cpython/Lib/imp.py

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"""This module provides the components needed to build your own __import__
function. Undocumented functions are obsolete.
In most cases it is preferred you consider using the importlib module's
functionality over this module.
"""
# (Probably) need to stay in _imp
from _imp import (lock_held, acquire_lock, release_lock,
get_frozen_object, is_frozen_package,
init_builtin, init_frozen, is_builtin, is_frozen,
_fix_co_filename)
try:
from _imp import load_dynamic
except ImportError:
# Platform doesn't support dynamic loading.
load_dynamic = None
from importlib._bootstrap import SourcelessFileLoader, _ERR_MSG
from importlib import machinery
from importlib import util
import importlib
import os
import sys
import tokenize
import types
import warnings
warnings.warn("the imp module is deprecated in favour of importlib; "
"see the module's documentation for alternative uses",
PendingDeprecationWarning)
# DEPRECATED
SEARCH_ERROR = 0
PY_SOURCE = 1
PY_COMPILED = 2
C_EXTENSION = 3
PY_RESOURCE = 4
PKG_DIRECTORY = 5
C_BUILTIN = 6
PY_FROZEN = 7
PY_CODERESOURCE = 8
IMP_HOOK = 9
def new_module(name):
"""**DEPRECATED**
Create a new module.
The module is not entered into sys.modules.
"""
return types.ModuleType(name)
def get_magic():
"""**DEPRECATED**
Return the magic number for .pyc or .pyo files.
"""
return util.MAGIC_NUMBER
def get_tag():
"""Return the magic tag for .pyc or .pyo files."""
return sys.implementation.cache_tag
def cache_from_source(path, debug_override=None):
"""**DEPRECATED**
Given the path to a .py file, return the path to its .pyc/.pyo file.
The .py file does not need to exist; this simply returns the path to the
.pyc/.pyo file calculated as if the .py file were imported. The extension
will be .pyc unless sys.flags.optimize is non-zero, then it will be .pyo.
If debug_override is not None, then it must be a boolean and is used in
place of sys.flags.optimize.
If sys.implementation.cache_tag is None then NotImplementedError is raised.
"""
return util.cache_from_source(path, debug_override)
def source_from_cache(path):
"""**DEPRECATED**
Given the path to a .pyc./.pyo file, return the path to its .py file.
The .pyc/.pyo file does not need to exist; this simply returns the path to
the .py file calculated to correspond to the .pyc/.pyo file. If path does
not conform to PEP 3147 format, ValueError will be raised. If
sys.implementation.cache_tag is None then NotImplementedError is raised.
"""
return util.source_from_cache(path)
def get_suffixes():
"""**DEPRECATED**"""
extensions = [(s, 'rb', C_EXTENSION) for s in machinery.EXTENSION_SUFFIXES]
source = [(s, 'U', PY_SOURCE) for s in machinery.SOURCE_SUFFIXES]
bytecode = [(s, 'rb', PY_COMPILED) for s in machinery.BYTECODE_SUFFIXES]
return extensions + source + bytecode
class NullImporter:
"""**DEPRECATED**
Null import object.
"""
def __init__(self, path):
if path == '':
raise ImportError('empty pathname', path='')
elif os.path.isdir(path):
raise ImportError('existing directory', path=path)
def find_module(self, fullname):
"""Always returns None."""
return None
class _HackedGetData:
"""Compatibiilty support for 'file' arguments of various load_*()
functions."""
def __init__(self, fullname, path, file=None):
super().__init__(fullname, path)
self.file = file
def get_data(self, path):
"""Gross hack to contort loader to deal w/ load_*()'s bad API."""
if self.file and path == self.path:
with self.file:
# Technically should be returning bytes, but
# SourceLoader.get_code() just passed what is returned to
# compile() which can handle str. And converting to bytes would
# require figuring out the encoding to decode to and
# tokenize.detect_encoding() only accepts bytes.
return self.file.read()
else:
return super().get_data(path)
class _LoadSourceCompatibility(_HackedGetData, machinery.SourceFileLoader):
"""Compatibility support for implementing load_source()."""
def load_source(name, pathname, file=None):
_LoadSourceCompatibility(name, pathname, file).load_module(name)
module = sys.modules[name]
# To allow reloading to potentially work, use a non-hacked loader which
# won't rely on a now-closed file object.
module.__loader__ = machinery.SourceFileLoader(name, pathname)
return module
class _LoadCompiledCompatibility(_HackedGetData, SourcelessFileLoader):
"""Compatibility support for implementing load_compiled()."""
def load_compiled(name, pathname, file=None):
"""**DEPRECATED**"""
_LoadCompiledCompatibility(name, pathname, file).load_module(name)
module = sys.modules[name]
# To allow reloading to potentially work, use a non-hacked loader which
# won't rely on a now-closed file object.
module.__loader__ = SourcelessFileLoader(name, pathname)
return module
def load_package(name, path):
"""**DEPRECATED**"""
if os.path.isdir(path):
extensions = (machinery.SOURCE_SUFFIXES[:] +
machinery.BYTECODE_SUFFIXES[:])
for extension in extensions:
path = os.path.join(path, '__init__'+extension)
if os.path.exists(path):
break
else:
raise ValueError('{!r} is not a package'.format(path))
return machinery.SourceFileLoader(name, path).load_module(name)
def load_module(name, file, filename, details):
"""**DEPRECATED**
Load a module, given information returned by find_module().
The module name must include the full package name, if any.
"""
suffix, mode, type_ = details
if mode and (not mode.startswith(('r', 'U')) or '+' in mode):
raise ValueError('invalid file open mode {!r}'.format(mode))
elif file is None and type_ in {PY_SOURCE, PY_COMPILED}:
msg = 'file object required for import (type code {})'.format(type_)
raise ValueError(msg)
elif type_ == PY_SOURCE:
return load_source(name, filename, file)
elif type_ == PY_COMPILED:
return load_compiled(name, filename, file)
elif type_ == C_EXTENSION and load_dynamic is not None:
if file is None:
with open(filename, 'rb') as opened_file:
return load_dynamic(name, filename, opened_file)
else:
return load_dynamic(name, filename, file)
elif type_ == PKG_DIRECTORY:
return load_package(name, filename)
elif type_ == C_BUILTIN:
return init_builtin(name)
elif type_ == PY_FROZEN:
return init_frozen(name)
else:
msg = "Don't know how to import {} (type code {})".format(name, type_)
raise ImportError(msg, name=name)
def find_module(name, path=None):
"""**DEPRECATED**
Search for a module.
If path is omitted or None, search for a built-in, frozen or special
module and continue search in sys.path. The module name cannot
contain '.'; to search for a submodule of a package, pass the
submodule name and the package's __path__.
"""
if not isinstance(name, str):
raise TypeError("'name' must be a str, not {}".format(type(name)))
elif not isinstance(path, (type(None), list)):
# Backwards-compatibility
raise RuntimeError("'list' must be None or a list, "
"not {}".format(type(name)))
if path is None:
if is_builtin(name):
return None, None, ('', '', C_BUILTIN)
elif is_frozen(name):
return None, None, ('', '', PY_FROZEN)
else:
path = sys.path
for entry in path:
package_directory = os.path.join(entry, name)
for suffix in ['.py', machinery.BYTECODE_SUFFIXES[0]]:
package_file_name = '__init__' + suffix
file_path = os.path.join(package_directory, package_file_name)
if os.path.isfile(file_path):
return None, package_directory, ('', '', PKG_DIRECTORY)
for suffix, mode, type_ in get_suffixes():
file_name = name + suffix
file_path = os.path.join(entry, file_name)
if os.path.isfile(file_path):
break
else:
continue
break # Break out of outer loop when breaking out of inner loop.
else:
raise ImportError(_ERR_MSG.format(name), name=name)
encoding = None
if mode == 'U':
with open(file_path, 'rb') as file:
encoding = tokenize.detect_encoding(file.readline)[0]
file = open(file_path, mode, encoding=encoding)
return file, file_path, (suffix, mode, type_)
def reload(module):
"""**DEPRECATED**
Reload the module and return it.
The module must have been successfully imported before.
"""
return importlib.reload(module)