Currently custom modules (the array set on PyImport_FrozenModules) replace all the frozen stdlib modules. That can be problematic and is unlikely to be what the user wants. This change treats the custom frozen modules as additions instead. They take precedence over all other frozen modules except for those needed to bootstrap the import system. If the "code" field of an entry in the custom array is NULL then that frozen module is treated as disabled, which allows a custom entry to disable a frozen stdlib module.
This change allows us to get rid of is_essential_frozen_module() and simplifies the logic for which frozen modules should be ignored.
https://bugs.python.org/issue45395
The list of PEPs at the top of the documentation for the ``typing`` module has
become too long to be readable. This PR proposes presenting this
information in a more structured and readable way by adding a new "relevant
PEPs" section to the ``typing`` docs.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
(original patch by eryksun)
Correctly hand various failure modes when resizing an mmap on Windows:
* Resizing a pagefile-backed mmap now creates a new mmap and copies data
* Attempting to resize when another mapping is held on the same file raises an OSError
* Attempting to resize a nametagged mmap raises an OSError if another mapping is held with the same nametag
Rename namespace package __loader__ class to be public.
Make the old name, i.e. _NamespaceLoader, an alias for the public name, for backward compatibility.
Added non parallel-safe :func:`~contextlib.chdir` context manager to change
the current working directory and then restore it on exit. Simple wrapper
around :func:`~os.chdir`.
Signed-off-by: Filipe Laíns <lains@riseup.net>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
I considered only falling back when both were 0, but that still seems
wrong, and the highly popular rich[1] library does it this way, so I
thought we should probably inherit that behavior.
[1] https://github.com/willmcgugan/rich
Signed-off-by: Filipe Laíns <lains@riseup.net>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
* bpo-45516: add protocol description to the Traversable documentation
Signed-off-by: Filipe Laíns <lains@riseup.net>
* Update Doc/library/importlib.rst
Co-authored-by: Jason R. Coombs <jaraco@jaraco.com>
* Update Lib/importlib/abc.py
* Update Doc/library/importlib.rst
Co-authored-by: Jason R. Coombs <jaraco@jaraco.com>
Co-authored-by: Jason R. Coombs <jaraco@jaraco.com>
This is true of all dictionaries in Python, but this one tends to
catch people off guard as they don't realize when sys.modules might
change out from underneath them as a hidden side effect of their
code. Copying it first avoids the RuntimeError. An example when
this happens in single threaded code are codecs being loaded which
are an implicit time of use import that most need not think about.
It took me longer than I expected to figure out why a random class
I dealt with didn't support weak references. I believe this addition
will make the __slots__/weakref interaction more discoverable to people
having troubles with this. (Before this patch __slots__ was not
mentioned in weakref documentation even once).
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
* Support HTTP response status code 308 in urllib.
HTTP response status code 308 is defined in https://tools.ietf.org/html/rfc7538 to be the permanent redirect variant of 307 (temporary redirect).
* Update documentation to include http_error_308()
* Add blurb for bpo-40321 fix
Co-authored-by: Roland Crosby <roland@rolandcrosby.com>
