Close #14648: Compute correctly maxchar in str.format() for substrin
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 7e73bc2..2b90cfa 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -1957,6 +1957,37 @@
}
}
+Py_UCS4
+_PyUnicode_FindMaxChar(PyObject *unicode, Py_ssize_t start, Py_ssize_t end)
+{
+ enum PyUnicode_Kind kind;
+ void *startptr, *endptr;
+
+ assert(PyUnicode_IS_READY(unicode));
+ assert(0 <= start);
+ assert(end <= PyUnicode_GET_LENGTH(unicode));
+ assert(start <= end);
+
+ if (start == 0 && end == PyUnicode_GET_LENGTH(unicode))
+ return PyUnicode_MAX_CHAR_VALUE(unicode);
+
+ if (start == end)
+ return 127;
+
+ kind = PyUnicode_KIND(unicode);
+ startptr = PyUnicode_DATA(unicode);
+ endptr = (char*)startptr + end * kind;
+ if (start)
+ startptr = (char*)startptr + start * kind;
+ switch(kind)
+ {
+ case PyUnicode_1BYTE_KIND: return ucs1lib_find_max_char(startptr, endptr);
+ case PyUnicode_2BYTE_KIND: return ucs2lib_find_max_char(startptr, endptr);
+ default:
+ case PyUnicode_4BYTE_KIND: return ucs4lib_find_max_char(startptr, endptr);
+ }
+}
+
/* Ensure that a string uses the most efficient storage, if it is not the
case: create a new string with of the right kind. Write NULL into *p_unicode
on error. */