"Generally, mixed-mode arithmetic combining real and complex variables should
be performed directly, not by first coercing the real to complex, lest the sign
of zero be rendered uninformative; the same goes for combinations of pure
imaginary quantities with complex variables." (c) Kahan, W: Branch cuts for
complex elementary functions.
This patch implements mixed-mode arithmetic rules, combining real and
complex variables as specified by C standards since C99 (in particular,
there is no special version for the true division with real lhs
operand). Most C compilers implementing C99+ Annex G have only these
special rules (without support for imaginary type, which is going to be
deprecated in C2y).
* Setting the __module__ attribute for a class now removes the
__firstlineno__ item from the type's dict.
* The _collections_abc and _pydecimal modules now completely replace the
collections.abc and decimal modules after importing them. This
allows to get the source of classes and functions defined in these
modules.
* inspect.findsource() now checks whether the first line number for a
class is out of bound.
* Use compensated summation for complex sums with floating-point items.
This amends #121176.
* sum() specializations for floats and complexes now use
PyLong_AsDouble() instead of PyLong_AsLongAndOverflow() and
compensated summation as well.
It was raised in two cases:
* in the import statement when looking up __import__
* in pickling some builtin type when looking up built-ins iter, getattr, etc.
If the input prompt to the builtin input function on terminal has any null
character, then raise ValueError instead of silently truncating it.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
test_builtin and test_socketserver no longer use signal.alarm() to
implement a watchdog with a hardcoded timeout (2 and 60 seconds).
Python test runner regrtest has two watchdogs: faulthandler and
timeout on running worker processes. Tests using short hardcoded
timeout can fail on slowest buildbots just because the timeout is too
short.
This is the implementation of PEP683
Motivation:
The PR introduces the ability to immortalize instances in CPython which bypasses reference counting. Tagging objects as immortal allows up to skip certain operations when we know that the object will be around for the entire execution of the runtime.
Note that this by itself will bring a performance regression to the runtime due to the extra reference count checks. However, this brings the ability of having truly immutable objects that are useful in other contexts such as immutable data sharing between sub-interpreters.
Add a closure keyword-only parameter to exec(). It can only be specified when exec-ing a code object that uses free variables. When specified, it must be a tuple, with exactly the number of cell variables referenced by the code object. closure has a default value of None, and it must be None if the code object doesn't refer to any free variables.
Use common error message for non-string attribute name in the builtin
functions getattr and hasattr.
The special check no longer needed since Python 3.0.
Skip test_builtin PTY tests on non-ASCII characters if the readline
module is loaded. The readline module changes input() behavior, but
test_builtin is not intented to test the readline module.
When the readline module is loaded, PyOS_Readline() uses the readline
implementation. In some cases, the Python readline callback
rlhandler() is called by readline with a string without non-ASCII
characters.
Several built-in and standard library types now ensure that their internal result tuples are always tracked by the garbage collector:
- collections.OrderedDict.items
- dict.items
- enumerate
- functools.reduce
- itertools.combinations
- itertools.combinations_with_replacement
- itertools.permutations
- itertools.product
- itertools.zip_longest
- zip
Previously, they could have become untracked by a prior garbage collection.