def _add_finder(importer, finder):
"""Register a new pkg_resources path finder that does not replace the existing finder."""
existing_finder = _get_finder(importer)
if not existing_finder:
pkg_resources.register_finder(importer, finder)
else:
pkg_resources.register_finder(importer, ChainedFinder.of(existing_finder, finder))
def _add_finder(importer, finder):
"""Register a new pkg_resources path finder that does not replace the existing finder."""
existing_finder = _get_finder(importer)
if not existing_finder:
pkg_resources.register_finder(importer, finder)
else:
pkg_resources.register_finder(
importer, ChainedFinder.of(existing_finder, finder))
def unregister_finders():
"""Unregister finders necessary for PEX to function properly."""
global __PREVIOUS_FINDER
if not __PREVIOUS_FINDER:
return
pkg_resources.register_finder(zipimport.zipimporter, __PREVIOUS_FINDER)
_remove_finder(pkgutil.ImpImporter, find_wheels_on_path)
if importlib_machinery is not None:
_remove_finder(importlib_machinery.FileFinder, find_wheels_on_path)
__PREVIOUS_FINDER = None
def unregister_finders():
"""Unregister finders necessary for PEX to function properly."""
global __PREVIOUS_FINDER
if not __PREVIOUS_FINDER:
return
pkg_resources.register_finder(zipimport.zipimporter, __PREVIOUS_FINDER)
_remove_finder(pkgutil.ImpImporter, find_wheels_on_path)
if importlib_machinery is not None:
_remove_finder(importlib_machinery.FileFinder, find_wheels_on_path)
__PREVIOUS_FINDER = None
def register_finders():
"""Register finders necessary for PEX to function properly."""
# If the previous finder is set, then we've already monkeypatched, so skip.
global __PREVIOUS_FINDER
if __PREVIOUS_FINDER:
return
# save previous finder so that it can be restored
previous_finder = _get_finder(zipimport.zipimporter)
assert previous_finder, 'This appears to be using an incompatible setuptools.'
# Enable finding zipped wheels.
pkg_resources.register_finder(
zipimport.zipimporter, ChainedFinder.of(pkg_resources.find_eggs_in_zip, find_wheels_in_zip))
# append the wheel finder
_add_finder(pkgutil.ImpImporter, find_wheels_on_path)
if importlib_machinery is not None:
_add_finder(importlib_machinery.FileFinder, find_wheels_on_path)
__PREVIOUS_FINDER = previous_finder
def register_finders():
"""Register finders necessary for PEX to function properly."""
# If the previous finder is set, then we've already monkeypatched, so skip.
global __PREVIOUS_FINDER
if __PREVIOUS_FINDER:
return
# save previous finder so that it can be restored
previous_finder = _get_finder(zipimport.zipimporter)
assert previous_finder, 'This appears to be using an incompatible setuptools.'
# Enable finding zipped wheels.
pkg_resources.register_finder(
zipimport.zipimporter,
ChainedFinder.of(pkg_resources.find_eggs_in_zip, find_wheels_in_zip))
# append the wheel finder
_add_finder(pkgutil.ImpImporter, find_wheels_on_path)
if importlib_machinery is not None:
_add_finder(importlib_machinery.FileFinder, find_wheels_on_path)
__PREVIOUS_FINDER = previous_finder
def _remove_finder(importer, finder):
"""Remove an existing finder from pkg_resources."""
existing_finder = _get_finder(importer)
if not existing_finder:
return
if isinstance(existing_finder, ChainedFinder):
try:
existing_finder.finders.remove(finder)
except ValueError:
return
if len(existing_finder.finders) == 1:
pkg_resources.register_finder(importer, existing_finder.finders[0])
elif len(existing_finder.finders) == 0:
pkg_resources.register_finder(importer, pkg_resources.find_nothing)
else:
pkg_resources.register_finder(importer, pkg_resources.find_nothing)
def _remove_finder(importer, finder):
"""Remove an existing finder from pkg_resources."""
existing_finder = _get_finder(importer)
if not existing_finder:
return
if isinstance(existing_finder, ChainedFinder):
try:
existing_finder.finders.remove(finder)
except ValueError:
return
if len(existing_finder.finders) == 1:
pkg_resources.register_finder(importer, existing_finder.finders[0])
elif len(existing_finder.finders) == 0:
pkg_resources.register_finder(importer, pkg_resources.find_nothing)
else:
pkg_resources.register_finder(importer, pkg_resources.find_nothing)