import unittest from swift.dataset import EncodePreprocessor, MessagesPreprocessor, PackingDataset, load_dataset from swift.model import get_processor from swift.template import get_template class TestDataPreprocess(unittest.TestCase): """Lightweight data preprocessing tests (no model forward/backward). These are fast tests suitable for CI. They cover: - SFT dataset encode (input_ids/labels) - Truncation/max_length - Data collator padding (attention_mask) - Multi-turn messages - Tool message - Packing dataset Why these tests are needed: - Swift's data preprocessing pipeline is complex (template -> encode -> collate -> pack). NPU training failures often stem from shape/mask/label mismatches before the model even sees the data, not from operator issues. - The original tests/general/test_dataset.py and test_template.py use top-level functions and remote 7B models, so they are never run by unittest discovery and are too heavy for CI. """ MODEL_PATH = 'Qwen/Qwen2-0.5B' @classmethod def setUpClass(cls): cls.processor = get_processor(cls.MODEL_PATH) cls.template = get_template(cls.processor) cls.template.mode = 'train' cls.template.init_processor(cls.processor) def _encode_dataset(self, dataset): encode_preprocessor = EncodePreprocessor(self.template) return encode_preprocessor(dataset, num_proc=1, load_from_cache_file=False, strict=False) def test_sft_dataset_encode(self): dataset, _ = load_dataset(['AI-ModelScope/alpaca-gpt4-data-zh#20'], num_proc=1, strict=False) self.assertGreater(len(dataset), 0) encoded_dataset = self._encode_dataset(dataset) first = encoded_dataset[0] self.assertIn('input_ids', first) self.assertIn('labels', first) self.assertEqual(len(first['input_ids']), len(first['labels'])) def test_truncation_max_length(self): self.template.max_length = 128 dataset, _ = load_dataset(['AI-ModelScope/alpaca-gpt4-data-zh#20'], num_proc=1, strict=False) encoded_dataset = self._encode_dataset(dataset) for row in encoded_dataset: self.assertLessEqual(len(row['input_ids']), self.template.max_length) self.template.max_length = None def test_data_collator_padding(self): dataset, _ = load_dataset(['AI-ModelScope/alpaca-gpt4-data-zh#20'], num_proc=1, strict=False) encoded_dataset = self._encode_dataset(dataset) batch = [encoded_dataset[i] for i in range(4)] collated = self.template.data_collator(batch) self.assertIn('input_ids', collated) self.assertIn('labels', collated) self.assertIn('attention_mask', collated) self.assertEqual(collated['input_ids'].shape[0], 4) def test_multi_turn_messages(self): multi_turn_row = { 'messages': [ { 'role': 'user', 'content': 'What is Python?' }, { 'role': 'assistant', 'content': 'Python is a programming language.' }, { 'role': 'user', 'content': 'What are its advantages?' }, { 'role': 'assistant', 'content': 'Python is easy to learn and use.' }, ] } encoded = self.template.encode(multi_turn_row, return_length=True) self.assertIn('input_ids', encoded) self.assertIn('labels', encoded) self.assertGreater(len(encoded['input_ids']), 0) self.assertEqual(len(encoded['input_ids']), len(encoded['labels'])) def test_tool_message(self): tool_row = { 'messages': [ { 'role': 'user', 'content': 'What is the weather in Beijing?' }, { 'role': 'assistant', 'content': '', 'tool_calls': [{ 'type': 'function', 'function': { 'name': 'get_weather', 'arguments': '{"city": "Beijing"}' } }] }, { 'role': 'tool', 'content': '{"temperature": 25, "condition": "sunny"}' }, { 'role': 'assistant', 'content': 'The weather in Beijing is sunny with a temperature of 25 degrees.' }, ] } encoded = self.template.encode(tool_row, return_length=True) self.assertIn('input_ids', encoded) self.assertIn('labels', encoded) self.assertGreater(len(encoded['input_ids']), 0) def test_packing_dataset(self): dataset, _ = load_dataset(['AI-ModelScope/alpaca-gpt4-data-zh#20'], num_proc=1, strict=False) encoded_dataset = self._encode_dataset(dataset) packing_dataset = PackingDataset( self.template, encoded_dataset, num_proc=1, strict=False, load_from_cache_file=False, packing_length=512, packing_num_proc=1, ) self.assertGreater(len(packing_dataset), 0) packed = packing_dataset[0] self.assertIsInstance(packed, list) self.assertGreater(len(packed), 0) self.assertIn('input_ids', packed[0]) self.assertIn('labels', packed[0]) class TestRejectedMessagesPreprocess(unittest.TestCase): """MessagesPreprocessor handling of rejected_messages (no model required).""" def test_empty_rejected_messages_does_not_crash(self): """A DPO row whose rejected_messages repair to empty must not crash. The recursive preprocess() call returns None when rejected_messages is empty (the same graceful-skip path used for the main messages list), so subscripting it with ['messages'] raised TypeError and aborted the whole dataset map. Downstream already treats rejected_messages is None as 'no rejected', so the row should fall back to None instead. """ row = { 'messages': [ { 'role': 'user', 'content': 'Q' }, { 'role': 'assistant', 'content': 'good' }, ], 'rejected_messages': [], } result = MessagesPreprocessor().preprocess(row) self.assertIsNotNone(result) self.assertIsNone(result['rejected_messages']) def test_valid_rejected_messages_preserved(self): row = { 'messages': [ { 'role': 'user', 'content': 'Q' }, { 'role': 'assistant', 'content': 'good' }, ], 'rejected_messages': [ { 'role': 'user', 'content': 'Q' }, { 'role': 'assistant', 'content': 'bad' }, ], } result = MessagesPreprocessor().preprocess(row) self.assertEqual(result['rejected_messages'][-1]['content'], 'bad') if __name__ == '__main__': unittest.main()