py/obj: Merge getiter and iternext mp_obj_type_t slots.

The goal here is to remove a slot (making way to turn make_new into a slot)
as well as reduce code size by the ~40 references to mp_identity_getiter
and mp_stream_unbuffered_iter.

This introduces two new type flags:
- MP_TYPE_FLAG_ITER_IS_ITERNEXT: This means that the "iter" slot in the
  type is "iternext", and should use the identity getiter.
- MP_TYPE_FLAG_ITER_IS_CUSTOM: This means that the "iter" slot is a pointer
  to a mp_getiter_iternext_custom_t instance, which then defines both
  getiter and iternext.

And a third flag that is the OR of both, MP_TYPE_FLAG_ITER_IS_STREAM: This
means that the type should use the identity getiter, and
mp_stream_unbuffered_iter as iternext.

Finally, MP_TYPE_FLAG_ITER_IS_GETITER is defined as a no-op flag to give
the default case where "iter" is "getiter".

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

1 files changed, 2 insertions, 3 deletions

diff --git a/py/objenumerate.c b/py/objenumerate.c
index f4f4ff6ae1..eea9e3e381 100644
--- a/py/objenumerate.c
+++ b/py/objenumerate.c
@@ -70,10 +70,9 @@ STATIC mp_obj_t enumerate_make_new(const mp_obj_type_t *type, size_t n_args, siz
 MP_DEFINE_CONST_OBJ_TYPE(
     mp_type_enumerate,
     MP_QSTR_enumerate,
-    MP_TYPE_FLAG_NONE,
+    MP_TYPE_FLAG_ITER_IS_ITERNEXT,
     enumerate_make_new,
-    iternext, enumerate_iternext,
-    getiter, mp_identity_getiter
+    iter, enumerate_iternext
     );
 
 STATIC mp_obj_t enumerate_iternext(mp_obj_t self_in) {