py/objarray: Detect bytearray(str) without an encoding.

This prevents a very subtle bug caused by writing e.g. `bytearray('\xfd')`
which gives you `(0xc3, 0xbd)`.

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

py/objarray.c

@@ -192,6 +192,14 @@ STATIC mp_obj_t bytearray_make_new(const mp_obj_type_t *type_in, size_t n_args,
         return MP_OBJ_FROM_PTR(o);
     } else {
         // 1 arg: construct the bytearray from that
+        if (mp_obj_is_str(args[0]) && n_args == 1) {
+            #if MICROPY_ERROR_REPORTING <= MICROPY_ERROR_REPORTING_TERSE
+            // Match bytes_make_new.
+            mp_raise_TypeError(MP_ERROR_TEXT("wrong number of arguments"));
+            #else
+            mp_raise_TypeError(MP_ERROR_TEXT("string argument without an encoding"));
+            #endif
+        }
         return array_construct(BYTEARRAY_TYPECODE, args[0]);
     }
 }