This is more complicated than it should be because we need to preserve the
useful mtime-based regeneration feature that lib2to3.pgen2.driver.load_grammar
has. We only look for the pickled grammar file with pkgutil.get_data and only if
the source file does not exist.
* _Py_InitializeCore() doesn't call _PyMem_SetupAllocators() anymore
if the PYTHONMALLOC environment variable is not set.
* pymain_cmdline() now sets the allocator to the default, instead of
setting the allocator in subfunctions.
* Py_SetStandardStreamEncoding() now calls
_PyMem_SetDefaultAllocator() to get a known allocator, to be able
to release the memory with the same allocator.
Even though Python marks any handles it opens as non-inheritable there
is still a race when using `subprocess.Popen` since creating a process
with redirected stdio requires temporarily creating inheritable handles.
By implementing support for `subprocess.Popen(close_fds=True)` we fix
this race.
In order to implement this we use PROC_THREAD_ATTRIBUTE_HANDLE_LIST
which is available since Windows Vista. Which allows to pass an explicit
list of handles to inherit when creating a process.
This commit also adds `STARTUPINFO.lpAttributeList["handle_list"]`
which can be used to control PROC_THREAD_ATTRIBUTE_HANDLE_LIST
directly.
Exactly which locale requests will end up giving
you the "C" locale is actually platform dependent.
A blank locale and "POSIX" will translate to "C"
on most Linux distros, but may not do so on other platforms, so this adjusts the way the tests are structured to better account for that.
This is an initial step towards fixing the current
test failure on Cygwin (hence the issue reference)
It no longer spends much time doing complex calculations and no
longer consumes much memory for creating large constants that will
be dropped later.
This fixes also bpo-21074.
bpo-32329, bpo-32030:
* The -R option now turns on hash randomization when the
PYTHONHASHSEED environment variable is set to 0 Previously, the
option was ignored.
* sys.flags.hash_randomization is now properly set to 0 when hash
randomization is turned off by PYTHONHASHSEED=0.
* _PyCoreConfig_ReadEnv() now reads the PYTHONHASHSEED environment
variable. _Py_HashRandomization_Init() now only apply the
configuration, it doesn't read PYTHONHASHSEED anymore.
asyncio.get_event_loop(), and, subsequently asyncio._get_running_loop()
are one of the most frequently executed functions in asyncio. They also
can't be sped up by third-party event loops like uvloop.
When implemented in C they become 4x faster.
* Add -X utf8 command line option, PYTHONUTF8 environment variable
and a new sys.flags.utf8_mode flag.
* If the LC_CTYPE locale is "C" at startup: enable automatically the
UTF-8 mode.
* Add _winapi.GetACP(). encodings._alias_mbcs() now calls
_winapi.GetACP() to get the ANSI code page
* locale.getpreferredencoding() now returns 'UTF-8' in the UTF-8
mode. As a side effect, open() now uses the UTF-8 encoding by
default in this mode.
* Py_DecodeLocale() and Py_EncodeLocale() now use the UTF-8 encoding
in the UTF-8 Mode.
* Update subprocess._args_from_interpreter_flags() to handle -X utf8
* Skip some tests relying on the current locale if the UTF-8 mode is
enabled.
* Add test_utf8mode.py.
* _Py_DecodeUTF8_surrogateescape() gets a new optional parameter to
return also the length (number of wide characters).
* pymain_get_global_config() and pymain_set_global_config() now
always copy flag values, rather than only copying if the new value
is greater than the old value.
Rather than supporting dev mode directly in the warnings module, this
instead adjusts the initialisation code to add an extra 'default'
entry to sys.warnoptions when dev mode is enabled.
This ensures that dev mode behaves *exactly* as if `-Wdefault` had
been passed on the command line, including in the way it interacts
with `sys.warnoptions`, and with other command line flags like `-bb`.
Fix also bpo-20361: have -b & -bb options take precedence over any
other warnings options.
Patch written by Nick Coghlan, with minor modifications of Victor Stinner.