Fix oneof encoding/decoding

1 files changed, 7 insertions, 1 deletions

diff --git a/upb/encode.c b/upb/encode.c
index f01ad0c..67678fe 100644
--- a/upb/encode.c
+++ b/upb/encode.c
@@ -360,7 +360,13 @@ bool upb_encode_message(upb_encstate* e, const char *msg,
       CHK(upb_encode_array(e, msg + f->offset, m, f));
     } else {
       if (upb_encode_hasscalarfield(msg, m, f)) {
-        CHK(upb_encode_scalarfield(e, msg + f->offset, m, f, !m->is_proto2));
+        if (f->oneof_index != UPB_NOT_IN_ONEOF) {
+          const upb_msglayout_oneofinit_v1 *o = &m->oneofs[f->oneof_index];
+          CHK(upb_encode_scalarfield(e, msg + o->data_offset,
+                                     m, f, !m->is_proto2));
+        } else {
+          CHK(upb_encode_scalarfield(e, msg + f->offset, m, f, !m->is_proto2));
+        }
       }
     }
   }