Enable TruncationStrategy override for pipelines

src/transformers/pipelines/base.py

@@ -24,7 +24,7 @@
 
 from ..file_utils import add_end_docstrings, is_tf_available, is_torch_available
 from ..modelcard import ModelCard
-from ..tokenization_utils import PreTrainedTokenizer
+from ..tokenization_utils import PreTrainedTokenizer, TruncationStrategy
 from ..utils import logging
 
 
@@ -577,7 +577,9 @@ def check_model_type(self, supported_models: Union[List[str], dict]):
                 f"The model '{self.model.__class__.__name__}' is not supported for {self.task}. Supported models are {supported_models}",
             )
 
-    def _parse_and_tokenize(self, inputs, padding=True, add_special_tokens=True, **kwargs):
+    def _parse_and_tokenize(
+        self, inputs, padding=True, add_special_tokens=True, truncation=TruncationStrategy.DO_NOT_TRUNCATE, **kwargs
+    ):
         """
         Parse arguments and tokenize
         """
@@ -587,6 +589,7 @@ def _parse_and_tokenize(self, inputs, padding=True, add_special_tokens=True, **k
             add_special_tokens=add_special_tokens,
             return_tensors=self.framework,
             padding=padding,
+            truncation=truncation,
         )
 
         return inputs

src/transformers/pipelines/conversational.py

@@ -2,6 +2,7 @@
 from typing import List, Optional, Union
 
 from ..file_utils import add_end_docstrings, is_tf_available, is_torch_available
+from ..tokenization_utils import TruncationStrategy
 from ..utils import logging
 from .base import PIPELINE_INIT_ARGS, Pipeline
 
@@ -317,12 +318,14 @@ def __call__(
             else:
                 return output
 
-    def _parse_and_tokenize(self, inputs, **kwargs):
+    def _parse_and_tokenize(
+        self, inputs, add_special_tokens=False, padding=False, truncation=TruncationStrategy.DO_NOT_TRUNCATE, **kwargs
+    ):
         """
         Parse arguments and tokenize, adding an EOS token at the end of the user input
         """
         # Parse arguments
-        inputs = self.tokenizer(inputs, add_special_tokens=False, padding=False).get("input_ids", [])
+        inputs = self.tokenizer(inputs, add_special_tokens=add_special_tokens, padding=padding).get("input_ids", [])
         for input in inputs:
             input.append(self.tokenizer.eos_token_id)
         return inputs

src/transformers/pipelines/text2text_generation.py

@@ -1,4 +1,5 @@
 from ..file_utils import add_end_docstrings, is_tf_available, is_torch_available
+from ..tokenization_utils import TruncationStrategy
 from ..utils import logging
 from .base import PIPELINE_INIT_ARGS, Pipeline
 
@@ -50,7 +51,13 @@ def check_inputs(self, input_length: int, min_length: int, max_length: int):
         return True
 
     def __call__(
-        self, *args, return_tensors=False, return_text=True, clean_up_tokenization_spaces=False, **generate_kwargs
+        self,
+        *args,
+        return_tensors=False,
+        return_text=True,
+        clean_up_tokenization_spaces=False,
+        truncation=TruncationStrategy.DO_NOT_TRUNCATE,
+        **generate_kwargs
     ):
         r"""
         Generate the output text(s) using text(s) given as inputs.
@@ -64,6 +71,10 @@ def __call__(
                 Whether or not to include the decoded texts in the outputs.
             clean_up_tokenization_spaces (:obj:`bool`, `optional`, defaults to :obj:`False`):
                 Whether or not to clean up the potential extra spaces in the text output.
+            truncation (:obj:`TruncationStrategy`, `optional`, defaults to :obj:`TruncationStrategy.DO_NOT_TRUNCATE`):
+                The truncation strategy for the tokenization within the pipeline.
+                :obj:`TruncationStrategy.DO_NOT_TRUNCATE` (default) will never truncate, but it is sometimes desirable
+                to truncate the input to fit the model's max_length instead of throwing an error down the line.
             generate_kwargs:
                 Additional keyword arguments to pass along to the generate method of the model (see the generate method
                 corresponding to your framework `here <./model.html#generative-models>`__).
@@ -96,7 +107,7 @@ def __call__(
             )
 
         with self.device_placement():
-            inputs = self._parse_and_tokenize(*args, padding=padding, **generate_kwargs)
+            inputs = self._parse_and_tokenize(*args, padding=padding, truncation=truncation)
 
             if self.framework == "pt":
                 inputs = self.ensure_tensor_on_device(**inputs)
@@ -108,9 +119,6 @@ def __call__(
             max_length = generate_kwargs.get("max_length", self.model.config.max_length)
             self.check_inputs(input_length, min_length, max_length)
 
-            # truncation should be used by _parse_and_tokenize
-            generate_kwargs.pop("truncation", None)
-
             generations = self.model.generate(
                 inputs["input_ids"],
                 attention_mask=inputs["attention_mask"],

src/transformers/pipelines/text_generation.py

@@ -50,25 +50,15 @@ def __init__(self, *args, **kwargs):
         self.check_model_type(self.ALLOWED_MODELS)
 
     # overriding _parse_and_tokenize to allow for unusual language-modeling tokenizer arguments
-
-    def _parse_and_tokenize(self, inputs, padding=True, add_special_tokens=True, **kwargs):
+    def _parse_and_tokenize(self, *args, **kwargs):
         """
         Parse arguments and tokenize
         """
         # Parse arguments
         if self.model.__class__.__name__ in ["TransfoXLLMHeadModel"]:
-            tokenizer_kwargs = {"add_space_before_punct_symbol": True}
-        else:
-            tokenizer_kwargs = {}
-        inputs = self.tokenizer(
-            inputs,
-            add_special_tokens=add_special_tokens,
-            return_tensors=self.framework,
-            padding=padding,
-            **tokenizer_kwargs,
-        )
-
-        return inputs
+            kwargs.update({"add_space_before_punct_symbol": True})
+
+        return super()._parse_and_tokenize(*args, **kwargs)
 
     def __call__(
         self,

src/transformers/pipelines/zero_shot_classification.py

@@ -3,6 +3,7 @@
 import numpy as np
 
 from ..file_utils import add_end_docstrings
+from ..tokenization_utils import TruncationStrategy
 from ..utils import logging
 from .base import PIPELINE_INIT_ARGS, ArgumentHandler, Pipeline
 
@@ -78,7 +79,14 @@ def entailment_id(self):
         return -1
 
     def _parse_and_tokenize(
-        self, sequences, candidate_labels, hypothesis_template, padding=True, add_special_tokens=True, **kwargs
+        self,
+        sequences,
+        candidate_labels,
+        hypothesis_template,
+        padding=True,
+        add_special_tokens=True,
+        truncation=TruncationStrategy.ONLY_FIRST,
+        **kwargs
     ):
         """
         Parse arguments and tokenize only_first so that hypothesis (label) is not truncated
@@ -89,7 +97,7 @@ def _parse_and_tokenize(
             add_special_tokens=add_special_tokens,
             return_tensors=self.framework,
             padding=padding,
-            truncation="only_first",
+            truncation=truncation,
         )
 
         return inputs

tests/test_pipelines_summarization.py

@@ -14,15 +14,72 @@
 
 import unittest
 
-from transformers import pipeline
+from transformers import AutoTokenizer, is_torch_available, pipeline
 from transformers.testing_utils import require_torch, slow, torch_device
+from transformers.tokenization_utils import TruncationStrategy
 
 from .test_pipelines_common import MonoInputPipelineCommonMixin
 
 
+if is_torch_available():
+    import torch
+
+    from transformers.models.bart import BartConfig, BartForConditionalGeneration
+
 DEFAULT_DEVICE_NUM = -1 if torch_device == "cpu" else 0
 
 
+class SimpleSummarizationPipelineTests(unittest.TestCase):
+    @require_torch
+    def test_input_too_long(self):
+        torch.manual_seed(0)
+        config = BartConfig(
+            vocab_size=257,
+            d_model=32,
+            encoder_layers=1,
+            decoder_layers=1,
+            encoder_ffn_dim=32,
+            decoder_ffn_dim=32,
+            # So any text > 4 should raise an exception
+            max_position_embeddings=4,
+            encoder_attention_heads=1,
+            decoder_attention_heads=1,
+            max_length=4,
+            min_length=1,
+        )
+        model = BartForConditionalGeneration(config)
+        # Bias output towards L
+        V, C = model.lm_head.weight.shape
+
+        bias = torch.zeros(V, requires_grad=True)
+        bias[76] = 10
+
+        model.lm_head.bias = torch.nn.Parameter(bias)
+
+        # # Generated with:
+        # import tempfile
+        # from tokenizers import Tokenizer, models
+        # from transformers import PreTrainedTokenizerFast
+        # model_max_length = 4
+        # vocab = [(chr(i), i) for i in range(256)]
+        # tokenizer = Tokenizer(models.Unigram(vocab))
+        # with tempfile.NamedTemporaryFile() as f:
+        #     tokenizer.save(f.name)
+        #     real_tokenizer = PreTrainedTokenizerFast(tokenizer_file=f.name, model_max_length=model_max_length)
+        # real_tokenizer._tokenizer.save("tokenizer.json")
+        # # + add missing config.json with albert as model_type
+        tokenizer = AutoTokenizer.from_pretrained("Narsil/small_summarization_test")
+        nlp = pipeline(task="summarization", model=model, tokenizer=tokenizer)
+
+        with self.assertLogs("transformers", level="WARNING"):
+            with self.assertRaises(IndexError):
+                _ = nlp("This is a test")
+
+        output = nlp("This is a test", truncation=TruncationStrategy.ONLY_FIRST)
+        # 2 is default BOS from Bart.
+        self.assertEqual(output, [{"summary_text": "\x02 L L L"}])
+
+
 class SummarizationPipelineTests(MonoInputPipelineCommonMixin, unittest.TestCase):
     pipeline_task = "summarization"
     pipeline_running_kwargs = {"num_beams": 2, "min_length": 2, "max_length": 5}