def get_rosdirectoryfinder_index_in_path_hooks():
return sys.path_hooks.index(ros_path_hook)
python类path_hooks()的实例源码
def deactivate():
# CAREFUL : Even though we remove the path from sys.path,
# initialized finders will remain in sys.path_importer_cache
# removing metahook
sys.meta_path.pop(get_rospathfinder_index_in_meta_hooks())
# removing path_hook
sys.path_hooks.pop(get_rosdirectoryfinder_index_in_path_hooks())
filefinder2.deactivate()
# Resetting sys.path_importer_cache to get rid of previous importers
sys.path_importer_cache.clear()
def _get_importer(path_name):
"""Python version of PyImport_GetImporter C API function"""
cache = sys.path_importer_cache
try:
importer = cache[path_name]
except KeyError:
# Not yet cached. Flag as using the
# standard machinery until we finish
# checking the hooks
cache[path_name] = None
for hook in sys.path_hooks:
try:
importer = hook(path_name)
break
except ImportError:
pass
else:
# The following check looks a bit odd. The trick is that
# NullImporter throws ImportError if the supplied path is a
# *valid* directory entry (and hence able to be handled
# by the standard import machinery)
try:
importer = imp.NullImporter(path_name)
except ImportError:
return None
cache[path_name] = importer
return importer
def test_path_hooks(self):
# Test that sys.path_hooks is used.
# Test that sys.path_importer_cache is set.
module = '<test module>'
path = '<test path>'
importer = util.mock_modules(module)
hook = import_util.mock_path_hook(path, importer=importer)
with util.import_state(path_hooks=[hook]):
loader = machinery.PathFinder.find_module(module, [path])
self.assertTrue(loader is importer)
self.assertTrue(path in sys.path_importer_cache)
self.assertTrue(sys.path_importer_cache[path] is importer)
def get_importer(path_item):
"""Retrieve a PEP 302 importer for the given path item
The returned importer is cached in sys.path_importer_cache
if it was newly created by a path hook.
If there is no importer, a wrapper around the basic import
machinery is returned. This wrapper is never inserted into
the importer cache (None is inserted instead).
The cache (or part of it) can be cleared manually if a
rescan of sys.path_hooks is necessary.
"""
try:
importer = sys.path_importer_cache[path_item]
except KeyError:
for path_hook in sys.path_hooks:
try:
importer = path_hook(path_item)
break
except ImportError:
pass
else:
importer = None
sys.path_importer_cache.setdefault(path_item, importer)
if importer is None:
try:
importer = ImpImporter(path_item)
except ImportError:
importer = None
return importer
def get_sys_path_hooks(self):
return id(sys.path_hooks), sys.path_hooks, sys.path_hooks[:]
def restore_sys_path_hooks(self, saved_hooks):
sys.path_hooks = saved_hooks[1]
sys.path_hooks[:] = saved_hooks[2]
def tearDown(self):
sys.path[:] = self.path
sys.meta_path[:] = self.meta_path
sys.path_hooks[:] = self.path_hooks
sys.path_importer_cache.clear()
def __init__(self, path=test_path):
if path != test_path:
# if out class is on sys.path_hooks, we must raise
# ImportError for any path item that we can't handle.
raise ImportError
self.path = path
def setUp(self):
self.path = sys.path[:]
self.meta_path = sys.meta_path[:]
self.path_hooks = sys.path_hooks[:]
sys.path_importer_cache.clear()
self.modules_before = support.modules_setup()
def tearDown(self):
sys.path[:] = self.path
sys.meta_path[:] = self.meta_path
sys.path_hooks[:] = self.path_hooks
sys.path_importer_cache.clear()
support.modules_cleanup(*self.modules_before)
def testPathHook(self):
sys.path_hooks.append(PathImporter)
sys.path.append(test_path)
self.doTestImports()
def install(compiler, suffixes):
filefinder = [(f, i) for i, f in enumerate(sys.path_hooks)
if repr(f).find('.path_hook_for_FileFinder') != -1]
if filefinder:
filefinder, fpos = filefinder[0]
sys.path_hooks[fpos] = PolyFileFinder.path_hook(*(_suffixer(_get_supported_file_loaders())))
sys.path_importer_cache = {}
pkgutil.iter_importer_modules.register(PolyFileFinder, _poly_file_finder_modules)
PolyFileFinder._install(compiler, suffixes)
def _get_importer(path_name):
"""Python version of PyImport_GetImporter C API function"""
cache = sys.path_importer_cache
try:
importer = cache[path_name]
except KeyError:
# Not yet cached. Flag as using the
# standard machinery until we finish
# checking the hooks
cache[path_name] = None
for hook in sys.path_hooks:
try:
importer = hook(path_name)
break
except ImportError:
pass
else:
# The following check looks a bit odd. The trick is that
# NullImporter raises ImportError if the supplied path is a
# *valid* directory entry (and hence able to be handled
# by the standard import machinery)
try:
importer = imp.NullImporter(path_name)
except ImportError:
return None
cache[path_name] = importer
return importer
def get_importer(path_item):
"""Retrieve a PEP 302 importer for the given path item
The returned importer is cached in sys.path_importer_cache
if it was newly created by a path hook.
If there is no importer, a wrapper around the basic import
machinery is returned. This wrapper is never inserted into
the importer cache (None is inserted instead).
The cache (or part of it) can be cleared manually if a
rescan of sys.path_hooks is necessary.
"""
try:
importer = sys.path_importer_cache[path_item]
except KeyError:
for path_hook in sys.path_hooks:
try:
importer = path_hook(path_item)
break
except ImportError:
pass
else:
importer = None
sys.path_importer_cache.setdefault(path_item, importer)
if importer is None:
try:
importer = ImpImporter(path_item)
except ImportError:
importer = None
return importer
def __init__(self, path=test_path):
if path != test_path:
# if out class is on sys.path_hooks, we must raise
# ImportError for any path item that we can't handle.
raise ImportError
self.path = path
def setUp(self):
self.path = sys.path[:]
self.meta_path = sys.meta_path[:]
self.path_hooks = sys.path_hooks[:]
sys.path_importer_cache.clear()
self.modules_before = sys.modules.copy()
def tearDown(self):
sys.path[:] = self.path
sys.meta_path[:] = self.meta_path
sys.path_hooks[:] = self.path_hooks
sys.path_importer_cache.clear()
sys.modules.clear()
sys.modules.update(self.modules_before)
def testImpWrapper(self):
i = ImpWrapper()
sys.meta_path.append(i)
sys.path_hooks.append(ImpWrapper)
mnames = ("colorsys", "urlparse", "distutils.core", "compiler.misc")
for mname in mnames:
parent = mname.split(".")[0]
for n in sys.modules.keys():
if n.startswith(parent):
del sys.modules[n]
with test_support.check_warnings(("The compiler package is deprecated "
"and removed", DeprecationWarning)):
for mname in mnames:
m = __import__(mname, globals(), locals(), ["__dummy__"])
m.__loader__ # to make sure we actually handled the import
def _get_importer(path_name):
"""Python version of PyImport_GetImporter C API function"""
cache = sys.path_importer_cache
try:
importer = cache[path_name]
except KeyError:
# Not yet cached. Flag as using the
# standard machinery until we finish
# checking the hooks
cache[path_name] = None
for hook in sys.path_hooks:
try:
importer = hook(path_name)
break
except ImportError:
pass
else:
# The following check looks a bit odd. The trick is that
# NullImporter raises ImportError if the supplied path is a
# *valid* directory entry (and hence able to be handled
# by the standard import machinery)
try:
importer = imp.NullImporter(path_name)
except ImportError:
return None
cache[path_name] = importer
return importer
