gh-116307: Create a new import helper 'isolated modules' and use that instead of 'Clean Import' to ensure that tests from importlib_resources don't leave modules in sys.modules.
Enforcing (optionally) the restriction set by PEP 489 makes sense. Furthermore, this sets the stage for a potential restriction related to a per-interpreter GIL.
This change includes the following:
* add tests for extension module subinterpreter compatibility
* add _PyInterpreterConfig.check_multi_interp_extensions
* add Py_RTFLAGS_MULTI_INTERP_EXTENSIONS
* add _PyImport_CheckSubinterpIncompatibleExtensionAllowed()
* fail iff the module does not implement multi-phase init and the current interpreter is configured to check
https://github.com/python/cpython/issues/98627
test_tools.test_sundry() now uses an unittest mock to prevent the
logging module to register a real "atfork" function which kept the
logging module dictionary alive. So the logging module can be
properly unloaded. Previously, the logging module was loaded before
test_sundry(), but it's no longer the case since recent test_tools
sub-tests removals.
In [Lib/test/support/import_helper.py](https://github.com/python/cpython/blob/master/Lib/test/support/import_helper.py), the function `make_legacy_pyc` makes a call to `os.rename` which can fail when the source and target live on different devices. This happens (for example) when `PYTHONPYCACHEPREFIX` is set to a directory anywhere on disk, while a ramdisk is mounted on `/tmp` (the latter of which is the default on various Linux distros). Replacing `os.rename` with `shutil.move` fixes this.
Automerge-Triggered-By: GH:brettcannon
* Work correctly if an additional fresh module imports other
additional fresh module which imports a blocked module.
* Raises ImportError if the specified module cannot be imported
while all additional fresh modules are successfully imported.
* Support blocking packages.
* Always restore the import state of fresh and blocked modules
and their submodules.
* Fix test_decimal and test_xml_etree which depended on an undesired
side effect of import_fresh_module().
Currently we freeze several modules into the runtime. For each of these modules it is essential to bootstrapping the runtime that they be frozen. Any other stdlib module that we later freeze into the runtime is not essential. We can just as well import from the .py file. This PR lets users explicitly choose which should be used, with the new "-X frozen_modules=[on|off]" CLI flag. The default is "off" for now.
https://bugs.python.org/issue45020
Eric Snow
Jason R. Coombs
Nikita Sobolev
Victor Stinner
Jason Wilkes
Serhiy Storchaka
Hai Shi