diff --git a/onmt/translate/beam_search.py b/onmt/translate/beam_search.py
index 466cefd127..43865f1467 100644
--- a/onmt/translate/beam_search.py
+++ b/onmt/translate/beam_search.py
@@ -265,6 +265,12 @@ def update_finished(self):
 
         # reset the selection for the next step
         self.select_indices = self._batch_index.view(_B_new * self.beam_size)
+        # assert torch.equal(
+        #    self.src_len[self.select_indices],
+        #    self.src_len.view(_B_old, self.beam_size)[non_finished].view(
+        #        _B_new * self.beam_size
+        #    ),
+        # )
         self.src_len = self.src_len[self.select_indices]
         self.maybe_update_target_prefix(self.select_indices)