fairseq/tests/test_sequence_scorer.py
Myle Ott ff68a9ef50 Add FairseqTask
A Task defines the data format, stores shared state (e.g., dictionaries) and provides helpers for building the model/criterion and calculating the loss.

Changes:
- Add TranslationTask and LanguageModelingTask. New tasks can be registered with @register_task decorator.
- Add EpochBatchIterator to encapsulate batching and saving/restoring dataloader position
- Remove LEFT_PAD_* constants and make them configurable per task
2018-06-15 13:05:22 -06:00

116 lines
3.9 KiB
Python

# Copyright (c) 2017-present, Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the license found in the LICENSE file in
# the root directory of this source tree. An additional grant of patent rights
# can be found in the PATENTS file in the same directory.
import argparse
import unittest
import torch
from fairseq.sequence_scorer import SequenceScorer
import tests.utils as test_utils
class TestSequenceScorer(unittest.TestCase):
def test_sequence_scorer(self):
# construct dummy dictionary
d = test_utils.dummy_dictionary(vocab_size=2)
self.assertEqual(d.pad(), 1)
self.assertEqual(d.eos(), 2)
self.assertEqual(d.unk(), 3)
eos = d.eos()
w1 = 4
w2 = 5
# construct dataloader
data = [
{
'source': torch.LongTensor([w1, w2, eos]),
'target': torch.LongTensor([w1, w2, w1, eos]),
},
{
'source': torch.LongTensor([w2, eos]),
'target': torch.LongTensor([w2, w1, eos]),
},
{
'source': torch.LongTensor([w2, eos]),
'target': torch.LongTensor([w2, eos]),
},
]
data_itr = test_utils.dummy_dataloader(data)
# specify expected output probabilities
args = argparse.Namespace()
unk = 0.
args.beam_probs = [
# step 0:
torch.FloatTensor([
# eos w1 w2
[0.0, unk, 0.6, 0.4], # sentence 1
[0.0, unk, 0.4, 0.6], # sentence 2
[0.0, unk, 0.7, 0.3], # sentence 3
]),
# step 1:
torch.FloatTensor([
# eos w1 w2
[0.0, unk, 0.2, 0.7], # sentence 1
[0.0, unk, 0.8, 0.2], # sentence 2
[0.7, unk, 0.1, 0.2], # sentence 3
]),
# step 2:
torch.FloatTensor([
# eos w1 w2
[0.10, unk, 0.50, 0.4], # sentence 1
[0.15, unk, 0.15, 0.7], # sentence 2
[0.00, unk, 0.00, 0.0], # sentence 3
]),
# step 3:
torch.FloatTensor([
# eos w1 w2
[0.9, unk, 0.05, 0.05], # sentence 1
[0.0, unk, 0.00, 0.0], # sentence 2
[0.0, unk, 0.00, 0.0], # sentence 3
]),
]
expected_scores = [
[0.6, 0.7, 0.5, 0.9], # sentence 1
[0.6, 0.8, 0.15], # sentence 2
[0.3, 0.7], # sentence 3
]
task = test_utils.TestTranslationTask.setup_task(args, d, d)
model = task.build_model(args)
scorer = SequenceScorer([model], task.target_dictionary)
for id, _src, _ref, hypos in scorer.score_batched_itr(data_itr):
self.assertHypoTokens(hypos[0], data[id]['target'])
self.assertHypoScore(hypos[0], expected_scores[id])
def assertHypoTokens(self, hypo, tokens):
self.assertTensorEqual(hypo['tokens'], torch.LongTensor(tokens))
def assertHypoScore(self, hypo, pos_probs, normalized=True, lenpen=1.):
pos_scores = torch.FloatTensor(pos_probs).log()
self.assertAlmostEqual(hypo['positional_scores'], pos_scores)
self.assertEqual(pos_scores.numel(), hypo['tokens'].numel())
score = pos_scores.sum()
if normalized:
score /= pos_scores.numel()**lenpen
self.assertLess(abs(score - hypo['score']), 1e-6)
def assertAlmostEqual(self, t1, t2):
self.assertEqual(t1.size(), t2.size(), "size mismatch")
self.assertLess((t1 - t2).abs().max(), 1e-4)
def assertTensorEqual(self, t1, t2):
self.assertEqual(t1.size(), t2.size(), "size mismatch")
self.assertEqual(t1.ne(t2).long().sum(), 0)
if __name__ == '__main__':
unittest.main()