Optimize the subprocess module on FreeBSD using closefrom().
A single close(fd) syscall is cheap, but when sysconf(_SC_OPEN_MAX)
is high, the loop calling close(fd) on each file descriptor can take
several milliseconds.
The workaround on FreeBSD to improve performance was to load and
mount the fdescfs kernel module, but this is not enabled by default.
Initial patch by Ed Maste (emaste), Conrad Meyer (cem), Kyle Evans
(kevans) and Kubilay Kocak (koobs):
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=242274
Added str.removeprefix and str.removesuffix methods and corresponding
bytes, bytearray, and collections.UserString methods to remove affixes
from a string if present. See PEP 616 for a full description.
The constant values of future flags in the __future__ module
is updated in order to prevent collision with compiler flags.
Previously PyCF_ALLOW_TOP_LEVEL_AWAIT was clashing
with CO_FUTURE_DIVISION.
Add random.randbytes() function and random.Random.randbytes()
method to generate random bytes.
Modify secrets.token_bytes() to use SystemRandom.randbytes()
rather than calling directly os.urandom().
Rename also genrand_int32() to genrand_uint32(), since it returns an
unsigned 32-bit integer, not a signed integer.
The _random module is now built with Py_BUILD_CORE_MODULE defined.
Add the encoding in ftplib.FTP and ftplib.FTP_TLS to the
constructor as keyword-only and change the default from "latin-1" to "utf-8"
to follow RFC 2640.
* bpo-39011: Preserve line endings within attributes
Line endings within attributes were previously normalized to "\n" in Py3.7/3.8.
This patch removes that normalization, as line endings which were
replaced by entity numbers should be preserved in original form.
Add the functions PyObject_GC_IsTracked and PyObject_GC_IsFinalized to the public API to allow to query if Python objects are being currently tracked or have been already finalized by the garbage collector respectively.
Add os.waitstatus_to_exitcode() function to convert a wait status to an
exitcode.
Suggest waitstatus_to_exitcode() usage in the documentation when
appropriate.
Use waitstatus_to_exitcode() in:
* multiprocessing, os, subprocess and _bootsubprocess modules;
* test.support.wait_process();
* setup.py: run_command();
* and many tests.
Remove daemon threads from :mod:`concurrent.futures` by adding
an internal `threading._register_atexit()`, which calls registered functions
prior to joining all non-daemon threads. This allows for compatibility
with subinterpreters, which don't support daemon threads.
* Re-add removed classes Suite, slice, Param, AugLoad and AugStore.
* Add docstrings for dummy classes.
* Add docstrings for attribute aliases.
* Set __module__ to "ast" instead of "_ast".
Remove _PyRuntime.getframe hook and remove _PyThreadState_GetFrame
macro which was an alias to _PyRuntime.getframe. They were only
exposed by the internal C API. Remove also PyThreadFrameGetter type.
If a thread different than the main thread gets a signal, the
bytecode evaluation loop is no longer interrupted at each bytecode
instruction to check for pending signals which cannot be handled.
Only the main thread of the main interpreter can handle signals.
Previously, the bytecode evaluation loop was interrupted at each
instruction until the main thread handles signals.
Changes:
* COMPUTE_EVAL_BREAKER() and SIGNAL_PENDING_SIGNALS() no longer set
eval_breaker to 1 if the current thread cannot handle signals.
* take_gil() now always recomputes eval_breaker.
If Py_AddPendingCall() is called in a subinterpreter, the function is
now scheduled to be called from the subinterpreter, rather than being
called from the main interpreter.
Each subinterpreter now has its own list of scheduled calls.
* Move pending and eval_breaker fields from _PyRuntimeState.ceval
to PyInterpreterState.ceval.
* new_interpreter() now calls _PyEval_InitThreads() to create
pending calls lock.
* Fix Py_AddPendingCall() for subinterpreters. It now calls
_PyThreadState_GET() which works in a subinterpreter if the
caller holds the GIL, and only falls back on
PyGILState_GetThisThreadState() if _PyThreadState_GET()
returns NULL.
Extension modules: m_traverse, m_clear and m_free functions of
PyModuleDef are no longer called if the module state was requested
but is not allocated yet. This is the case immediately after the
module is created and before the module is executed (Py_mod_exec
function). More precisely, these functions are not called if m_size is
greater than 0 and the module state (as returned by
PyModule_GetState()) is NULL.
Extension modules without module state (m_size <= 0) are not affected.
Co-Authored-By: Petr Viktorin <encukou@gmail.com>
* Rename _PyInterpreterState_Get() to PyInterpreterState_Get() and
move it the limited C API.
* Add _PyInterpreterState_Get() alias to PyInterpreterState_Get() for
backward compatibility with Python 3.8.
PyInterpreterState.eval_frame function now requires a tstate (Python
thread state) parameter.
Add private functions to the C API to get and set the frame
evaluation function:
* Add tstate parameter to _PyFrameEvalFunction function type.
* Add _PyInterpreterState_GetEvalFrameFunc() and
_PyInterpreterState_SetEvalFrameFunc() functions.
* Add tstate parameter to _PyEval_EvalFrameDefault().
Received email on the docs mailing list to fix a typo from `sys.platlitdir` which doesn't exist to the correct new attribute `sys.platlibdir`
Automerge-Triggered-By: @vstinner
* Remove the slice type.
* Make Slice a kind of the expr type instead of the slice type.
* Replace ExtSlice(slices) with Tuple(slices, Load()).
* Replace Index(value) with a value itself.
All non-terminal nodes in AST for expressions are now of the expr type.
Add --with-platlibdir option to the configure script: name of the
platform-specific library directory, stored in the new sys.platlitdir
attribute. It is used to build the path of platform-specific dynamic
libraries and the path of the standard library.
It is equal to "lib" on most platforms. On Fedora and SuSE, it is
equal to "lib64" on 64-bit systems.
Co-Authored-By: Jan Matějek <jmatejek@suse.com>
Co-Authored-By: Matěj Cepl <mcepl@cepl.eu>
Co-Authored-By: Charalampos Stratakis <cstratak@redhat.com>
The AST "Suite" node is no longer used and it can be removed from the ASDL definition and related structures (compiler, visitors, ...).
Co-Authored-By: Victor Stinner <vstinner@python.org>
Co-authored-by: Brett Cannon <54418+brettcannon@users.noreply.github.com>
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>
Add a section in What's New In Python 3.9 to strongly advice to check
for DeprecationWarning in your Python projects.
Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>
Remove reference to sys.path[0] being absolute path in whatsnew
Co-Authored-By: Kyle Stanley <aeros167@gmail.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Kyle Stanley <aeros167@gmail.com>
* bpo-39648: Expand math.gcd() and math.lcm() to handle multiple arguments.
* Simplify fast path.
* Difine lcm() without arguments returning 1.
* Apply suggestions from code review
Co-Authored-By: Mark Dickinson <dickinsm@gmail.com>
Co-authored-by: Mark Dickinson <dickinsm@gmail.com>
* Hard reset + cherry piciking the changes.
* 📜🤖 Added by blurb_it.
* Added @vstinner News
* Update Misc/NEWS.d/next/Library/2020-02-11-13-01-38.bpo-38691.oND8Sk.rst
Co-Authored-By: Victor Stinner <vstinner@python.org>
* Hard reset to master
* Hard reset to master + latest changes
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
* bpo-39491: Merge PEP 593 (typing.Annotated) support
PEP 593 has been accepted some time ago. I got a green light for merging
this from Till, so I went ahead and combined the code contributed to
typing_extensions[1] and the documentation from the PEP 593 text[2].
My changes were limited to:
* removing code designed for typing_extensions to run on older Python
versions
* removing some irrelevant parts of the PEP text when copying it over as
documentation and otherwise changing few small bits to better serve
the purpose
* changing the get_type_hints signature to match reality (parameter
names)
I wasn't entirely sure how to go about crediting the authors but I used
my best judgment, let me know if something needs changing in this
regard.
[1] 8280de241f/typing_extensions/src_py3/typing_extensions.py
[2] 17710b8798/pep-0593.rst
The os.putenv() and os.unsetenv() functions are now always available.
On non-Windows platforms, Python now requires setenv() and unsetenv()
functions to build.
Remove putenv_dict from posixmodule.c: it's not longer needed.
Deprecate binhex4 and hexbin4 standards. Deprecate the binhex module
and the following binascii functions:
* b2a_hqx(), a2b_hqx()
* rlecode_hqx(), rledecode_hqx()
* crc_hqx()
Remove the buffering parameter of bz2.BZ2File. Since Python 3.0, it
was ignored and using it was emitting a DeprecationWarning. Pass an
open file object to control how the file is opened.
The compresslevel parameter becomes keyword-only.
Remove base64.encodestring() and base64.decodestring(), aliases
deprecated since Python 3.1: use base64.encodebytes() and
base64.decodebytes() instead.
nntplib.NNTP and nntplib.NNTP_SSL now raise a ValueError
if the given timeout for their constructor is zero to
prevent the creation of a non-blocking socket.
poplib.POP3 and poplib.POP3_SSL now raise a ValueError
if the given timeout for their constructor is zero to
prevent the creation of a non-blocking socket.
imaplib.IMAP4 and imaplib.IMAP4_SSL now have an
optional *timeout* parameter for their constructors.
Also, the imaplib.IMAP4.open() method now has an optional *timeout* parameter
with this change. The overridden methods of imaplib.IMAP4_SSL and
imaplib.IMAP4_stream were applied to this change.
Add ast.unparse() as a function in the ast module that can be used to unparse an
ast.AST object and produce a string with code that would produce an equivalent ast.AST
object when parsed.
Remove PyMethod_ClearFreeList() and PyCFunction_ClearFreeList()
functions: the free lists of bound method objects have been removed.
Remove also _PyMethod_Fini() and _PyCFunction_Fini() functions.
This exposes a Linux-specific syscall for sending a signal to a process
identified by a file descriptor rather than a pid.
For simplicity, we don't support the siginfo_t parameter to the syscall. This
parameter allows implementing a pidfd version of rt_sigqueueinfo(2), which
Python also doesn't support.
* "Return true/false" is replaced with "Return ``True``/``False``"
if the function actually returns a bool.
* Fixed formatting of some True and False literals (now in monospace).
* Replaced "True/False" with "true/false" if it can be not only bool.
* Replaced some 1/0 with True/False if it corresponds the code.
* "Returns <bool>" is replaced with "Return <bool>".
CC @encukou
I'm also adding Petr Viktorin as contributor for vectorcall in the "what's new" section.
https://bugs.python.org/issue36974
Automerge-Triggered-By: @encukou
Automerge-Triggered-By: @encukou
Provide Py_EnterRecursiveCall() and Py_LeaveRecursiveCall() as
regular functions for the limited API. Previously, there were defined
as macros, but these macros didn't work with the limited API which
cannot access PyThreadState.recursion_depth field.
Remove _Py_CheckRecursionLimit from the stable ABI.
Add Include/cpython/ceval.h header file.
open(), io.open(), codecs.open() and fileinput.FileInput no longer
accept "U" ("universal newline") in the file mode. This flag was
deprecated since Python 3.3.
This adds a "readlink" method to pathlib.Path objects that calls through
to os.readlink.
https://bugs.python.org/issue30618
Automerge-Triggered-By: @gpshead
* math.perm() and math.comb()
* math.isqrt()
* Add singledispatchmethod()
* itertools.accumulate()
* Optional headers for xmlrpc.client.ServerProxy
* IDLE non-BMP characters
* import collections.abc directly
* @coroutine is deprecated
* pprint.pp()
* New options for object.__reduce__()
* DictReader no longer returns OrderedDicts
* "force" option for logging.basicConfig()
* Fix spelling
* cProfile context manager
* Various markup/grammar fixes from Kyle Stanley.
Other minor fixes as well.
Also, dedup the __reduce__ entry.
* Fix markup
* Fix grammar nits found by MS Word
The `required` argument to `argparse.add_subparsers` was added in #3027. This PR specifies the earliest version of Python where it is available.
https://bugs.python.org/issue26510
Automerge-Triggered-By: @merwok
Py_SetPath() now sets sys.executable to the program full path
(Py_GetProgramFullPath()), rather than to the program name
(Py_GetProgramName()).
Fix also memory leaks in pathconfig_set_from_config().
The socket module now has the socket.send_fds() and socket.recv.fds() functions.
Contributed by Joannah Nanjekye, Shinya Okano (original patch)
and Victor Stinner.
Co-Authored-By: Victor Stinner <vstinner@redhat.com>
* Document `unittest.IsolatedAsyncioTestCase` API
* Add a simple example with respect to order of evaluation of setup and teardown calls.
https://bugs.python.org/issue32972
Automerge-Triggered-By: @asvetlov
* Rename PyThreadState_DeleteCurrent()
to _PyThreadState_DeleteCurrent()
* Move it to the internal C API
Co-Authored-By: Carol Willing <carolcode@willingconsulting.com>
The purpose of the `unicodedata.is_normalized` function is to answer
the question `str == unicodedata.normalized(form, str)` more
efficiently than writing just that, by using the "quick check"
optimization described in the Unicode standard in UAX #15.
However, it turns out the code doesn't implement the full algorithm
from the standard, and as a result we often miss the optimization and
end up having to compute the whole normalized string after all.
Implement the standard's algorithm. This greatly speeds up
`unicodedata.is_normalized` in many cases where our partial variant
of quick-check had been returning MAYBE and the standard algorithm
returns NO.
At a quick test on my desktop, the existing code takes about 4.4 ms/MB
(so 4.4 ns per byte) when the partial quick-check returns MAYBE and it
has to do the slow normalize-and-compare:
$ build.base/python -m timeit -s 'import unicodedata; s = "\uf900"*500000' \
-- 'unicodedata.is_normalized("NFD", s)'
50 loops, best of 5: 4.39 msec per loop
With this patch, it gets the answer instantly (58 ns) on the same 1 MB
string:
$ build.dev/python -m timeit -s 'import unicodedata; s = "\uf900"*500000' \
-- 'unicodedata.is_normalized("NFD", s)'
5000000 loops, best of 5: 58.2 nsec per loop
This restores a small optimization that the original version of this
code had for the `unicodedata.normalize` use case.
With this, that case is actually faster than in master!
$ build.base/python -m timeit -s 'import unicodedata; s = "\u0338"*500000' \
-- 'unicodedata.normalize("NFD", s)'
500 loops, best of 5: 561 usec per loop
$ build.dev/python -m timeit -s 'import unicodedata; s = "\u0338"*500000' \
-- 'unicodedata.normalize("NFD", s)'
500 loops, best of 5: 512 usec per loop
The activation scripts generated by venv were inconsistent in how they changed the shell's prompt. Some used `__VENV_PROMPT__` exclusively, some used `__VENV_PROMPT__` if it was set even though by default `__VENV_PROMPT__` is always set and the fallback matched the default, and one ignored `__VENV_PROMPT__` and used `__VENV_NAME__` instead (and even used a differing format to the default prompt). This change now has all activation scripts use `__VENV_PROMPT__` only and relies on the fact that venv sets that value by default.
The color of the customization is also now set in fish to the blue from the Python logo for as hex color support is built into that shell (much like PowerShell where the built-in green color is used).
bpo-37834: Normalise handling of reparse points on Windows
* ntpath.realpath() and nt.stat() will traverse all supported reparse points (previously was mixed)
* nt.lstat() will let the OS traverse reparse points that are not name surrogates (previously would not traverse any reparse point)
* nt.[l]stat() will only set S_IFLNK for symlinks (previous behaviour)
* nt.readlink() will read destinations for symlinks and junction points only
bpo-1311: os.path.exists('nul') now returns True on Windows
* nt.stat('nul').st_mode is now S_IFCHR (previously was an error)
DeprecationWarning will continue to be emitted for invalid escape
sequences in string and bytes literals just as it did in 3.7.
SyntaxWarning may be emitted in the future. But per mailing list
discussion, we don't yet know when because we haven't settled on how to
do so in a non-disruptive manner.
(Applies 4c5b6bac24 to the master branch).
(This is https://github.com/python/cpython/pull/15142 for master/3.9)
https://bugs.python.org/issue32912
Automerge-Triggered-By: @gpshead
Imports now raise `TypeError` instead of `ValueError` for relative import failures. This makes things consistent between `builtins.__import__` and `importlib.__import__` as well as using a more natural import for the failure.
https://bugs.python.org/issue37444
Automerge-Triggered-By: @brettcannon
Deprecate the parser module and add a deprecation warning triggered on import and a warning block in the documentation.
https://bugs.python.org/issue37268
Automerge-Triggered-By: @pablogsal
Remove the undocumented sys.callstats() function. Since Python 3.7,
it was deprecated and always returned None. It required a special
build option CALL_PROFILE which was already removed in Python 3.7.
The os.getcwdb() function now uses the UTF-8 encoding on Windows,
rather than the ANSI code page: see PEP 529 for the rationale. The
function is no longer deprecated on Windows.
os.getcwd() and os.getcwdb() now detect integer overflow on memory
allocations. On Unix, these functions properly report MemoryError on
memory allocation failure.
In development mode and in debug build, encoding and errors arguments
are now checked on string encoding and decoding operations. Examples:
open(), str.encode() and bytes.decode().
By default, for best performances, the errors argument is only
checked at the first encoding/decoding error, and the encoding
argument is sometimes ignored for empty strings.
Python now gets the absolute path of the script filename specified on
the command line (ex: "python3 script.py"): the __file__ attribute of
the __main__ module, sys.argv[0] and sys.path[0] become an absolute
path, rather than a relative path.
* Add _Py_isabs() and _Py_abspath() functions.
* _PyConfig_Read() now tries to get the absolute path of
run_filename, but keeps the relative path if _Py_abspath() fails.
* Reimplement os._getfullpathname() using _Py_abspath().
* Use _Py_isabs() in getpath.c.
Remove sys.getcheckinterval() and sys.setcheckinterval() functions.
They were deprecated since Python 3.2. Use sys.getswitchinterval()
and sys.setswitchinterval() instead.
Remove also check_interval field of the PyInterpreterState structure.
* Rename PyImport_Cleanup() to _PyImport_Cleanup() and move it to the
internal C API. Add 'tstate' parameters.
* Remove documentation of _PyImport_Init(), PyImport_Cleanup(),
_PyImport_Fini(). All three were documented as "For internal use
only.".
aifc.openfp() alias to aifc.open(), sunau.openfp() alias to
sunau.open(), and wave.openfp() alias to wave.open() have been
removed. They were deprecated since Python 3.7.
Add a new public PyObject_CallNoArgs() function to the C API: call a
callable Python object without any arguments.
It is the most efficient way to call a callback without any argument.
On x86-64, for example, PyObject_CallFunctionObjArgs(func, NULL)
allocates 960 bytes on the stack per call, whereas
PyObject_CallNoArgs(func) only allocates 624 bytes per call.
It is excluded from stable ABI 3.8.
Replace private _PyObject_CallNoArg() with public
PyObject_CallNoArgs() in C extensions: _asyncio, _datetime,
_elementtree, _pickle, _tkinter and readline.