py/runtime: Fix PEP479 behaviour throwing StopIteration into yield from.

Commit 3f6ffe059f64b3ebc44dc0bbc63452cb8850702b implemented PEP479 but did
not catch the case fixed in this commit.  Found by coverage analysis, that
the VM had uncovered code.

1 files changed, 2 insertions, 9 deletions

diff --git a/py/vm.c b/py/vm.c
index 6e5015fc4..7c702f386 100644
--- a/py/vm.c
+++ b/py/vm.c
@@ -1266,17 +1266,10 @@ yield:
                         DISPATCH();
                     } else {
                         assert(ret_kind == MP_VM_RETURN_EXCEPTION);
+                        assert(!EXC_MATCH(ret_value, MP_OBJ_FROM_PTR(&mp_type_StopIteration)));
                         // Pop exhausted gen
                         sp--;
-                        if (EXC_MATCH(ret_value, MP_OBJ_FROM_PTR(&mp_type_StopIteration))) {
-                            PUSH(mp_obj_exception_get_value(ret_value));
-                            // If we injected GeneratorExit downstream, then even
-                            // if it was swallowed, we re-raise GeneratorExit
-                            GENERATOR_EXIT_IF_NEEDED(t_exc);
-                            DISPATCH();
-                        } else {
-                            RAISE(ret_value);
-                        }
+                        RAISE(ret_value);
                     }
                 }