def test_deprecated_module_loader_load_module_wrapper():
hello_module = types.ModuleType('hello')
class StubLoader(importlib.abc.Loader):
def load_module(self, fullname: str) -> ModuleType:
# we simulate loader behavior - it is assumed that loaders will set the
# module cache with the loaded module
sys.modules[fullname] = hello_module
return hello_module
with pytest.raises(AssertionError,
match="for old was asked to load something_else"):
DeprecatedModuleLoader(StubLoader(), 'old',
'new').load_module('something_else')
# new module already loaded
sys.modules['new_hello'] = hello_module
assert (DeprecatedModuleLoader(
StubLoader(), 'old_hello',
'new_hello').load_module('old_hello') == hello_module)
assert 'old_hello' in sys.modules and sys.modules[
'old_hello'] == sys.modules['new_hello']
del sys.modules['new_hello']
del sys.modules['old_hello']
# new module is not loaded
assert (DeprecatedModuleLoader(
StubLoader(), 'old_hello',
'new_hello').load_module('old_hello') == hello_module)
assert 'new_hello' in sys.modules
assert 'old_hello' in sys.modules and sys.modules[
'old_hello'] == sys.modules['new_hello']
del sys.modules['new_hello']
del sys.modules['old_hello']
def test_loader_wrappers():
hello_module = types.ModuleType('hello')
class StubLoader(importlib.abc.Loader):
def module_repr(self, module: ModuleType) -> str:
return 'hello'
def load_module(self, fullname: str) -> ModuleType:
return hello_module
module = types.ModuleType('old')
assert DeprecatedModuleLoader(StubLoader(), 'old',
'new').module_repr(module) == 'hello'
assert DeprecatedModuleLoader(StubLoader(), 'old',
'new').load_module('test') == hello_module
def test_loader_create_module():
class EmptyLoader(importlib.abc.Loader):
pass
dml = DeprecatedModuleLoader(EmptyLoader(), 'old', 'new')
# the default implementation is from the abstract class, which is just pass
assert dml.create_module('test') is None
fake_mod = ModuleType('hello')
class CreateModuleLoader(importlib.abc.Loader):
def create_module(self, spec: ModuleSpec) -> Optional[ModuleType]:
return fake_mod
assert (DeprecatedModuleLoader(CreateModuleLoader(), 'old',
'new').create_module(None) == fake_mod)
def test_deprecated_module_loader_repr():
class StubLoader(importlib.abc.Loader):
def module_repr(self, module: ModuleType) -> str:
return 'hello'
module = types.ModuleType('old')
assert (DeprecatedModuleLoader(StubLoader(), 'old_hello',
'new_hello').module_repr(module) == 'hello')
def test_loader_cleanup_on_failure():
class FakeLoader(importlib.abc.Loader):
def exec_module(self, module: ModuleType) -> None:
raise KeyboardInterrupt()
with pytest.raises(KeyboardInterrupt):
module = types.ModuleType('old')
DeprecatedModuleLoader(FakeLoader(), 'old', 'new').exec_module(module)
assert 'old' not in sys.modules
assert 'new' not in sys.modules