py/objint: Allow int() to parse anything with the buffer protocol.

This generalises and simplifies the code and follows CPython behaviour.

See similar change for floats in a07fc5b.

Signed-off-by: Damien George <damien@micropython.org>

py/objint.c

@@ -49,14 +49,13 @@ STATIC mp_obj_t mp_obj_int_make_new(const mp_obj_type_t *type_in, size_t n_args,
             return MP_OBJ_NEW_SMALL_INT(0);
 
         case 1: {
+            mp_buffer_info_t bufinfo;
             mp_obj_t o = mp_unary_op(MP_UNARY_OP_INT_MAYBE, args[0]);
             if (o != MP_OBJ_NULL) {
                 return o;
-            } else if (mp_obj_is_str_or_bytes(args[0])) {
-                // a string, parse it
-                size_t l;
-                const char *s = mp_obj_str_get_data(args[0], &l);
-                return mp_parse_num_integer(s, l, 0, NULL);
+            } else if (mp_get_buffer(args[0], &bufinfo, MP_BUFFER_READ)) {
+                // a textual representation, parse it
+                return mp_parse_num_integer(bufinfo.buf, bufinfo.len, 0, NULL);
             #if MICROPY_PY_BUILTINS_FLOAT
             } else if (mp_obj_is_float(args[0])) {
                 return mp_obj_new_int_from_float(mp_obj_float_get(args[0]));

tests/basics/int_parse.py

@@ -0,0 +1,12 @@
+# Test parsing ints.
+
+try:
+    bytearray
+    memoryview
+except NameError:
+    print("SKIP")
+    raise SystemExit
+
+print(int(b"123"))
+print(int(bytearray(b"123")))
+print(int(memoryview(b"123")))