Fix compilation with Python 3.12

Python 3.12 finally removed PyUnicode_GET_SIZE, which we were still
using unaware of its deprecation. This commit defines a macro that uses
PyUnicode_GET_SIZE for Python 2.7, or PyUnicode_GET_LENGTH (the function
we should be using) for Python 3.

This addresses the original issue reported in #98.

Signed-off-by: Rodrigo Tobar <[email protected]>

Author: rtobar

ijson/backends/yajl2_c/parse_basecoro.c

@@ -13,6 +13,11 @@
 #include "kvitems_basecoro.h"
 #include "parse_basecoro.h"
 
+#if PY_MAJOR_VERSION >= 3
+#define ijson_unicode_length PyUnicode_GET_LENGTH
+#else
+#define ijson_unicode_length PyUnicode_GET_SIZE
+#endif
 
 /*
  * __init__, destructor, __iter__ and __next__
@@ -90,7 +95,7 @@ PyObject* parse_basecoro_send_impl(PyObject *self, PyObject *event, PyObject *va
 		PyObject *last_path;
 		N_N(last_path = PySequence_GetItem(gen->path, npaths - 1));
 
-		if (PyUnicode_GET_SIZE(last_path) > 0) {
+		if (ijson_unicode_length(last_path) > 0) {
 			PyObject *new_path;
 			CONCAT(new_path, last_path, dotitem);
 			N_M1(PyList_Append(gen->path, new_path));