@@ -19,8 +19,9 @@ import logging
|
||||
import os
|
||||
import re
|
||||
from shutil import copyfile
|
||||
from typing import List, Optional
|
||||
|
||||
from .tokenization_utils import PreTrainedTokenizer
|
||||
from .tokenization_utils import BatchEncoding, PreTrainedTokenizer
|
||||
|
||||
|
||||
logger = logging.getLogger(__name__)
|
||||
@@ -96,6 +97,8 @@ class T5Tokenizer(PreTrainedTokenizer):
|
||||
max_model_input_sizes = PRETRAINED_POSITIONAL_EMBEDDINGS_SIZES
|
||||
model_input_names = ["attention_mask"]
|
||||
|
||||
prefix_tokens: List[int] = []
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
vocab_file,
|
||||
@@ -206,3 +209,127 @@ class T5Tokenizer(PreTrainedTokenizer):
|
||||
copyfile(self.vocab_file, out_vocab_file)
|
||||
|
||||
return (out_vocab_file,)
|
||||
|
||||
def build_inputs_with_special_tokens(
|
||||
self, token_ids_0: List[int], token_ids_1: Optional[List[int]] = None
|
||||
) -> List[int]:
|
||||
"""
|
||||
Build model inputs from a sequence or a pair of sequence for sequence classification tasks
|
||||
by concatenating and adding special tokens. The special tokens depend on calling source text or target text.
|
||||
A T5 sequence has the following format, where ``X`` represents the sequence:
|
||||
- ``input_ids`` (for encoder) ``X [eos]``
|
||||
- ``decoder_input_ids``: (for decoder) ``[pad] X [eos]``
|
||||
Pairs of sequences are not the expected use case, but they will be handled without a separator.
|
||||
|
||||
Args:
|
||||
token_ids_0 (:obj:`List[int]`):
|
||||
List of IDs to which the special tokens will be added
|
||||
token_ids_1 (:obj:`List[int]`, `optional`):
|
||||
Optional second list of IDs for sequence pairs.
|
||||
|
||||
Returns:
|
||||
:obj:`List[int]`: List of `input IDs <../glossary.html#input-ids>`__ with the appropriate special tokens.
|
||||
"""
|
||||
if token_ids_1 is None:
|
||||
return self.prefix_tokens + token_ids_0
|
||||
# We don't expect to process pairs, but leave the pair logic for API consistency
|
||||
return self.prefix_tokens + token_ids_0 + token_ids_1
|
||||
|
||||
def prepare_seq2seq_batch(
|
||||
self,
|
||||
src_texts: List[str],
|
||||
tgt_texts: Optional[List[str]] = None,
|
||||
max_length: Optional[int] = None,
|
||||
max_target_length: Optional[int] = None,
|
||||
padding: str = "longest",
|
||||
return_tensors: str = None,
|
||||
truncation: bool = True,
|
||||
**kwargs,
|
||||
) -> BatchEncoding:
|
||||
r"""
|
||||
Prepare a batch that can be passed directly to an instance of :class:`~transformers.T5Model`.
|
||||
Args:
|
||||
src_texts: (:obj:`List[str]`):
|
||||
List of documents to summarize or source language texts.
|
||||
tgt_texts: (:obj:`List[str]`, `optional`):
|
||||
List of summaries or target language texts.
|
||||
max_length (:obj:`int`, `optional`):
|
||||
Controls the maximum length for encoder inputs (documents to summarize or source language texts).
|
||||
If left unset or set to :obj:`None`, this will use the predefined model maximum length if a maximum
|
||||
length is required by one of the truncation/padding parameters. If the model has no specific maximum
|
||||
input length (like XLNet) truncation/padding to a maximum length will be deactivated.
|
||||
max_target_length (:obj:`int`, `optional`):
|
||||
Controls the maximum length of decoder inputs (target language texts or summaries).
|
||||
If left unset or set to :obj:`None`, this will use the max_length value.
|
||||
padding (:obj:`bool`, :obj:`str` or :class:`~transformers.tokenization_utils_base.PaddingStrategy`, `optional`, defaults to :obj:`False`):
|
||||
Activates and controls padding. Accepts the following values:
|
||||
* :obj:`True` or :obj:`'longest'`: Pad to the longest sequence in the batch (or no padding if only a
|
||||
single sequence if provided).
|
||||
* :obj:`'max_length'`: Pad to a maximum length specified with the argument :obj:`max_length` or to the
|
||||
maximum acceptable input length for the model if that argument is not provided.
|
||||
* :obj:`False` or :obj:`'do_not_pad'` (default): No padding (i.e., can output a batch with sequences of
|
||||
different lengths).
|
||||
return_tensors (:obj:`str` or :class:`~transformers.tokenization_utils_base.TensorType`, `optional`, defaults to "pt"):
|
||||
If set, will return tensors instead of list of python integers. Acceptable values are:
|
||||
* :obj:`'tf'`: Return TensorFlow :obj:`tf.constant` objects.
|
||||
* :obj:`'pt'`: Return PyTorch :obj:`torch.Tensor` objects.
|
||||
* :obj:`'np'`: Return Numpy :obj:`np.ndarray` objects.
|
||||
truncation (:obj:`bool`, :obj:`str` or :class:`~transformers.tokenization_utils_base.TruncationStrategy`, `optional`, defaults to :obj:`True`):
|
||||
Activates and controls truncation. Accepts the following values:
|
||||
* :obj:`True` or :obj:`'longest_first'`: Truncate to a maximum length specified with the argument
|
||||
:obj:`max_length` or to the maximum acceptable input length for the model if that argument is not
|
||||
provided. This will truncate token by token, removing a token from the longest sequence in the pair
|
||||
if a pair of sequences (or a batch of pairs) is provided.
|
||||
* :obj:`'only_first'`: Truncate to a maximum length specified with the argument :obj:`max_length` or to
|
||||
the maximum acceptable input length for the model if that argument is not provided. This will only
|
||||
truncate the first sequence of a pair if a pair of sequences (or a batch of pairs) is provided.
|
||||
* :obj:`'only_second'`: Truncate to a maximum length specified with the argument :obj:`max_length` or
|
||||
to the maximum acceptable input length for the model if that argument is not provided. This will only
|
||||
truncate the second sequence of a pair if a pair of sequences (or a batch of pairs) is provided.
|
||||
* :obj:`False` or :obj:`'do_not_truncate'` (default): No truncation (i.e., can output batch with
|
||||
sequence lengths greater than the model maximum admissible input size).
|
||||
**kwargs:
|
||||
Additional keyword arguments passed along to :obj:`self.__call__`.
|
||||
Returns:
|
||||
:class:`~transformers.BatchEncoding`: A :class:`~transformers.BatchEncoding` with the following fields:
|
||||
- **input_ids** -- List of token ids to be fed to the encoder.
|
||||
- **attention_mask** -- List of indices specifying which tokens should be attended to by the model.
|
||||
- **decoder_input_ids** -- List of token ids to be fed to the decoder.
|
||||
- **decoder_attention_mask** -- List of indices specifying which tokens should be attended to by the decoder.
|
||||
This does not include causal mask, which is built by the model.
|
||||
The full set of keys ``[input_ids, attention_mask, decoder_input_ids, decoder_attention_mask]``,
|
||||
will only be returned if tgt_texts is passed. Otherwise, input_ids, attention_mask will be the only keys.
|
||||
"""
|
||||
if max_length is None:
|
||||
max_length = self.max_len
|
||||
self.prefix_tokens = []
|
||||
model_inputs: BatchEncoding = self(
|
||||
src_texts,
|
||||
add_special_tokens=True,
|
||||
return_tensors=return_tensors,
|
||||
max_length=max_length,
|
||||
padding=padding,
|
||||
truncation=truncation,
|
||||
**kwargs,
|
||||
)
|
||||
if tgt_texts is None:
|
||||
return model_inputs
|
||||
# Process tgt_texts
|
||||
if max_target_length is None:
|
||||
max_target_length = max_length
|
||||
# set prefix_tokens for target text
|
||||
self.prefix_tokens = [self.pad_token_id]
|
||||
decoder_inputs: BatchEncoding = self(
|
||||
tgt_texts,
|
||||
add_special_tokens=True,
|
||||
return_tensors=return_tensors,
|
||||
padding=padding,
|
||||
max_length=max_target_length,
|
||||
truncation=truncation,
|
||||
**kwargs,
|
||||
)
|
||||
for k, v in decoder_inputs.items():
|
||||
model_inputs[f"decoder_{k}"] = v
|
||||
|
||||
self.prefix_tokens = []
|
||||
return model_inputs
|
||||
|
||||
@@ -17,6 +17,8 @@
|
||||
import os
|
||||
import unittest
|
||||
|
||||
from transformers import BatchEncoding
|
||||
from transformers.testing_utils import _torch_available
|
||||
from transformers.tokenization_t5 import T5Tokenizer
|
||||
from transformers.tokenization_xlnet import SPIECE_UNDERLINE
|
||||
|
||||
@@ -25,6 +27,8 @@ from .test_tokenization_common import TokenizerTesterMixin
|
||||
|
||||
SAMPLE_VOCAB = os.path.join(os.path.dirname(os.path.abspath(__file__)), "fixtures/test_sentencepiece.model")
|
||||
|
||||
FRAMEWORK = "pt" if _torch_available else "tf"
|
||||
|
||||
|
||||
class T5TokenizationTest(TokenizerTesterMixin, unittest.TestCase):
|
||||
|
||||
@@ -102,3 +106,77 @@ class T5TokenizationTest(TokenizerTesterMixin, unittest.TestCase):
|
||||
".",
|
||||
],
|
||||
)
|
||||
|
||||
def test_prepare_seq2seq_batch(self):
|
||||
tokenizer = T5Tokenizer.from_pretrained("t5-small")
|
||||
src_text = ["A long paragraph for summrization.", "Another paragraph for summrization."]
|
||||
tgt_text = [
|
||||
"Summary of the text.",
|
||||
"Another summary.",
|
||||
]
|
||||
expected_src_tokens = [71, 307, 8986, 21, 4505, 51, 52, 1707, 5]
|
||||
batch = tokenizer.prepare_seq2seq_batch(
|
||||
src_text, tgt_texts=tgt_text, max_length=len(expected_src_tokens), return_tensors=FRAMEWORK
|
||||
)
|
||||
self.assertIsInstance(batch, BatchEncoding)
|
||||
|
||||
self.assertEqual((2, 9), batch.input_ids.shape)
|
||||
self.assertEqual((2, 9), batch.attention_mask.shape)
|
||||
result = list(batch.input_ids.numpy()[0])
|
||||
self.assertListEqual(expected_src_tokens, result)
|
||||
# Test that special tokens are reset
|
||||
self.assertEqual(tokenizer.prefix_tokens, [])
|
||||
|
||||
def test_empty_target_text(self):
|
||||
tokenizer = T5Tokenizer.from_pretrained("t5-small")
|
||||
src_text = ["A long paragraph for summrization.", "Another paragraph for summrization."]
|
||||
batch = tokenizer.prepare_seq2seq_batch(src_text, return_tensors=FRAMEWORK)
|
||||
# check if input_ids are returned and no decoder_input_ids
|
||||
self.assertIn("input_ids", batch)
|
||||
self.assertIn("attention_mask", batch)
|
||||
self.assertNotIn("decoder_input_ids", batch)
|
||||
self.assertNotIn("decoder_attention_mask", batch)
|
||||
|
||||
def test_max_target_length(self):
|
||||
tokenizer = T5Tokenizer.from_pretrained("t5-small")
|
||||
src_text = ["A long paragraph for summrization.", "Another paragraph for summrization."]
|
||||
tgt_text = [
|
||||
"Summary of the text.",
|
||||
"Another summary.",
|
||||
]
|
||||
batch = tokenizer.prepare_seq2seq_batch(
|
||||
src_text, tgt_texts=tgt_text, max_target_length=32, padding="max_length", return_tensors=FRAMEWORK
|
||||
)
|
||||
self.assertEqual(32, batch["decoder_input_ids"].shape[1])
|
||||
self.assertEqual(32, batch["decoder_attention_mask"].shape[1])
|
||||
|
||||
# test None max_target_length
|
||||
batch = tokenizer.prepare_seq2seq_batch(
|
||||
src_text, tgt_texts=tgt_text, max_length=32, padding="max_length", return_tensors=FRAMEWORK
|
||||
)
|
||||
self.assertEqual(32, batch["decoder_input_ids"].shape[1])
|
||||
self.assertEqual(32, batch["decoder_attention_mask"].shape[1])
|
||||
|
||||
def test_outputs_not_longer_than_maxlen(self):
|
||||
tokenizer = T5Tokenizer.from_pretrained("t5-small")
|
||||
|
||||
batch = tokenizer.prepare_seq2seq_batch(
|
||||
["I am a small frog" * 1000, "I am a small frog"], return_tensors=FRAMEWORK
|
||||
)
|
||||
self.assertIsInstance(batch, BatchEncoding)
|
||||
self.assertEqual(batch.input_ids.shape, (2, 512))
|
||||
|
||||
def test_eos_in_input(self):
|
||||
tokenizer = T5Tokenizer.from_pretrained("t5-small")
|
||||
src_text = ["A long paragraph for summrization. </s>"]
|
||||
tgt_text = ["Summary of the text. </s>"]
|
||||
expected_src_tokens = [71, 307, 8986, 21, 4505, 51, 52, 1707, 5, 1]
|
||||
expected_tgt_tokens = [0, 20698, 13, 8, 1499, 5, 1]
|
||||
|
||||
batch = tokenizer.prepare_seq2seq_batch(src_text, tgt_texts=tgt_text, return_tensors=FRAMEWORK)
|
||||
|
||||
src_ids = list(batch.input_ids.numpy()[0])
|
||||
tgt_ids = list(batch.decoder_input_ids.numpy()[0])
|
||||
|
||||
self.assertEqual(expected_src_tokens, src_ids)
|
||||
self.assertEqual(expected_tgt_tokens, tgt_ids)
|
||||
|
||||
Reference in New Issue
Block a user