py: Fix "TypeError: 'iterator' object is not iterable", doh.

py/objarray.c

@@ -219,6 +219,7 @@ STATIC mp_obj_t array_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t array_it_type = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = array_it_iternext,
 };
 

py/objdict.c

@@ -107,6 +107,7 @@ mp_obj_t dict_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t mp_type_dict_it = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = dict_it_iternext,
 };
 
@@ -336,6 +337,7 @@ STATIC mp_obj_t dict_view_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t dict_view_it_type = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = dict_view_it_iternext,
 };
 

py/objgetitemiter.c

@@ -38,6 +38,7 @@ STATIC mp_obj_t it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t it_type = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = it_iternext
 };
 

py/objlist.c

@@ -408,6 +408,7 @@ mp_obj_t list_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t mp_type_list_it = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = list_it_iternext,
 };
 

py/objrange.c

@@ -63,6 +63,7 @@ STATIC mp_obj_t range_it_iternext(mp_obj_t o_in) {
 STATIC const mp_obj_type_t range_it_type = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = range_it_iternext,
 };
 

py/objset.c

@@ -72,6 +72,7 @@ STATIC mp_obj_t set_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_
 const mp_obj_type_t mp_type_set_it = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = set_it_iternext,
 };
 

py/objstr.c

@@ -885,6 +885,7 @@ STATIC mp_obj_t str_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t mp_type_str_it = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = str_it_iternext,
 };
 
@@ -903,6 +904,7 @@ STATIC mp_obj_t bytes_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t mp_type_bytes_it = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = bytes_it_iternext,
 };
 

py/objtuple.c

@@ -251,6 +251,7 @@ STATIC mp_obj_t tuple_it_iternext(mp_obj_t self_in) {
 STATIC const mp_obj_type_t mp_type_tuple_it = {
     { &mp_type_type },
     .name = MP_QSTR_iterator,
+    .getiter = mp_identity,
     .iternext = tuple_it_iternext,
 };
 

tests/basics/iter-of-iter.py

@@ -0,0 +1,8 @@
+i = iter(iter((1, 2, 3)))
+print(list(i))
+i = iter(iter([1, 2, 3]))
+print(list(i))
+i = iter(iter({1:2, 3:4, 5:6}))
+print(list(i))
+i = iter(iter({1, 2, 3}))
+print(list(i))