From e92dc9c23da8cb11f922f28353e6a58928aa5c71 Mon Sep 17 00:00:00 2001 From: Brett Cannon Date: Sat, 25 Jun 2016 10:47:53 -0700 Subject: Fix a scoping issue where an UnboundLocalError was triggered if a lazy-loaded module was already in sys.modules. --- Lib/importlib/util.py | 2 +- Lib/test/test_importlib/test_lazy.py | 16 +++++++++++++--- Misc/NEWS | 4 ++++ 3 files changed, 18 insertions(+), 4 deletions(-) diff --git a/Lib/importlib/util.py b/Lib/importlib/util.py index 4525b3f..e1fa07a 100644 --- a/Lib/importlib/util.py +++ b/Lib/importlib/util.py @@ -241,7 +241,7 @@ class _LazyModule(types.ModuleType): if id(self) != id(sys.modules[original_name]): msg = ('module object for {!r} substituted in sys.modules ' 'during a lazy load') - raise ValueError(msg.format(original_name)) + raise ValueError(msg.format(original_name)) # Update after loading since that's what would happen in an eager # loading situation. self.__dict__.update(attrs_updated) diff --git a/Lib/test/test_importlib/test_lazy.py b/Lib/test/test_importlib/test_lazy.py index 774b7a4..cc383c2 100644 --- a/Lib/test/test_importlib/test_lazy.py +++ b/Lib/test/test_importlib/test_lazy.py @@ -1,6 +1,8 @@ import importlib from importlib import abc from importlib import util +import sys +import types import unittest from . import util as test_util @@ -122,12 +124,20 @@ class LazyLoaderTests(unittest.TestCase): self.assertFalse(hasattr(module, '__name__')) def test_module_substitution_error(self): - source_code = 'import sys; sys.modules[__name__] = 42' - module = self.new_module(source_code) with test_util.uncache(TestingImporter.module_name): - with self.assertRaises(ValueError): + fresh_module = types.ModuleType(TestingImporter.module_name) + sys.modules[TestingImporter.module_name] = fresh_module + module = self.new_module() + with self.assertRaisesRegex(ValueError, "substituted"): module.__name__ + def test_module_already_in_sys(self): + with test_util.uncache(TestingImporter.module_name): + module = self.new_module() + sys.modules[TestingImporter.module_name] = module + # Force the load; just care that no exception is raised. + module.__name__ + if __name__ == '__main__': unittest.main() diff --git a/Misc/NEWS b/Misc/NEWS index 49304ba..f580afe 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -13,6 +13,10 @@ Core and Builtins Library ------- +- Fix a scoping issue in importlib.util.LazyLoader which triggered an + UnboundLocalError when lazy-loading a module that was already put into + sys.modules. + - Issue #27079: Fixed curses.ascii functions isblank(), iscntrl() and ispunct(). - Issue #26754: Some functions (compile() etc) accepted a filename argument -- cgit v0.12