py: Fix base "detection" for int('0<hexdigit>', 16).

py/parsenumbase.c

@@ -42,7 +42,9 @@ int mp_parse_num_base(const char *str, uint len, int *base) {
         } else if (*base == 0 && (c | 32) == 'b') {
             *base = 2;
         } else {
-            *base = 10;
+            if (*base == 0) {
+                *base = 10;
+            }
             p -= 2;
         }
     } else if (*base == 8 && c == '0') {

tests/basics/int1.py

@@ -37,6 +37,7 @@ print(int('0o123', 0))
 print(int('8388607'))
 print(int('0x123', 16))
 print(int('0X123', 16))
+print(int('0A', 16))
 print(int('0o123', 8))
 print(int('0O123', 8))
 print(int('0123', 8))