Source code
Revision control
Copy as Markdown
Other Tools
from __future__ import absolute_import, unicode_literals
import io
import abc
import sys
import email
if sys.version_info > (3,): # pragma: nocover
import builtins
from configparser import ConfigParser
import contextlib
FileNotFoundError = builtins.FileNotFoundError
IsADirectoryError = builtins.IsADirectoryError
NotADirectoryError = builtins.NotADirectoryError
PermissionError = builtins.PermissionError
map = builtins.map
from itertools import filterfalse
else: # pragma: nocover
from backports.configparser import ConfigParser
from itertools import imap as map # type: ignore
from itertools import ifilterfalse as filterfalse
import contextlib2 as contextlib
FileNotFoundError = IOError, OSError
IsADirectoryError = IOError, OSError
NotADirectoryError = IOError, OSError
PermissionError = IOError, OSError
str = type('')
suppress = contextlib.suppress
if sys.version_info > (3, 5): # pragma: nocover
import pathlib
else: # pragma: nocover
import pathlib2 as pathlib
try:
ModuleNotFoundError = builtins.FileNotFoundError
except (NameError, AttributeError): # pragma: nocover
ModuleNotFoundError = ImportError # type: ignore
if sys.version_info >= (3,): # pragma: nocover
from importlib.abc import MetaPathFinder
else: # pragma: nocover
class MetaPathFinder(object):
__metaclass__ = abc.ABCMeta
__metaclass__ = type
__all__ = [
'install', 'NullFinder', 'MetaPathFinder', 'ModuleNotFoundError',
'pathlib', 'ConfigParser', 'map', 'suppress', 'FileNotFoundError',
'NotADirectoryError', 'email_message_from_string',
]
def install(cls):
"""
Class decorator for installation on sys.meta_path.
Adds the backport DistributionFinder to sys.meta_path and
attempts to disable the finder functionality of the stdlib
DistributionFinder.
"""
sys.meta_path.append(cls())
disable_stdlib_finder()
return cls
def disable_stdlib_finder():
"""
Give the backport primacy for discovering path-based distributions
by monkey-patching the stdlib O_O.
See #91 for more background for rationale on this sketchy
behavior.
"""
def matches(finder):
return (
getattr(finder, '__module__', None) == '_frozen_importlib_external'
and hasattr(finder, 'find_distributions')
)
for finder in filter(matches, sys.meta_path): # pragma: nocover
del finder.find_distributions
class NullFinder:
"""
A "Finder" (aka "MetaClassFinder") that never finds any modules,
but may find distributions.
"""
@staticmethod
def find_spec(*args, **kwargs):
return None
# In Python 2, the import system requires finders
# to have a find_module() method, but this usage
# is deprecated in Python 3 in favor of find_spec().
# For the purposes of this finder (i.e. being present
# on sys.meta_path but having no other import
# system functionality), the two methods are identical.
find_module = find_spec
def py2_message_from_string(text): # nocoverpy3
# email.message_from_string cannot handle Unicode on Python 2.
io_buffer = io.StringIO(text)
return email.message_from_file(io_buffer)
email_message_from_string = (
py2_message_from_string
if sys.version_info < (3,) else
email.message_from_string
)
class PyPy_repr:
"""
Override repr for EntryPoint objects on PyPy to avoid __iter__ access.
Ref #97, #102.
"""
affected = hasattr(sys, 'pypy_version_info')
def __compat_repr__(self): # pragma: nocover
def make_param(name):
value = getattr(self, name)
return '{name}={value!r}'.format(**locals())
params = ', '.join(map(make_param, self._fields))
return 'EntryPoint({params})'.format(**locals())
if affected: # pragma: nocover
__repr__ = __compat_repr__
del affected
# from itertools recipes
def unique_everseen(iterable): # pragma: nocover
"List unique elements, preserving order. Remember all elements ever seen."
seen = set()
seen_add = seen.add
for element in filterfalse(seen.__contains__, iterable):
seen_add(element)
yield element
unique_ordered = (
unique_everseen if sys.version_info < (3, 7) else dict.fromkeys)