cpython/Lib/test/test_importlib/test_util.py

318 lines
11 KiB
Python

from importlib import util
from . import util as test_util
import imp
import sys
from test import support
import types
import unittest
import warnings
class ModuleToLoadTests(unittest.TestCase):
module_name = 'ModuleManagerTest_module'
def setUp(self):
support.unload(self.module_name)
self.addCleanup(support.unload, self.module_name)
def test_new_module(self):
# Test a new module is created, inserted into sys.modules, has
# __initializing__ set to True after entering the context manager,
# and __initializing__ set to False after exiting.
with util.module_to_load(self.module_name) as module:
self.assertIn(self.module_name, sys.modules)
self.assertIs(sys.modules[self.module_name], module)
self.assertTrue(module.__initializing__)
self.assertFalse(module.__initializing__)
def test_new_module_failed(self):
# Test the module is removed from sys.modules.
try:
with util.module_to_load(self.module_name) as module:
self.assertIn(self.module_name, sys.modules)
raise exception
except Exception:
self.assertNotIn(self.module_name, sys.modules)
else:
self.fail('importlib.util.module_to_load swallowed an exception')
def test_reload(self):
# Test that the same module is in sys.modules.
created_module = imp.new_module(self.module_name)
sys.modules[self.module_name] = created_module
with util.module_to_load(self.module_name) as module:
self.assertIs(module, created_module)
def test_reload_failed(self):
# Test that the module was left in sys.modules.
created_module = imp.new_module(self.module_name)
sys.modules[self.module_name] = created_module
try:
with util.module_to_load(self.module_name) as module:
raise Exception
except Exception:
self.assertIn(self.module_name, sys.modules)
else:
self.fail('importlib.util.module_to_load swallowed an exception')
def test_reset_name(self):
# If reset_name is true then module.__name__ = name, else leave it be.
odd_name = 'not your typical name'
created_module = imp.new_module(self.module_name)
created_module.__name__ = odd_name
sys.modules[self.module_name] = created_module
with util.module_to_load(self.module_name) as module:
self.assertEqual(module.__name__, self.module_name)
created_module.__name__ = odd_name
with util.module_to_load(self.module_name, reset_name=False) as module:
self.assertEqual(module.__name__, odd_name)
class ModuleForLoaderTests(unittest.TestCase):
"""Tests for importlib.util.module_for_loader."""
@staticmethod
def module_for_loader(func):
with warnings.catch_warnings():
warnings.simplefilter('ignore', PendingDeprecationWarning)
return util.module_for_loader(func)
def test_warning(self):
# Should raise a PendingDeprecationWarning when used.
with warnings.catch_warnings():
warnings.simplefilter('error', PendingDeprecationWarning)
with self.assertRaises(PendingDeprecationWarning):
func = util.module_for_loader(lambda x: x)
def return_module(self, name):
fxn = self.module_for_loader(lambda self, module: module)
return fxn(self, name)
def raise_exception(self, name):
def to_wrap(self, module):
raise ImportError
fxn = self.module_for_loader(to_wrap)
try:
fxn(self, name)
except ImportError:
pass
def test_new_module(self):
# Test that when no module exists in sys.modules a new module is
# created.
module_name = 'a.b.c'
with test_util.uncache(module_name):
module = self.return_module(module_name)
self.assertIn(module_name, sys.modules)
self.assertIsInstance(module, types.ModuleType)
self.assertEqual(module.__name__, module_name)
def test_reload(self):
# Test that a module is reused if already in sys.modules.
class FakeLoader:
def is_package(self, name):
return True
@self.module_for_loader
def load_module(self, module):
return module
name = 'a.b.c'
module = imp.new_module('a.b.c')
module.__loader__ = 42
module.__package__ = 42
with test_util.uncache(name):
sys.modules[name] = module
loader = FakeLoader()
returned_module = loader.load_module(name)
self.assertIs(returned_module, sys.modules[name])
self.assertEqual(module.__loader__, loader)
self.assertEqual(module.__package__, name)
def test_new_module_failure(self):
# Test that a module is removed from sys.modules if added but an
# exception is raised.
name = 'a.b.c'
with test_util.uncache(name):
self.raise_exception(name)
self.assertNotIn(name, sys.modules)
def test_reload_failure(self):
# Test that a failure on reload leaves the module in-place.
name = 'a.b.c'
module = imp.new_module(name)
with test_util.uncache(name):
sys.modules[name] = module
self.raise_exception(name)
self.assertIs(module, sys.modules[name])
def test_decorator_attrs(self):
def fxn(self, module): pass
wrapped = self.module_for_loader(fxn)
self.assertEqual(wrapped.__name__, fxn.__name__)
self.assertEqual(wrapped.__qualname__, fxn.__qualname__)
def test_false_module(self):
# If for some odd reason a module is considered false, still return it
# from sys.modules.
class FalseModule(types.ModuleType):
def __bool__(self): return False
name = 'mod'
module = FalseModule(name)
with test_util.uncache(name):
self.assertFalse(module)
sys.modules[name] = module
given = self.return_module(name)
self.assertIs(given, module)
def test_attributes_set(self):
# __name__, __loader__, and __package__ should be set (when
# is_package() is defined; undefined implicitly tested elsewhere).
class FakeLoader:
def __init__(self, is_package):
self._pkg = is_package
def is_package(self, name):
return self._pkg
@self.module_for_loader
def load_module(self, module):
return module
name = 'pkg.mod'
with test_util.uncache(name):
loader = FakeLoader(False)
module = loader.load_module(name)
self.assertEqual(module.__name__, name)
self.assertIs(module.__loader__, loader)
self.assertEqual(module.__package__, 'pkg')
name = 'pkg.sub'
with test_util.uncache(name):
loader = FakeLoader(True)
module = loader.load_module(name)
self.assertEqual(module.__name__, name)
self.assertIs(module.__loader__, loader)
self.assertEqual(module.__package__, name)
class SetPackageTests(unittest.TestCase):
"""Tests for importlib.util.set_package."""
def verify(self, module, expect):
"""Verify the module has the expected value for __package__ after
passing through set_package."""
fxn = lambda: module
wrapped = util.set_package(fxn)
wrapped()
self.assertTrue(hasattr(module, '__package__'))
self.assertEqual(expect, module.__package__)
def test_top_level(self):
# __package__ should be set to the empty string if a top-level module.
# Implicitly tests when package is set to None.
module = imp.new_module('module')
module.__package__ = None
self.verify(module, '')
def test_package(self):
# Test setting __package__ for a package.
module = imp.new_module('pkg')
module.__path__ = ['<path>']
module.__package__ = None
self.verify(module, 'pkg')
def test_submodule(self):
# Test __package__ for a module in a package.
module = imp.new_module('pkg.mod')
module.__package__ = None
self.verify(module, 'pkg')
def test_setting_if_missing(self):
# __package__ should be set if it is missing.
module = imp.new_module('mod')
if hasattr(module, '__package__'):
delattr(module, '__package__')
self.verify(module, '')
def test_leaving_alone(self):
# If __package__ is set and not None then leave it alone.
for value in (True, False):
module = imp.new_module('mod')
module.__package__ = value
self.verify(module, value)
def test_decorator_attrs(self):
def fxn(module): pass
wrapped = util.set_package(fxn)
self.assertEqual(wrapped.__name__, fxn.__name__)
self.assertEqual(wrapped.__qualname__, fxn.__qualname__)
class SetLoaderTests(unittest.TestCase):
"""Tests importlib.util.set_loader()."""
class DummyLoader:
@util.set_loader
def load_module(self, module):
return self.module
def test_no_attribute(self):
loader = self.DummyLoader()
loader.module = imp.new_module('blah')
try:
del loader.module.__loader__
except AttributeError:
pass
self.assertEqual(loader, loader.load_module('blah').__loader__)
def test_attribute_is_None(self):
loader = self.DummyLoader()
loader.module = imp.new_module('blah')
loader.module.__loader__ = None
self.assertEqual(loader, loader.load_module('blah').__loader__)
def test_not_reset(self):
loader = self.DummyLoader()
loader.module = imp.new_module('blah')
loader.module.__loader__ = 42
self.assertEqual(42, loader.load_module('blah').__loader__)
class ResolveNameTests(unittest.TestCase):
"""Tests importlib.util.resolve_name()."""
def test_absolute(self):
# bacon
self.assertEqual('bacon', util.resolve_name('bacon', None))
def test_aboslute_within_package(self):
# bacon in spam
self.assertEqual('bacon', util.resolve_name('bacon', 'spam'))
def test_no_package(self):
# .bacon in ''
with self.assertRaises(ValueError):
util.resolve_name('.bacon', '')
def test_in_package(self):
# .bacon in spam
self.assertEqual('spam.eggs.bacon',
util.resolve_name('.bacon', 'spam.eggs'))
def test_other_package(self):
# ..bacon in spam.bacon
self.assertEqual('spam.bacon',
util.resolve_name('..bacon', 'spam.eggs'))
def test_escape(self):
# ..bacon in spam
with self.assertRaises(ValueError):
util.resolve_name('..bacon', 'spam')
if __name__ == '__main__':
unittest.main()