolve a relative module name to an absolute one."""
+ if not name.startswith('.'):
+ return name
+ elif not package:
+ raise ImportError(f'no package specified for {repr(name)} '
+ '(required for relative module names)')
+ level = 0
+ for character in name:
+ if character != '.':
+ break
+ level += 1
+ return _resolve_name(name[level:], package, level)
+
+
+def _find_spec_from_path(name, path=None):
+ """Return the spec for the specified module.
+
+ First, sys.modules is checked to see if the module was already imported. If
+ so, then sys.modules[name].__spec__ is returned. If that happens to be
+ set to None, then ValueError is raised. If the module is not in
+ sys.modules, then sys.meta_path is searched for a suitable spec with the
+ value of 'path' given to the finders. None is returned if no spec could
+ be found.
+
+ Dotted names do not have their parent packages implicitly imported. You will
+ most likely need to explicitly import all parent packages in the proper
+ order for a submodule to get the correct spec.
+
+ """
+ if name not in sys.modules:
+ return _find_spec(name, path)
+ else:
+ module = sys.modules[name]
+ if module is None:
+ return None
+ try:
+ spec = module.__spec__
+ except AttributeError:
+ raise ValueError('{}.__spec__ is not set'.format(name)) from None
+ else:
+ if spec is None:
+ raise ValueError('{}.__spec__ is None'.format(name))
+ return spec
+
+
+def find_spec(name, package=None):
+ """Return the spec for the specified module.
+
+ First, sys.modules is checked to see if the module was already imported. If
+ so, then sys.modules[name].__spec__ is returned. If that happens to be
+ set to None, then ValueError is raised. If the module is not in
+ sys.modules, then sys.meta_path is searched for a suitable spec with the
+ value of 'path' given to the finders. None is returned if no spec could
+ be found.
+
+ If the name is for submodule (contains a dot), the parent module is
+ automatically imported.
+
+ The name and package arguments work the same as importlib.import_module().
+ In other words, relative module names (with leading dots) work.
+
+ """
+ fullname = resolve_name(name, package) if name.startswith('.') else name
+ if fullname not in sys.modules:
+ parent_name = fullname.rpartition('.')[0]
+ if parent_name:
+ parent = __import__(parent_name, fromlist=['__path__'])
+ try:
+ parent_path = parent.__path__
+ except AttributeError as e:
+ raise ModuleNotFoundError(
+ f"__path__ attribute not found on {parent_name!r} "
+ f"while trying to find {fullname!r}", name=fullname) from e
+ else:
+ parent_path = None
+ return _find_spec(fullname, parent_path)
+ else:
+ module = sys.modules[fullname]
+ if module is None:
+ return None
+ try:
+ spec = module.__spec__
+ except AttributeError:
+ raise ValueError('{}.__spec__ is not set'.format(name)) from None
+ else:
+ if spec is None:
+ raise ValueError('{}.__spec__ is None'.format(name))
+ return spec
+
+
+@contextmanager
+def _module_to_load(name):
+ is_reload = name in sys.modules
+
+ module = sys.modules.get(name)
+ if not is_reload:
+ # This must be done before open() is called as the 'io' module
+ # implicitly imports 'locale' and would otherwise trigger an
+ # infinite loop.
+ module = type(sys)(name)
+ # This must be done before putting the module in sys.modules
+ # (otherwise an optimization shortcut in import.c becomes wrong)
+ module.__initializing__ = True
+ sys.modules[name] = module
+ try:
+ yield module
+ except Exception:
+ if not is_reload:
+ try:
+ del sys.modules[name]
+ except KeyError:
+ pass
+ finally:
+ module.__initializing__ = False
+
+
+def set_package(fxn):
+ """Set __package__ on the returned module.
+
+ This function is deprecated.
+
+ """
+ @functools.wraps(fxn)
+ def set_package_wrapper(*args, **kwargs):
+ warnings.warn('The import system now takes care of this automatically; '
+ 'this decorator is slated for removal in Python 3.12',
+ DeprecationWarning, stacklevel=2)
+ module = fxn(*args, **kwargs)
+ if getattr(module, '__package__', None) is None:
+ module.__package__ = module.__name__
+ if not hasattr(module, '__path__'):
+ module.__package__ = module.__package__.rpartition('.')[0]
+ return module
+ return set_package_wrapper
+
+
+def set_loader(fxn):
+ """Set __loader__ on the returned module.
+
+ This function is deprecated.
+
+ """
+ @functools.wraps(fxn)
+ def set_loader_wrapper(self, *args, **kwargs):
+ warnings.warn('The import system now takes care of this automatically; '
+ 'this decorator is slated for removal in Python 3.12',
+ DeprecationWarning, stacklevel=2)
+ module = fxn(self, *args, **kwargs)
+ if getattr(module, '__loader__', None) is None:
+ module.__loader__ = self
+ return module
+ return set_loader_wrapper
+
+
+def module_for_loader(fxn):
+ """Decorator to handle selecting the proper module for loaders.
+
+ The decorated function is passed the module to use instead of the module
+ name. The module passed in to the function is either from sys.modules if
+ it already exists or is a new module. If the module is new, then __name__
+ is set the first argument to the method, __loader__ is set to self, and
+ __package__ is set accordingly (if self.is_package() is defined) will be set
+ before it is passed to the decorated function (if self.is_package() does
+ not work for the module it will be set post-load).
+
+ If an exception is raised and the decorator created the module it is
+ subsequently removed from sys.modules.
+
+ The decorator assumes that the decorated function takes the module name as
+ the second argument.
+
+ """
+ warnings.warn('The import system now takes care of this automatically; '
+ 'this decorator is slated for removal in Python 3.12',
+ DeprecationWarning, stacklevel=2)
+ @functools.wraps(fxn)
+ def module_for_loader_wrapper(self, fullname, *args, **kwargs):
+ with _module_to_load(fullname) as module:
+ module.__loader__ = self
+ try:
+ is_package = self.is_package(fullname)
+ except (ImportError, AttributeError):
+ pass
+ else:
+ if is_package:
+ module.__package__ = fullname
+ else:
+ module.__package__ = fullname.rpartition('.')[0]
+ # If __package__ was not set above, __import__() will do it later.
+ return fxn(self, module, *args, **kwargs)
+
+ return module_for_loader_wrapper
+
+
+class _LazyModule(types.ModuleType):
+
+ """A subclass of the module type which triggers loading upon attribute access."""
+
+ def __getattribute__(self, attr):
+ """Trigger the load of the module and return the attribute."""
+ # All module metadata must be garnered from __spec__ in order to avoid
+ # using mutated values.
+ # Stop triggering this method.
+ self.__class__ = types.ModuleType
+ # Get the original name to make sure no object substitution occurred
+ # in sys.modules.
+ original_name = self.__spec__.name
+ # Figure out exactly what attributes were mutated between the creation
+ # of the module and now.
+ attrs_then = self.__spec__.loader_state['__dict__']
+ attrs_now = self.__dict__
+ attrs_updated = {}
+ for key, value in attrs_now.items():
+ # Code that set the attribute may have kept a reference to the
+ # assigned object, making identity more important than equality.
+ if key not in attrs_then:
+ attrs_updated[key] = value
+ elif id(attrs_now[key]) != id(attrs_then[key]):
+ attrs_updated[key] = value
+ self.__spec__.loader.exec_module(self)
+ # If exec_module() was used directly there is no guarantee the module
+ # object was put into sys.modules.
+ if original_name in sys.modules:
+ if id(self) != id(sys.modules[original_name]):
+ raise ValueError(f"module object for {original_name!r} "
+ "substituted in sys.modules during a lazy "
+ "load")
+ # Update after loading since that's what would happen in an eager
+ # loading situation.
+ self.__dict__.update(attrs_updated)
+ return getattr(self, attr)
+
+ def __delattr__(self, attr):
+ """Trigger the load and then perform the deletion."""
+ # To trigger the load and raise an exception if the attribute
+ # doesn't exist.
+ self.__getattribute__(attr)
+ delattr(self, attr)
+
+
+class LazyLoader(Loader):
+
+ """A loader that creates a module which defers loading until attribute access."""
+
+ @staticmethod
+ def __check_eager_loader(loader):
+ if not hasattr(loader, 'exec_module'):
+ raise TypeError('loader must define exec_module()')
+
+ @classmethod
+ def factory(cls, loader):
+ """Construct a callable which returns the eager loader made lazy."""
+ cls.__check_eager_loader(loader)
+ return lambda *args, **kwargs: cls(loader(*args, **kwargs))
+
+ def __init__(self, loader):
+ self.__check_eager_loader(loader)
+ self.loader = loader
+
+ def create_module(self, spec):
+ return self.loader.create_module(spec)
+
+ def exec_module(self, module):
+ """Make the module load lazily."""
+ module.__spec__.loader = self.loader
+ module.__loader__ = self.loader
+ # Don't need to worry about deep-copying as trying to set an attribute
+ # on an object would have triggered the load,
+ # e.g. ``module.__spec__.loader = None`` would trigger a load from
+ # trying to access module.__spec__.
+ loader_state = {}
+ loader_state['__dict__'] = module.__dict__.copy()
+ loader_state['__class__'] = module.__class__
+ module.__spec__.loader_state = loader_state
+ module.__class__ = _LazyModule