django/tests/utils_tests/test_module_loading.py

271 lines
11 KiB
Python

import imp
from importlib import import_module
import os
import sys
import unittest
import warnings
from zipimport import zipimporter
from django.core.exceptions import ImproperlyConfigured
from django.test import SimpleTestCase, modify_settings
from django.test.utils import IgnoreDeprecationWarningsMixin, extend_sys_path
from django.utils import six
from django.utils.deprecation import RemovedInDjango19Warning
from django.utils.module_loading import (autodiscover_modules, import_by_path, import_string,
module_has_submodule)
from django.utils._os import upath
class DefaultLoader(unittest.TestCase):
def setUp(self):
sys.meta_path.insert(0, ProxyFinder())
def tearDown(self):
sys.meta_path.pop(0)
def test_loader(self):
"Normal module existence can be tested"
test_module = import_module('utils_tests.test_module')
test_no_submodule = import_module(
'utils_tests.test_no_submodule')
# An importable child
self.assertTrue(module_has_submodule(test_module, 'good_module'))
mod = import_module('utils_tests.test_module.good_module')
self.assertEqual(mod.content, 'Good Module')
# A child that exists, but will generate an import error if loaded
self.assertTrue(module_has_submodule(test_module, 'bad_module'))
self.assertRaises(ImportError, import_module, 'utils_tests.test_module.bad_module')
# A child that doesn't exist
self.assertFalse(module_has_submodule(test_module, 'no_such_module'))
self.assertRaises(ImportError, import_module, 'utils_tests.test_module.no_such_module')
# A child that doesn't exist, but is the name of a package on the path
self.assertFalse(module_has_submodule(test_module, 'django'))
self.assertRaises(ImportError, import_module, 'utils_tests.test_module.django')
# Don't be confused by caching of import misses
import types # NOQA: causes attempted import of utils_tests.types
self.assertFalse(module_has_submodule(sys.modules['utils_tests'], 'types'))
# A module which doesn't have a __path__ (so no submodules)
self.assertFalse(module_has_submodule(test_no_submodule, 'anything'))
self.assertRaises(ImportError, import_module,
'utils_tests.test_no_submodule.anything')
class EggLoader(unittest.TestCase):
def setUp(self):
self.egg_dir = '%s/eggs' % os.path.dirname(upath(__file__))
def tearDown(self):
sys.path_importer_cache.clear()
sys.modules.pop('egg_module.sub1.sub2.bad_module', None)
sys.modules.pop('egg_module.sub1.sub2.good_module', None)
sys.modules.pop('egg_module.sub1.sub2', None)
sys.modules.pop('egg_module.sub1', None)
sys.modules.pop('egg_module.bad_module', None)
sys.modules.pop('egg_module.good_module', None)
sys.modules.pop('egg_module', None)
def test_shallow_loader(self):
"Module existence can be tested inside eggs"
egg_name = '%s/test_egg.egg' % self.egg_dir
with extend_sys_path(egg_name):
egg_module = import_module('egg_module')
# An importable child
self.assertTrue(module_has_submodule(egg_module, 'good_module'))
mod = import_module('egg_module.good_module')
self.assertEqual(mod.content, 'Good Module')
# A child that exists, but will generate an import error if loaded
self.assertTrue(module_has_submodule(egg_module, 'bad_module'))
self.assertRaises(ImportError, import_module, 'egg_module.bad_module')
# A child that doesn't exist
self.assertFalse(module_has_submodule(egg_module, 'no_such_module'))
self.assertRaises(ImportError, import_module, 'egg_module.no_such_module')
def test_deep_loader(self):
"Modules deep inside an egg can still be tested for existence"
egg_name = '%s/test_egg.egg' % self.egg_dir
with extend_sys_path(egg_name):
egg_module = import_module('egg_module.sub1.sub2')
# An importable child
self.assertTrue(module_has_submodule(egg_module, 'good_module'))
mod = import_module('egg_module.sub1.sub2.good_module')
self.assertEqual(mod.content, 'Deep Good Module')
# A child that exists, but will generate an import error if loaded
self.assertTrue(module_has_submodule(egg_module, 'bad_module'))
self.assertRaises(ImportError, import_module, 'egg_module.sub1.sub2.bad_module')
# A child that doesn't exist
self.assertFalse(module_has_submodule(egg_module, 'no_such_module'))
self.assertRaises(ImportError, import_module, 'egg_module.sub1.sub2.no_such_module')
class ModuleImportTestCase(IgnoreDeprecationWarningsMixin, unittest.TestCase):
def test_import_by_path(self):
cls = import_by_path('django.utils.module_loading.import_by_path')
self.assertEqual(cls, import_by_path)
# Test exceptions raised
for path in ('no_dots_in_path', 'unexistent.path', 'utils_tests.unexistent'):
self.assertRaises(ImproperlyConfigured, import_by_path, path)
with self.assertRaises(ImproperlyConfigured) as cm:
import_by_path('unexistent.module.path', error_prefix="Foo")
self.assertTrue(str(cm.exception).startswith('Foo'))
def test_import_error_traceback(self):
"""Test preserving the original traceback on an ImportError."""
try:
import_by_path('test_module.bad_module.content')
except ImproperlyConfigured:
traceback = sys.exc_info()[2]
self.assertIsNotNone(traceback.tb_next.tb_next,
'Should have more than the calling frame in the traceback.')
def test_import_by_path_pending_deprecation_warning(self):
with warnings.catch_warnings(record=True) as w:
warnings.simplefilter('always', category=RemovedInDjango19Warning)
cls = import_by_path('django.utils.module_loading.import_by_path')
self.assertEqual(cls, import_by_path)
self.assertEqual(len(w), 1)
self.assertTrue(issubclass(w[-1].category, RemovedInDjango19Warning))
self.assertIn('deprecated', str(w[-1].message))
def test_import_string(self):
cls = import_string('django.utils.module_loading.import_string')
self.assertEqual(cls, import_string)
# Test exceptions raised
self.assertRaises(ImportError, import_string, 'no_dots_in_path')
self.assertRaises(ImportError, import_string, 'utils_tests.unexistent')
self.assertRaises(ImportError, import_string, 'unexistent.path')
@modify_settings(INSTALLED_APPS={'append': 'utils_tests.test_module'})
class AutodiscoverModulesTestCase(SimpleTestCase):
def tearDown(self):
sys.path_importer_cache.clear()
sys.modules.pop('utils_tests.test_module.another_bad_module', None)
sys.modules.pop('utils_tests.test_module.another_good_module', None)
sys.modules.pop('utils_tests.test_module.bad_module', None)
sys.modules.pop('utils_tests.test_module.good_module', None)
sys.modules.pop('utils_tests.test_module', None)
def test_autodiscover_modules_found(self):
autodiscover_modules('good_module')
def test_autodiscover_modules_not_found(self):
autodiscover_modules('missing_module')
def test_autodiscover_modules_found_but_bad_module(self):
with six.assertRaisesRegex(self, ImportError, "No module named '?a_package_name_that_does_not_exist'?"):
autodiscover_modules('bad_module')
def test_autodiscover_modules_several_one_bad_module(self):
with six.assertRaisesRegex(self, ImportError, "No module named '?a_package_name_that_does_not_exist'?"):
autodiscover_modules('good_module', 'bad_module')
def test_autodiscover_modules_several_found(self):
autodiscover_modules('good_module', 'another_good_module')
def test_autodiscover_modules_several_found_with_registry(self):
from .test_module import site
autodiscover_modules('good_module', 'another_good_module', register_to=site)
self.assertEqual(site._registry, {'lorem': 'ipsum'})
def test_validate_registry_keeps_intact(self):
from .test_module import site
with six.assertRaisesRegex(self, Exception, "Some random exception."):
autodiscover_modules('another_bad_module', register_to=site)
self.assertEqual(site._registry, {})
def test_validate_registry_resets_after_erroneous_module(self):
from .test_module import site
with six.assertRaisesRegex(self, Exception, "Some random exception."):
autodiscover_modules('another_good_module', 'another_bad_module', register_to=site)
self.assertEqual(site._registry, {'lorem': 'ipsum'})
def test_validate_registry_resets_after_missing_module(self):
from .test_module import site
autodiscover_modules('does_not_exist', 'another_good_module', 'does_not_exist2', register_to=site)
self.assertEqual(site._registry, {'lorem': 'ipsum'})
class ProxyFinder(object):
def __init__(self):
self._cache = {}
def find_module(self, fullname, path=None):
tail = fullname.rsplit('.', 1)[-1]
try:
fd, fn, info = imp.find_module(tail, path)
if fullname in self._cache:
old_fd = self._cache[fullname][0]
if old_fd:
old_fd.close()
self._cache[fullname] = (fd, fn, info)
except ImportError:
return None
else:
return self # this is a loader as well
def load_module(self, fullname):
if fullname in sys.modules:
return sys.modules[fullname]
fd, fn, info = self._cache[fullname]
try:
return imp.load_module(fullname, fd, fn, info)
finally:
if fd:
fd.close()
class TestFinder(object):
def __init__(self, *args, **kwargs):
self.importer = zipimporter(*args, **kwargs)
def find_module(self, path):
importer = self.importer.find_module(path)
if importer is None:
return
return TestLoader(importer)
class TestLoader(object):
def __init__(self, importer):
self.importer = importer
def load_module(self, name):
mod = self.importer.load_module(name)
mod.__loader__ = self
return mod
class CustomLoader(EggLoader):
"""The Custom Loader test is exactly the same as the EggLoader, but
it uses a custom defined Loader and Finder that is intentionally
split into two classes. Although the EggLoader combines both functions
into one class, this isn't required.
"""
def setUp(self):
super(CustomLoader, self).setUp()
sys.path_hooks.insert(0, TestFinder)
sys.path_importer_cache.clear()
def tearDown(self):
super(CustomLoader, self).tearDown()
sys.path_hooks.pop(0)