cpython/Lib/test/test_pkgutil.py
Brett Cannon 8447c703d1 Issue #14710: Fix both pkgutil.find_loader() and get_loader() to not
raise an exception when a module doesn't exist.

Thanks to Pavel Aslanov for the bug report.
2014-05-23 12:30:37 -04:00

411 lines
14 KiB
Python

from test.support import run_unittest, unload, check_warnings, CleanImport
import unittest
import sys
import importlib
from importlib.util import spec_from_file_location
import pkgutil
import os
import os.path
import tempfile
import types
import shutil
import zipfile
# Note: pkgutil.walk_packages is currently tested in test_runpy. This is
# a hack to get a major issue resolved for 3.3b2. Longer term, it should
# be moved back here, perhaps by factoring out the helper code for
# creating interesting package layouts to a separate module.
# Issue #15348 declares this is indeed a dodgy hack ;)
class PkgutilTests(unittest.TestCase):
def setUp(self):
self.dirname = tempfile.mkdtemp()
self.addCleanup(shutil.rmtree, self.dirname)
sys.path.insert(0, self.dirname)
def tearDown(self):
del sys.path[0]
def test_getdata_filesys(self):
pkg = 'test_getdata_filesys'
# Include a LF and a CRLF, to test that binary data is read back
RESOURCE_DATA = b'Hello, world!\nSecond line\r\nThird line'
# Make a package with some resources
package_dir = os.path.join(self.dirname, pkg)
os.mkdir(package_dir)
# Empty init.py
f = open(os.path.join(package_dir, '__init__.py'), "wb")
f.close()
# Resource files, res.txt, sub/res.txt
f = open(os.path.join(package_dir, 'res.txt'), "wb")
f.write(RESOURCE_DATA)
f.close()
os.mkdir(os.path.join(package_dir, 'sub'))
f = open(os.path.join(package_dir, 'sub', 'res.txt'), "wb")
f.write(RESOURCE_DATA)
f.close()
# Check we can read the resources
res1 = pkgutil.get_data(pkg, 'res.txt')
self.assertEqual(res1, RESOURCE_DATA)
res2 = pkgutil.get_data(pkg, 'sub/res.txt')
self.assertEqual(res2, RESOURCE_DATA)
del sys.modules[pkg]
def test_getdata_zipfile(self):
zip = 'test_getdata_zipfile.zip'
pkg = 'test_getdata_zipfile'
# Include a LF and a CRLF, to test that binary data is read back
RESOURCE_DATA = b'Hello, world!\nSecond line\r\nThird line'
# Make a package with some resources
zip_file = os.path.join(self.dirname, zip)
z = zipfile.ZipFile(zip_file, 'w')
# Empty init.py
z.writestr(pkg + '/__init__.py', "")
# Resource files, res.txt, sub/res.txt
z.writestr(pkg + '/res.txt', RESOURCE_DATA)
z.writestr(pkg + '/sub/res.txt', RESOURCE_DATA)
z.close()
# Check we can read the resources
sys.path.insert(0, zip_file)
res1 = pkgutil.get_data(pkg, 'res.txt')
self.assertEqual(res1, RESOURCE_DATA)
res2 = pkgutil.get_data(pkg, 'sub/res.txt')
self.assertEqual(res2, RESOURCE_DATA)
names = []
for loader, name, ispkg in pkgutil.iter_modules([zip_file]):
names.append(name)
self.assertEqual(names, ['test_getdata_zipfile'])
del sys.path[0]
del sys.modules[pkg]
def test_unreadable_dir_on_syspath(self):
# issue7367 - walk_packages failed if unreadable dir on sys.path
package_name = "unreadable_package"
d = os.path.join(self.dirname, package_name)
# this does not appear to create an unreadable dir on Windows
# but the test should not fail anyway
os.mkdir(d, 0)
self.addCleanup(os.rmdir, d)
for t in pkgutil.walk_packages(path=[self.dirname]):
self.fail("unexpected package found")
class PkgutilPEP302Tests(unittest.TestCase):
class MyTestLoader(object):
def exec_module(self, mod):
# Count how many times the module is reloaded
mod.__dict__['loads'] = mod.__dict__.get('loads', 0) + 1
def get_data(self, path):
return "Hello, world!"
class MyTestImporter(object):
def find_spec(self, fullname, path=None, target=None):
loader = PkgutilPEP302Tests.MyTestLoader()
return spec_from_file_location(fullname,
'<%s>' % loader.__class__.__name__,
loader=loader,
submodule_search_locations=[])
def setUp(self):
sys.meta_path.insert(0, self.MyTestImporter())
def tearDown(self):
del sys.meta_path[0]
def test_getdata_pep302(self):
# Use a dummy importer/loader
self.assertEqual(pkgutil.get_data('foo', 'dummy'), "Hello, world!")
del sys.modules['foo']
def test_alreadyloaded(self):
# Ensure that get_data works without reloading - the "loads" module
# variable in the example loader should count how many times a reload
# occurs.
import foo
self.assertEqual(foo.loads, 1)
self.assertEqual(pkgutil.get_data('foo', 'dummy'), "Hello, world!")
self.assertEqual(foo.loads, 1)
del sys.modules['foo']
# These tests, especially the setup and cleanup, are hideous. They
# need to be cleaned up once issue 14715 is addressed.
class ExtendPathTests(unittest.TestCase):
def create_init(self, pkgname):
dirname = tempfile.mkdtemp()
sys.path.insert(0, dirname)
pkgdir = os.path.join(dirname, pkgname)
os.mkdir(pkgdir)
with open(os.path.join(pkgdir, '__init__.py'), 'w') as fl:
fl.write('from pkgutil import extend_path\n__path__ = extend_path(__path__, __name__)\n')
return dirname
def create_submodule(self, dirname, pkgname, submodule_name, value):
module_name = os.path.join(dirname, pkgname, submodule_name + '.py')
with open(module_name, 'w') as fl:
print('value={}'.format(value), file=fl)
def test_simple(self):
pkgname = 'foo'
dirname_0 = self.create_init(pkgname)
dirname_1 = self.create_init(pkgname)
self.create_submodule(dirname_0, pkgname, 'bar', 0)
self.create_submodule(dirname_1, pkgname, 'baz', 1)
import foo.bar
import foo.baz
# Ensure we read the expected values
self.assertEqual(foo.bar.value, 0)
self.assertEqual(foo.baz.value, 1)
# Ensure the path is set up correctly
self.assertEqual(sorted(foo.__path__),
sorted([os.path.join(dirname_0, pkgname),
os.path.join(dirname_1, pkgname)]))
# Cleanup
shutil.rmtree(dirname_0)
shutil.rmtree(dirname_1)
del sys.path[0]
del sys.path[0]
del sys.modules['foo']
del sys.modules['foo.bar']
del sys.modules['foo.baz']
# Another awful testing hack to be cleaned up once the test_runpy
# helpers are factored out to a common location
def test_iter_importers(self):
iter_importers = pkgutil.iter_importers
get_importer = pkgutil.get_importer
pkgname = 'spam'
modname = 'eggs'
dirname = self.create_init(pkgname)
pathitem = os.path.join(dirname, pkgname)
fullname = '{}.{}'.format(pkgname, modname)
sys.modules.pop(fullname, None)
sys.modules.pop(pkgname, None)
try:
self.create_submodule(dirname, pkgname, modname, 0)
importlib.import_module(fullname)
importers = list(iter_importers(fullname))
expected_importer = get_importer(pathitem)
for finder in importers:
spec = pkgutil._get_spec(finder, fullname)
loader = spec.loader
try:
loader = loader.loader
except AttributeError:
# For now we still allow raw loaders from
# find_module().
pass
self.assertIsInstance(finder, importlib.machinery.FileFinder)
self.assertEqual(finder, expected_importer)
self.assertIsInstance(loader,
importlib.machinery.SourceFileLoader)
self.assertIsNone(pkgutil._get_spec(finder, pkgname))
with self.assertRaises(ImportError):
list(iter_importers('invalid.module'))
with self.assertRaises(ImportError):
list(iter_importers('.spam'))
finally:
shutil.rmtree(dirname)
del sys.path[0]
try:
del sys.modules['spam']
del sys.modules['spam.eggs']
except KeyError:
pass
def test_mixed_namespace(self):
pkgname = 'foo'
dirname_0 = self.create_init(pkgname)
dirname_1 = self.create_init(pkgname)
self.create_submodule(dirname_0, pkgname, 'bar', 0)
# Turn this into a PEP 420 namespace package
os.unlink(os.path.join(dirname_0, pkgname, '__init__.py'))
self.create_submodule(dirname_1, pkgname, 'baz', 1)
import foo.bar
import foo.baz
# Ensure we read the expected values
self.assertEqual(foo.bar.value, 0)
self.assertEqual(foo.baz.value, 1)
# Ensure the path is set up correctly
self.assertEqual(sorted(foo.__path__),
sorted([os.path.join(dirname_0, pkgname),
os.path.join(dirname_1, pkgname)]))
# Cleanup
shutil.rmtree(dirname_0)
shutil.rmtree(dirname_1)
del sys.path[0]
del sys.path[0]
del sys.modules['foo']
del sys.modules['foo.bar']
del sys.modules['foo.baz']
# XXX: test .pkg files
class NestedNamespacePackageTest(unittest.TestCase):
def setUp(self):
self.basedir = tempfile.mkdtemp()
self.old_path = sys.path[:]
def tearDown(self):
sys.path[:] = self.old_path
shutil.rmtree(self.basedir)
def create_module(self, name, contents):
base, final = name.rsplit('.', 1)
base_path = os.path.join(self.basedir, base.replace('.', os.path.sep))
os.makedirs(base_path, exist_ok=True)
with open(os.path.join(base_path, final + ".py"), 'w') as f:
f.write(contents)
def test_nested(self):
pkgutil_boilerplate = (
'import pkgutil; '
'__path__ = pkgutil.extend_path(__path__, __name__)')
self.create_module('a.pkg.__init__', pkgutil_boilerplate)
self.create_module('b.pkg.__init__', pkgutil_boilerplate)
self.create_module('a.pkg.subpkg.__init__', pkgutil_boilerplate)
self.create_module('b.pkg.subpkg.__init__', pkgutil_boilerplate)
self.create_module('a.pkg.subpkg.c', 'c = 1')
self.create_module('b.pkg.subpkg.d', 'd = 2')
sys.path.insert(0, os.path.join(self.basedir, 'a'))
sys.path.insert(0, os.path.join(self.basedir, 'b'))
import pkg
self.addCleanup(unload, 'pkg')
self.assertEqual(len(pkg.__path__), 2)
import pkg.subpkg
self.addCleanup(unload, 'pkg.subpkg')
self.assertEqual(len(pkg.subpkg.__path__), 2)
from pkg.subpkg.c import c
from pkg.subpkg.d import d
self.assertEqual(c, 1)
self.assertEqual(d, 2)
class ImportlibMigrationTests(unittest.TestCase):
# With full PEP 302 support in the standard import machinery, the
# PEP 302 emulation in this module is in the process of being
# deprecated in favour of importlib proper
def check_deprecated(self):
return check_warnings(
("This emulation is deprecated, use 'importlib' instead",
DeprecationWarning))
def test_importer_deprecated(self):
with self.check_deprecated():
x = pkgutil.ImpImporter("")
def test_loader_deprecated(self):
with self.check_deprecated():
x = pkgutil.ImpLoader("", "", "", "")
def test_get_loader_avoids_emulation(self):
with check_warnings() as w:
self.assertIsNotNone(pkgutil.get_loader("sys"))
self.assertIsNotNone(pkgutil.get_loader("os"))
self.assertIsNotNone(pkgutil.get_loader("test.support"))
self.assertEqual(len(w.warnings), 0)
def test_get_loader_handles_missing_loader_attribute(self):
global __loader__
this_loader = __loader__
del __loader__
try:
with check_warnings() as w:
self.assertIsNotNone(pkgutil.get_loader(__name__))
self.assertEqual(len(w.warnings), 0)
finally:
__loader__ = this_loader
def test_get_loader_handles_missing_spec_attribute(self):
name = 'spam'
mod = type(sys)(name)
del mod.__spec__
with CleanImport(name):
sys.modules[name] = mod
loader = pkgutil.get_loader(name)
self.assertIsNone(loader)
def test_get_loader_handles_spec_attribute_none(self):
name = 'spam'
mod = type(sys)(name)
mod.__spec__ = None
with CleanImport(name):
sys.modules[name] = mod
loader = pkgutil.get_loader(name)
self.assertIsNone(loader)
def test_get_loader_None_in_sys_modules(self):
name = 'totally bogus'
sys.modules[name] = None
try:
loader = pkgutil.get_loader(name)
finally:
del sys.modules[name]
self.assertIsNone(loader)
def test_find_loader_missing_module(self):
name = 'totally bogus'
loader = pkgutil.find_loader(name)
self.assertIsNone(loader)
def test_find_loader_avoids_emulation(self):
with check_warnings() as w:
self.assertIsNotNone(pkgutil.find_loader("sys"))
self.assertIsNotNone(pkgutil.find_loader("os"))
self.assertIsNotNone(pkgutil.find_loader("test.support"))
self.assertEqual(len(w.warnings), 0)
def test_get_importer_avoids_emulation(self):
# We use an illegal path so *none* of the path hooks should fire
with check_warnings() as w:
self.assertIsNone(pkgutil.get_importer("*??"))
self.assertEqual(len(w.warnings), 0)
def test_iter_importers_avoids_emulation(self):
with check_warnings() as w:
for importer in pkgutil.iter_importers(): pass
self.assertEqual(len(w.warnings), 0)
def test_main():
run_unittest(PkgutilTests, PkgutilPEP302Tests, ExtendPathTests,
NestedNamespacePackageTest, ImportlibMigrationTests)
# this is necessary if test is run repeated (like when finding leaks)
import zipimport
import importlib
zipimport._zip_directory_cache.clear()
importlib.invalidate_caches()
if __name__ == '__main__':
test_main()