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.
In a subinterpreter, spawning a daemon thread now raises an
exception. Daemon threads were never supported in subinterpreters.
Previously, the subinterpreter finalization crashed with a Pyton
fatal error if a daemon thread was still running.
* Add _thread._is_main_interpreter()
* threading.Thread.start() now raises RuntimeError if the thread is a
daemon thread and the method is called from a subinterpreter.
* The _thread module now uses Argument Clinic for the new function.
* Use textwrap.dedent() in test_threading.SubinterpThreadingTests
* Update PyCompilerFlags structure documentation.
* Document the new cf_feature_version field in the Changes in the C
API section of the What's New in Python 3.8 doc.
It is now allowed to add new fields at the end of the PyTypeObject struct without having to allocate a dedicated compatibility flag in tp_flags.
This will reduce the risk of running out of bits in the 32-bit tp_flags value.
* bpo-26836: Add os.memfd_create()
* Use the glibc wrapper for memfd_create()
Co-Authored-By: Christian Heimes <christian@python.org>
* Fix deletions caused by autoreconf.
* Use MFD_CLOEXEC as the default value for *flags*.
* Add memset_s to configure.ac.
* Revert memset_s changes.
* Apply the requested changes.
* Tweak the docs.
It has been documented as deprecated and to be removed in 3.8;
From a comment on another thread – which I can't find ; leave get_coro_wrapper() for now, but always return `None`.
https://bugs.python.org/issue36933
Add a new threading.excepthook() function which handles uncaught
Thread.run() exception. It can be overridden to control how uncaught
exceptions are handled.
threading.ExceptHookArgs is not documented on purpose: it should not
be used directly.
* threading.excepthook() and threading.ExceptHookArgs.
* Add _PyErr_Display(): similar to PyErr_Display(), but accept a
'file' parameter.
* Add _thread._excepthook(): C implementation of the exception hook
calling _PyErr_Display().
* Add _thread._ExceptHookArgs: structseq type.
* Add threading._invoke_excepthook_wrapper() which handles the gory
details to ensure that everything remains alive during Python
shutdown.
* Add unit tests.
It is also possible to link against a library or executable with a
statically linked libpython, but not both with the same DLL. In fact
building a statically linked python is currently broken on Cygwin
for other (related) reasons.
The same problem applies to other POSIX-like layers over Windows
(MinGW, MSYS) but Python's build system does not seem to attempt
to support those platforms at the moment.
In development (-X dev) mode and in a debug build, IOBase finalizer
of the _pyio module now logs the exception if the close() method
fails. The exception is ignored silently by default in release build.
test_io: test_error_through_destructor() now uses
support.catch_unraisable_exception() rather than capturing stderr.
To embed Python into an application, a new --embed option must be
passed to "python3-config --libs --embed" to get "-lpython3.8" (link
the application to libpython). To support both 3.8 and older, try
"python3-config --libs --embed" first and fallback to "python3-config
--libs" (without --embed) if the previous command fails.
Add a pkg-config "python-3.8-embed" module to embed Python into an
application: "pkg-config python-3.8-embed --libs" includes
"-lpython3.8". To support both 3.8 and older, try "pkg-config
python-X.Y-embed --libs" first and fallback to "pkg-config python-X.Y
--libs" (without --embed) if the previous command fails (replace
"X.Y" with the Python version).
On the other hand, "pkg-config python3.8 --libs" no longer contains
"-lpython3.8". C extensions must not be linked to libpython (except
on Android, case handled by the script); this change is backward
incompatible on purpose.
"make install" now also installs "python-3.8-embed.pc".
Add new sys.unraisablehook() function which can be overridden to
control how "unraisable exceptions" are handled. It is called when an
exception has occurred but there is no way for Python to handle it.
For example, when a destructor raises an exception or during garbage
collection (gc.collect()).
Changes:
* Add an internal UnraisableHookArgs type used to pass arguments to
sys.unraisablehook.
* Add _PyErr_WriteUnraisableDefaultHook().
* The default hook now ignores exception on writing the traceback.
* test_sys now uses unittest.main() to automatically discover tests:
remove test_main().
* Add _PyErr_Init().
* Fix PyErr_WriteUnraisable(): hold a strong reference to sys.stderr
while using it
* Add math.isqrt function computing the integer square root.
* Code cleanup: remove redundant comments, rename some variables.
* Tighten up code a bit more; use Py_XDECREF to simplify error handling.
* Update Modules/mathmodule.c
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Update Modules/mathmodule.c
Use real argument clinic type instead of an alias
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Add proof sketch
* Updates from review.
* Correct and expand documentation.
* Fix bad reference handling on error; make some variables block-local; other tidying.
* Style and consistency fixes.
* Add missing error check; don't try to DECREF a NULL a
* Simplify some error returns.
* Another two test cases:
- clarify that floats are rejected even if they happen to be
squares of small integers
- TypeError beats ValueError for a negative float
* Documentation and markup improvements; thanks Serhiy for the suggestions!
* Cleaner Misc/NEWS entry wording.
* Clean up (with one fix) to the algorithm explanation and proof.
Plistlib currently throws an exception when asked to decode a valid
.plist file that was generated by Apple's NSKeyedArchiver. Specifically,
this is caused by a byte 0x80 (signifying a UID) not being understood.
This fixes the problem by enabling the binary plist reader and writer
to read and write plistlib.UID objects.
Remove the PyEval_ReInitThreads() function from the Python C API.
It should not be called explicitly: use PyOS_AfterFork_Child()
instead.
Rename PyEval_ReInitThreads() to _PyEval_ReInitThreads() and add a
'runtime' parameter.
If a "=" is specified a the end of an f-string expression, the f-string will evaluate to the text of the expression, followed by '=', followed by the repr of the value of the expression.
* Implement C14N 2.0 as a new canonicalize() function in ElementTree.
Missing features:
- prefix renaming in XPath expressions (tag and attribute text is supported)
- preservation of original prefixes given redundant namespace declarations
PyEval_AcquireLock() and PyEval_AcquireThread() now
terminate the current thread if called while the interpreter is
finalizing, making them consistent with PyEval_RestoreThread(),
Py_END_ALLOW_THREADS, and PyGILState_Ensure().
On Unix, C extensions are no longer linked to libpython.
It is now possible to load a C extension built using a shared library
Python with a statically linked Python.
When Python is embedded, libpython must not be loaded with
RTLD_LOCAL, but RTLD_GLOBAL instead. Previously, using RTLD_LOCAL, it
was already not possible to load C extensions which were not linked
to libpython, like C extensions of the standard library built by the
"*shared*" section of Modules/Setup.
distutils, python-config and python-config.py have been modified.
Document that subprocess.Popen no longer raise an exception on error
like missing program on very specific platforms when using
os.posix_spawn() is used.
The imap.IMAP4.logout() method no longer ignores silently arbitrary
exceptions.
Changes:
* The IMAP4.logout() method now expects a "BYE" untagged response,
rather than relying on _check_bye() which raises a self.abort()
exception.
* IMAP4.__exit__() now does nothing if the client already logged out.
* Add more debug info if test_logout() tests fail.
On AIX, sys.platform doesn't contain the major version anymore.
Always return 'aix', instead of 'aix3' .. 'aix7'. Since
older Python versions include the version number, it is recommended to
always use sys.platform.startswith('aix').
Deprecated passing the following arguments as keyword arguments:
- "func" in functools.partialmethod(), weakref.finalize(),
profile.Profile.runcall(), cProfile.Profile.runcall(),
bdb.Bdb.runcall(), trace.Trace.runfunc() and
curses.wrapper().
- "function" in unittest.addModuleCleanup() and
unittest.TestCase.addCleanup().
- "fn" in the submit() method of concurrent.futures.ThreadPoolExecutor
and concurrent.futures.ProcessPoolExecutor.
- "callback" in contextlib.ExitStack.callback(),
contextlib.AsyncExitStack.callback() and
contextlib.AsyncExitStack.push_async_callback().
- "c" and "typeid" in the create() method of multiprocessing.managers.Server
and multiprocessing.managers.SharedMemoryServer.
- "obj" in weakref.finalize().
Also allowed to pass arbitrary keyword arguments (even "self" and "func")
if the above arguments are passed as positional argument.