fix (#4419)

src/transformers/modeling_tf_utils.py

@@ -929,7 +929,9 @@ class TFPreTrainedModel(tf.keras.Model, TFModelUtilsMixin):
             else:
                 tokens_to_add = next_token
 
+            # add token and increase length by one
             input_ids = tf.concat([input_ids, tf.expand_dims(tokens_to_add, -1)], 1)
+            cur_len = cur_len + 1
 
             if eos_token_id is not None:
                 eos_in_sents = tokens_to_add == eos_token_id
@@ -955,8 +957,6 @@ class TFPreTrainedModel(tf.keras.Model, TFModelUtilsMixin):
                     [attention_mask, tf.ones((shape_list(attention_mask)[0], 1), dtype=tf.int32)], axis=-1
                 )
 
-            cur_len = cur_len + 1
-
         # if there are different sentences lengths in the batch, some batches have to be padded
         min_sent_length = tf.math.reduce_min(sent_lengths)
         max_sent_length = tf.math.reduce_max(sent_lengths)
@@ -970,7 +970,7 @@ class TFPreTrainedModel(tf.keras.Model, TFModelUtilsMixin):
                 tf.expand_dims(sent_lengths, -1), [batch_size, max_sent_length]
             )
             broad_casted_range = tf.transpose(
-                tf.broadcast_to(tf.expand_dims(tf.range(max_length), -1), [max_length, batch_size])
+                tf.broadcast_to(tf.expand_dims(tf.range(max_sent_length), -1), [max_sent_length, batch_size])
             )
 
             decoded = tf.where(broad_casted_range < broad_casted_sent_lengths, input_ids, padding)
@@ -1205,9 +1205,11 @@ class TFPreTrainedModel(tf.keras.Model, TFModelUtilsMixin):
             beam_tokens = tf.convert_to_tensor([x[1] for x in next_batch_beam], dtype=tf.int32)
             beam_idx = tf.convert_to_tensor([x[2] for x in next_batch_beam], dtype=tf.int32)
 
-            # re-order batch
+            # re-order batch and update current length
             input_ids = tf.stack([tf.identity(input_ids[x, :]) for x in beam_idx])
             input_ids = tf.concat([input_ids, tf.expand_dims(beam_tokens, 1)], axis=-1)
+            cur_len = cur_len + 1
+
             # re-order internal states
             if past is not None:
                 past = self._reorder_cache(past, beam_idx)
@@ -1218,9 +1220,6 @@ class TFPreTrainedModel(tf.keras.Model, TFModelUtilsMixin):
                     [attention_mask, tf.ones((shape_list(attention_mask)[0], 1), dtype=tf.int32)], axis=-1
                 )
 
-            # update current length
-            cur_len = cur_len + 1
-
         # finalize all open beam hypotheses and end to generated hypotheses
         for batch_idx in range(batch_size):
             # Add all open beam hypothesis to generated_hyps

src/transformers/modeling_utils.py

@@ -1236,13 +1236,15 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
             else:
                 tokens_to_add = next_token
 
+            # add token and increase length by one
             input_ids = torch.cat([input_ids, tokens_to_add.unsqueeze(-1)], dim=-1)
+            cur_len = cur_len + 1
 
             if eos_token_id is not None:
                 eos_in_sents = tokens_to_add == eos_token_id
                 # if sentence is unfinished and the token to add is eos, sent_lengths is filled with current length
                 is_sents_unfinished_and_token_to_add_is_eos = unfinished_sents.mul(eos_in_sents.long()).bool()
-                sent_lengths.masked_fill_(is_sents_unfinished_and_token_to_add_is_eos, cur_len + 1)
+                sent_lengths.masked_fill_(is_sents_unfinished_and_token_to_add_is_eos, cur_len)
                 # unfinished_sents is set to zero if eos in sentence
                 unfinished_sents.mul_((~eos_in_sents).long())
 
@@ -1256,8 +1258,6 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
                     [attention_mask, attention_mask.new_ones((attention_mask.shape[0], 1))], dim=-1
                 )
 
-            cur_len = cur_len + 1
-
         # if there are different sentences lengths in the batch, some batches have to be padded
         if sent_lengths.min().item() != sent_lengths.max().item():
             assert pad_token_id is not None, "`Pad_token_id` has to be defined if batches have different lengths"
@@ -1473,9 +1473,11 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
             beam_tokens = input_ids.new([x[1] for x in next_batch_beam])
             beam_idx = input_ids.new([x[2] for x in next_batch_beam])
 
-            # re-order batch
+            # re-order batch and update current length
             input_ids = input_ids[beam_idx, :]
             input_ids = torch.cat([input_ids, beam_tokens.unsqueeze(1)], dim=-1)
+            cur_len = cur_len + 1
+
             # re-order internal states
             if past is not None:
                 past = self._reorder_cache(past, beam_idx)
@@ -1486,9 +1488,6 @@ class PreTrainedModel(nn.Module, ModuleUtilsMixin):
                     [attention_mask, attention_mask.new_ones((attention_mask.shape[0], 1))], dim=-1
                 )
 
-            # update current length
-            cur_len = cur_len + 1
-
         # finalize all open beam hypotheses and end to generated hypotheses
         for batch_idx in range(batch_size):
             if done[batch_idx]: