[Python-checkins] cpython: Issue #12599: Be more strict in accepting None vs. a false-like object

Wed Apr 18 03:42:15 CEST 2012

http://hg.python.org/cpython/rev/c1399cf7bd6a
changeset: 76384:c1399cf7bd6a
parent: 76381:66bd85bcf916
user: Brett Cannon <brett at python.org>
date: Tue Apr 17 21:41:35 2012 -0400
summary:
 Issue #12599: Be more strict in accepting None vs. a false-like object
in importlib.
Thanks to PJE for pointing out the issue and Nick Coghlan for filing
the bug.
files:
 Lib/importlib/_bootstrap.py | 6 ++--
 Lib/importlib/test/import_/test_path.py | 9 ++++++
 Lib/importlib/test/test_util.py | 16 +++++++++++-
 Misc/NEWS | 4 +++
 Python/importlib.h | Bin 
 5 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/Lib/importlib/_bootstrap.py b/Lib/importlib/_bootstrap.py
--- a/Lib/importlib/_bootstrap.py
+++ b/Lib/importlib/_bootstrap.py
@@ -217,7 +217,7 @@
 """
 def module_for_loader_wrapper(self, fullname, *args, **kwargs):
 module = sys.modules.get(fullname)
- is_reload = bool(module)
+ is_reload = module is not None
 if not is_reload:
 # This must be done before open() is called as the 'io' module
 # implicitly imports 'locale' and would otherwise trigger an
@@ -711,7 +711,7 @@
 If 'hooks' is false then use sys.path_hooks.
 
 """
- if not hooks:
+ if hooks is None:
 hooks = sys.path_hooks
 for hook in hooks:
 try:
@@ -753,7 +753,7 @@
 def find_module(cls, fullname, path=None):
 """Find the module on sys.path or 'path' based on sys.path_hooks and
 sys.path_importer_cache."""
- if not path:
+ if path is None:
 path = sys.path
 for entry in path:
 try:
diff --git a/Lib/importlib/test/import_/test_path.py b/Lib/importlib/test/import_/test_path.py
--- a/Lib/importlib/test/import_/test_path.py
+++ b/Lib/importlib/test/import_/test_path.py
@@ -42,6 +42,15 @@
 loader = machinery.PathFinder.find_module(module, [path])
 self.assertTrue(loader is importer)
 
+ def test_empty_list(self):
+ # An empty list should not count as asking for sys.path.
+ module = 'module'
+ path = '<test path>'
+ importer = util.mock_modules(module)
+ with util.import_state(path_importer_cache={path: importer},
+ path=[path]):
+ self.assertIsNone(machinery.PathFinder.find_module('module', []))
+
 def test_path_hooks(self):
 # Test that sys.path_hooks is used.
 # Test that sys.path_importer_cache is set.
diff --git a/Lib/importlib/test/test_util.py b/Lib/importlib/test/test_util.py
--- a/Lib/importlib/test/test_util.py
+++ b/Lib/importlib/test/test_util.py
@@ -65,9 +65,23 @@
 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.assertTrue(given is module)
+
+
 class SetPackageTests(unittest.TestCase):
 
-
 """Tests for importlib.util.set_package."""
 
 def verify(self, module, expect):
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,10 @@
 Core and Builtins
 -----------------
 
+- Issue #12599: Be more strict in accepting None compared to a false-like
+ object for importlib.util.module_for_loader and
+ importlib.machinery.PathFinder.
+
 - Issue #14592: Attempting a relative import w/o __package__ or __name__ set in
 globals raises a KeyError.
 
diff --git a/Python/importlib.h b/Python/importlib.h
index 3a03c462530658669296e8e99237c26924ff24b7..392b941b6deaf2be794da994178e0af499f1ba81
GIT binary patch
[stripped]
-- 
Repository URL: http://hg.python.org/cpython
