cpython/Lib/test/test_importlib/test_util.py

209 lines
6.7 KiB
Python

from importlib import util
from . import util as test_util
import imp
import sys
import types
import unittest
class ModuleForLoaderTests(unittest.TestCase):
"""Tests for importlib.util.module_for_loader."""
def return_module(self, name):
fxn = util.module_for_loader(lambda self, module: module)
return fxn(self, name)
def raise_exception(self, name):
def to_wrap(self, module):
raise ImportError
fxn = util.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.
name = 'a.b.c'
module = imp.new_module('a.b.c')
with test_util.uncache(name):
sys.modules[name] = module
returned_module = self.return_module(name)
self.assertIs(returned_module, sys.modules[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 = util.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
@util.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 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')
def test_main():
from test import support
support.run_unittest(
ModuleForLoaderTests,
SetPackageTests,
ResolveNameTests
)
if __name__ == '__main__':
test_main()