Add Modules/_testcapi/util.h header (GH-108774)
It contains common macros used in C API tests.
(cherry picked from commit 0e01fac315)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
* Support for conversion specifiers o (octal) and X (uppercase hexadecimal).
* Support for length modifiers j (intmax_t) and t (ptrdiff_t).
* Length modifiers are now applied to all integer conversions.
* Support for wchar_t C strings (%ls and %lV).
* Support for variable width and precision (*).
* Support for flag - (left alignment).
- Move PyUnicode tests to a separate file
- Add some more tests for PyUnicode_FromFormat
Co-authored-by: philg314 <110174000+philg314@users.noreply.github.com>