UT for src/guidellm/data/deserializers/file.py (#495)

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- [ ]

pytest tests/unit/data/deserializers/test_file.py

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- Resolves #

---

- [ ] "I certify that all code in this PR is my own, except as noted
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## Use of AI

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Author: sjmonson

tests/unit/data/deserializers/test_file.py

@@ -0,0 +1,368 @@
+import csv
+import io
+from pathlib import Path
+
+import pandas as pd
+import pyarrow as pa
+import pyarrow.parquet as pq
+import pytest
+from datasets import Dataset, DatasetDict
+from pyarrow import ipc
+
+from guidellm.data.deserializers.deserializer import DataNotSupportedError
+from guidellm.data.deserializers.file import (
+    ArrowFileDatasetDeserializer,
+    CSVFileDatasetDeserializer,
+    DBFileDatasetDeserializer,
+    HDF5FileDatasetDeserializer,
+    JSONFileDatasetDeserializer,
+    ParquetFileDatasetDeserializer,
+    TarFileDatasetDeserializer,
+    TextFileDatasetDeserializer,
+)
+
+
+def processor_factory():
+    return None
+
+
+###################
+# Tests text file deserializer
+###################
+
+
+@pytest.mark.sanity
+def test_text_file_deserializer_success(tmp_path):
+    # Arrange: create a temp text file
+    file_path = tmp_path / "sample.txt"
+    file_content = ["hello\n", "world\n"]
+    file_path.write_text("".join(file_content))
+
+    deserializer = TextFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=123,
+    )
+
+    # Assert
+    assert isinstance(dataset, Dataset)
+    assert dataset["text"] == file_content
+    assert len(dataset) == 2
+
+
+@pytest.mark.parametrize(
+    "invalid_data",
+    [
+        123,  # Not a path
+        None,  # Not a path
+        {"file": "abc.txt"},  # Wrong type
+    ],
+)
+@pytest.mark.sanity
+def test_text_file_deserializer_invalid_type(invalid_data):
+    deserializer = TextFileDatasetDeserializer()
+
+    with pytest.raises(DataNotSupportedError):
+        deserializer(
+            data=invalid_data,
+            processor_factory=processor_factory(),
+            random_seed=0,
+        )
+
+
+@pytest.mark.sanity
+def test_text_file_deserializer_file_not_exists(tmp_path):
+    deserializer = TextFileDatasetDeserializer()
+    non_existent_file = tmp_path / "missing.txt"
+
+    with pytest.raises(DataNotSupportedError):
+        deserializer(
+            data=non_existent_file,
+            processor_factory=processor_factory(),
+            random_seed=0,
+        )
+
+
+@pytest.mark.sanity
+def test_text_file_deserializer_not_a_file(tmp_path):
+    deserializer = TextFileDatasetDeserializer()
+    directory = tmp_path / "folder"
+    directory.mkdir()
+
+    with pytest.raises(DataNotSupportedError):
+        deserializer(
+            data=directory,
+            processor_factory=processor_factory(),
+            random_seed=0,
+        )
+
+
+@pytest.mark.sanity
+def test_text_file_deserializer_invalid_file_extension(tmp_path):
+    deserializer = TextFileDatasetDeserializer()
+
+    file_path = tmp_path / "data.ttl"
+    file_path.write_text("hello")
+
+    with pytest.raises(DataNotSupportedError):
+        deserializer(
+            data=file_path,
+            processor_factory=processor_factory(),
+            random_seed=0,
+        )
+
+
+###################
+# Tests parquet file deserializer
+###################
+
+
+def create_parquet_file(path: Path):
+    # Arrange: to create a minimal parquet file
+    table = pa.Table.from_pydict({"text": ["hello", "world"]})
+    pq.write_table(table, path)
+
+
+@pytest.mark.sanity
+def test_parquet_file_deserializer_success(tmp_path):
+    file_path = tmp_path / "sample.parquet"
+    create_parquet_file(file_path)
+
+    deserializer = ParquetFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=42,
+    )
+
+    # Assert
+    assert isinstance(dataset, DatasetDict)
+    assert dataset["train"].column_names == ["text"]
+    assert dataset["train"]["text"] == ["hello", "world"]
+    assert len(dataset["train"]["text"]) == 2
+
+
+@pytest.mark.sanity
+def test_parquet_file_deserializer_file_not_exists(tmp_path):
+    deserializer = ParquetFileDatasetDeserializer()
+    missing_file = tmp_path / "missing.parquet"
+
+    with pytest.raises(DataNotSupportedError):
+        deserializer(
+            data=missing_file,
+            processor_factory=processor_factory(),
+            random_seed=3,
+        )
+
+
+###################
+# Tests csv file deserializer
+###################
+
+
+def create_csv_file(path: Path):
+    """Helper to create a minimal csv file."""
+    output = io.StringIO()
+    writer = csv.writer(output)
+    writer.writerow(["text"])
+    writer.writerow(["hello world"])
+    with path.open("w") as f:
+        f.write(output.getvalue())
+
+
+@pytest.mark.sanity
+def test_csv_file_deserializer_success(tmp_path):
+    # Arrange: create a temp csv file
+    file_path = tmp_path / "sample.csv"
+    create_csv_file(file_path)
+
+    deserializer = CSVFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=43,
+    )
+
+    # Assert
+    assert isinstance(dataset, DatasetDict)
+    assert dataset["train"]["text"] == ["hello world"]
+    assert len(["train"]) == 1
+
+
+###################
+# Tests json file deserializer
+###################
+
+
+@pytest.mark.sanity
+def test_json_file_deserializer_success(tmp_path):
+    # Arrange: create a temp json file
+    file_path = tmp_path / "sample.json"
+    file_content = '{"text": "hello world"}\n'
+    file_path.write_text("".join(file_content))
+
+    deserializer = JSONFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=123,
+    )
+
+    # Assert
+    assert isinstance(dataset, DatasetDict)
+    assert dataset["train"]["text"] == ["hello world"]
+    assert len(dataset) == 1
+
+
+###################
+# Tests arrow file deserializer
+###################
+
+
+@pytest.mark.sanity
+def test_arrow_file_deserializer_success(monkeypatch, tmp_path):
+    # Arrange: create a temp arrow file
+    table = pa.Table.from_pydict({"text": ["hello", "world"]})
+    file_path = tmp_path / "sample.arrow"
+
+    with (
+        pa.OSFile(str(file_path), "wb") as sink,
+        ipc.RecordBatchFileWriter(sink, table.schema) as writer,
+    ):
+        writer.write_table(table)
+
+    deserializer = ArrowFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=42,
+    )
+
+    # assert
+    assert isinstance(dataset, DatasetDict)
+    assert "train" in dataset
+    assert isinstance(dataset["train"], Dataset)
+    assert dataset["train"].num_rows == 2
+
+
+###################
+# Tests HDF5 file deserializer
+###################
+
+
+@pytest.mark.skip(
+    reason="add pyproject extras group in the future \
+                to install hdf5 dependency such as pytables & h5py"
+)
+def test_hdf5_file_deserializer_success(tmp_path):
+    df_sample = pd.DataFrame({"text": ["hello", "world"]})
+    file_path = tmp_path / "sample.h5"
+    df_sample.to_hdf(str(file_path), key="data", mode="w", format="fixed")
+
+    deserializer = HDF5FileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=1,
+    )
+
+    # assert
+    assert isinstance(dataset, Dataset)
+    assert dataset.num_rows == 2
+    assert dataset["text"] == ["hello", "world"]
+
+
+##################
+# Tests DB file deserializer
+###################
+
+
+@pytest.mark.skip(reason="issue: #492")
+def test_db_file_deserializer_success(monkeypatch, tmp_path):
+    import sqlite3
+
+    def create_sqlite_db(path: Path):
+        conn = sqlite3.connect(path)
+        cur = conn.cursor()
+        cur.execute("CREATE TABLE samples (text TEXT)")
+        cur.execute("INSERT INTO samples (text) VALUES ('hello')")
+        cur.execute("INSERT INTO samples (text) VALUES ('world')")
+        conn.commit()
+        conn.close()
+
+    # Arrange: create a valid .db file
+    db_path = tmp_path / "sample.db"
+    create_sqlite_db(db_path)
+
+    # arrange: mock Dataset.from_sql return one dataset
+    mocked_ds = Dataset.from_dict({"text": ["hello", "world"]})
+
+    def mock_from_sql(sql, con, **kwargs):
+        assert sql == "SELECT * FROM samples"
+        assert con == (str(db_path))
+        return mocked_ds
+
+    monkeypatch.setattr("datasets.Dataset.from_sql", mock_from_sql)
+
+    deserializer = DBFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=db_path,
+        processor_factory=processor_factory(),
+        random_seed=1,
+    )
+
+    # Assert: result is of type Dataset
+    assert isinstance(dataset, Dataset)
+    assert dataset.num_rows == 2
+    assert dataset["text"] == ["hello", "world"]
+
+
+##################
+# Tests Tar file deserializer
+###################
+
+
+def create_simple_tar(tar_path: str):
+    import tarfile
+
+    # create tar 文件 in write mode
+    with tarfile.open(tar_path, "w") as tar:
+        # write content to be added to the tar file
+        content = b"hello world\nthis is a tar file\n"
+
+        # using BytesIO
+        data_stream = io.BytesIO(content)
+
+        # tarinfo: file description info
+        info = tarfile.TarInfo(name="sample.txt")
+        info.size = len(content)
+
+        # write file to tar archive
+        tar.addfile(info, data_stream)
+
+
+@pytest.mark.sanity
+def test_tar_file_deserializer_success(tmp_path):
+    file_path = tmp_path / "sample.tar"
+    create_simple_tar(file_path)
+
+    deserializer = TarFileDatasetDeserializer()
+
+    dataset = deserializer(
+        data=file_path,
+        processor_factory=processor_factory(),
+        random_seed=43,
+    )
+
+    assert isinstance(dataset, DatasetDict)
+    assert "train" in dataset
+    assert isinstance(dataset["train"], Dataset)
+    assert dataset["train"].num_rows == 1