* Simplify the code: replace 4 steps with one unique step using the
_PyUnicodeWriter API. PyUnicode_Format() has the same design. It avoids to
store intermediate results which require to allocate an array of pointers on
the heap.
* Use the _PyUnicodeWriter API for speed (and its convinient API):
overallocate the buffer to reduce the number of "realloc()"
* Implement "width" and "precision" in Python, don't rely on sprintf(). It
avoids to need of a temporary buffer allocated on the heap: only use a small
buffer allocated in the stack.
* Add _PyUnicodeWriter_WriteCstr() function
* Split PyUnicode_FromFormatV() into two functions: add
unicode_fromformat_arg().
* Inline parse_format_flags(): the format of an argument is now only parsed
once, it's no more needed to have a subfunction.
* Optimize PyUnicode_FromFormatV() for characters between two "%" arguments:
search the next "%" and copy the substring in one chunk, instead of copying
character per character.
* Formatting string, int, float and complex use the _PyUnicodeWriter API. It
avoids a temporary buffer in most cases.
* Add _PyUnicodeWriter_WriteStr() to restore the PyAccu optimization: just
keep a reference to the string if the output is only composed of one string
* Disable overallocation when formatting the last argument of str%args and
str.format(args)
* Overallocation allocates at least 100 characters: add min_length attribute
to the _PyUnicodeWriter structure
* Add new private functions: _PyUnicode_FastCopyCharacters(),
_PyUnicode_FastFill() and _PyUnicode_FromASCII()
The speed up is around 20% in average.
* Decode thousands separator and decimal point using PyUnicode_DecodeLocale()
(from the locale encoding), instead of decoding them implicitly from latin1
* Remove _PyUnicode_InsertThousandsGroupingLocale(), it was not used
* Change _PyUnicode_InsertThousandsGrouping() API to return the maximum
character if unicode is NULL
* Replace MIN/MAX macros by Py_MIN/Py_MAX
* stringlib/undef.h undefines STRINGLIB_IS_UNICODE
* stringlib/localeutil.h only supports Unicode
* PyUnicode_DecodeLocaleAndSize() and PyUnicode_DecodeLocale() decode a string
from the current locale encoding
* _Py_char2wchar() writes an "error code" in the size argument to indicate
if the function failed because of memory allocation failure or because of a
decoding error. The function doesn't write the error message directly to
stderr.
* Fix time.strftime() (if wcsftime() is missing): decode strftime() result
from the current locale encoding, not from the filesystem encoding.
A Unicode string can now be a PyASCIIObject, PyCompactUnicodeObject or
PyUnicodeObject. Aliasing a PyASCIIObject* or PyCompactUnicodeObject* to
PyUnicodeObject* is wrong
Use PyUnicode_IS_ASCII instead of PyUnicode_IS_COMPACT_ASCII, so the following
test can be removed:
PyUnicode_DATA(op) == (((PyCompactUnicodeObject *)(op))->utf8)
