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."""