Issue #14744: Use the new _PyUnicodeWriter internal API to speed up str%args and str.format(args)
* 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.
diff --git a/Include/longobject.h b/Include/longobject.h
index c58ddf4..d741f1b 100644
--- a/Include/longobject.h
+++ b/Include/longobject.h
@@ -151,14 +151,22 @@
/* _PyLong_Format: Convert the long to a string object with given base,
appending a base prefix of 0[box] if base is 2, 8 or 16. */
-PyAPI_FUNC(PyObject *) _PyLong_Format(PyObject *aa, int base);
+PyAPI_FUNC(PyObject *) _PyLong_Format(PyObject *obj, int base);
+
+PyAPI_FUNC(int) _PyLong_FormatWriter(
+ _PyUnicodeWriter *writer,
+ PyObject *obj,
+ int base,
+ int alternate);
/* Format the object based on the format_spec, as defined in PEP 3101
(Advanced String Formatting). */
-PyAPI_FUNC(PyObject *) _PyLong_FormatAdvanced(PyObject *obj,
- PyObject *format_spec,
- Py_ssize_t start,
- Py_ssize_t end);
+PyAPI_FUNC(int) _PyLong_FormatAdvancedWriter(
+ _PyUnicodeWriter *writer,
+ PyObject *obj,
+ PyObject *format_spec,
+ Py_ssize_t start,
+ Py_ssize_t end);
#endif /* Py_LIMITED_API */
/* These aren't really part of the long object, but they're handy. The