Merged revisions 71465 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r71465 | nick.coghlan | 2009-04-11 23:31:31 +1000 (Sat, 11 Apr 2009) | 1 line
Issue 5354: Provide a standardised testing mechanism for doing fresh imports of modules, including the ability to block extension modules in order to test the pure Python fallbacks
........
diff --git a/Lib/test/support.py b/Lib/test/support.py
index 9cd50a0..28823ae 100644
--- a/Lib/test/support.py
+++ b/Lib/test/support.py
@@ -41,22 +41,63 @@
and unexpected skips.
"""
+@contextlib.contextmanager
+def _ignore_deprecated_imports(ignore=True):
+ """Context manager to suppress package and module deprecation
+ warnings when importing them.
+
+ If ignore is False, this context manager has no effect."""
+ if ignore:
+ with warnings.catch_warnings():
+ warnings.filterwarnings("ignore", ".+ (module|package)",
+ DeprecationWarning)
+ yield
+ else:
+ yield
+
+
def import_module(name, deprecated=False):
"""Import and return the module to be tested, raising SkipTest if
it is not available.
If deprecated is True, any module or package deprecation messages
will be suppressed."""
- with warnings.catch_warnings():
- if deprecated:
- warnings.filterwarnings("ignore", ".+ (module|package)",
- DeprecationWarning)
+ with _ignore_deprecated_imports(deprecated):
try:
- module = importlib.import_module(name)
+ return importlib.import_module(name)
except ImportError as msg:
raise unittest.SkipTest(str(msg))
- else:
- return module
+
+
+def import_fresh_module(name, blocked_names=None, deprecated=False):
+ """Imports and returns a module, deliberately bypassing the sys.modules cache
+ and importing a fresh copy of the module. Once the import is complete,
+ the sys.modules cache is restored to its original state.
+
+ Importing of modules named in blocked_names is prevented while the fresh import
+ takes place.
+
+ If deprecated is True, any module or package deprecation messages
+ will be suppressed."""
+ # NOTE: test_heapq and test_warnings include extra sanity checks to make
+ # sure that this utility function is working as expected
+ with _ignore_deprecated_imports(deprecated):
+ if blocked_names is None:
+ blocked_names = ()
+ orig_modules = {}
+ if name in sys.modules:
+ orig_modules[name] = sys.modules[name]
+ del sys.modules[name]
+ try:
+ for blocked in blocked_names:
+ orig_modules[blocked] = sys.modules[blocked]
+ sys.modules[blocked] = 0
+ py_module = importlib.import_module(name)
+ finally:
+ for blocked, module in orig_modules.items():
+ sys.modules[blocked] = module
+ return py_module
+
def get_attribute(obj, name):
"""Get an attribute, raising SkipTest if AttributeError is raised."""
diff --git a/Lib/test/test_heapq.py b/Lib/test/test_heapq.py
index e1e7e9c..bbb22bd 100644
--- a/Lib/test/test_heapq.py
+++ b/Lib/test/test_heapq.py
@@ -7,23 +7,8 @@
# We do a bit of trickery here to be able to test both the C implementation
# and the Python implementation of the module.
-
-# Make it impossible to import the C implementation anymore.
-sys.modules['_heapq'] = 0
-# We must also handle the case that heapq was imported before.
-if 'heapq' in sys.modules:
- del sys.modules['heapq']
-
-# Now we can import the module and get the pure Python implementation.
-import heapq as py_heapq
-
-# Restore everything to normal.
-del sys.modules['_heapq']
-del sys.modules['heapq']
-
-# This is now the module with the C implementation.
import heapq as c_heapq
-
+py_heapq = support.import_fresh_module('heapq', ['_heapq'])
class TestHeap(unittest.TestCase):
module = None
@@ -194,6 +179,13 @@
class TestHeapPython(TestHeap):
module = py_heapq
+ # As an early adopter, we sanity check the
+ # test.support.import_fresh_module utility function
+ def test_pure_python(self):
+ self.assertFalse(sys.modules['heapq'] is self.module)
+ self.assertTrue(hasattr(self.module.heapify, '__code__'))
+
+
class TestHeapC(TestHeap):
module = c_heapq
@@ -219,6 +211,12 @@
self.assertEqual(hsort(data, LT), target)
self.assertRaises(TypeError, data, LE)
+ # As an early adopter, we sanity check the
+ # test.support.import_fresh_module utility function
+ def test_accelerated(self):
+ self.assertTrue(sys.modules['heapq'] is self.module)
+ self.assertFalse(hasattr(self.module.heapify, '__code__'))
+
#==============================================================================
diff --git a/Lib/test/test_warnings.py b/Lib/test/test_warnings.py
index d04c3dd..1f377ad 100644
--- a/Lib/test/test_warnings.py
+++ b/Lib/test/test_warnings.py
@@ -10,18 +10,14 @@
import warnings as original_warnings
-sys.modules['_warnings'] = 0
-del sys.modules['warnings']
-
-import warnings as py_warnings
-
+py_warnings = support.import_fresh_module('warnings', ['_warnings'])
+# XXX (ncoghlan 20090412):
+# Something in Py3k doesn't like sharing the same instance of
+# _warnings between original_warnings and c_warnings
+# Will leave issue 5354 open until I understand why 3.x breaks
+# without the next line, while 2.x doesn't care
del sys.modules['_warnings']
-del sys.modules['warnings']
-
-import warnings as c_warnings
-
-sys.modules['warnings'] = original_warnings
-
+c_warnings = support.import_fresh_module('warnings')
@contextmanager
def warnings_state(module):
@@ -351,9 +347,21 @@
class CWarnTests(BaseTest, WarnTests):
module = c_warnings
+ # As an early adopter, we sanity check the
+ # test.support.import_fresh_module utility function
+ def test_accelerated(self):
+ self.assertFalse(original_warnings is self.module)
+ self.assertFalse(hasattr(self.module.warn, '__code__'))
+
class PyWarnTests(BaseTest, WarnTests):
module = py_warnings
+ # As an early adopter, we sanity check the
+ # test.support.import_fresh_module utility function
+ def test_pure_python(self):
+ self.assertFalse(original_warnings is self.module)
+ self.assertTrue(hasattr(self.module.warn, '__code__'))
+
class WCmdLineTests(unittest.TestCase):