We had the definition of what makes a character "printable" documented in three places, giving two different definitions.
The definition in the comment on `_PyUnicode_IsPrintable` was inverted; correct that.
With that correction, the two definitions turn out to be equivalent -- but to confirm that, you have to go look up, or happen to know, that those are the only five "Other" categories and only three "Separator" categories in the Unicode character database. That makes it hard for the reader to tell whether they really are the same, or if there's some subtle difference in the intended semantics.
Fix that by cutting the C API docs' and the C comment's copies of the subtle details, in favor of referring to the Python-level docs. That ensures it's explicit that these are all meant to agree, and also lets us concentrate improvements to the wording in one place.
Speaking of which, borrow some ideas from the C comment, along with other tweaks, to hopefully add a bit more clarity to that one newly-centralized copy in the docs.
Also add a thorough test that the implementation agrees with this definition.
Author: Greg Price <gnprice@gmail.com>
Co-authored-by: Greg Price <gnprice@gmail.com>
This exposes `_Py_TryIncref` as `PyUnstable_TryIncref()` and the helper
function `_PyObject_SetMaybeWeakref` as `PyUnstable_EnableTryIncRef`.
These are helpers for dealing with unowned references in a safe way,
particularly in the free threading build.
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Stan U. <89152624+StanFromIreland@users.noreply.github.com>
Co-authored-by: Tomas R. <tomas.roun8@gmail.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
The `PyWeakref_IsDead()` function tests if a weak reference is dead
without any side effects. Although you can also detect if a weak
reference is dead using `PyWeakref_GetRef()`, that function returns a
strong reference that must be `Py_DECREF()`'d, which can introduce side
effects if the last reference is concurrently dropped (at least in the
free threading build).
Adds a `use_system_log` config item to enable stdout/stderr redirection for
Apple platforms. This log streaming is then used by a new iOS test runner
script, allowing the display of test suite output at runtime. The iOS test
runner script can be used by any Python project, not just the CPython test
suite.
"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).
