projektAI/venv/Lib/site-packages/pandas/tests/io/parser/test_compression.py
2021-06-06 22:13:05 +02:00

165 lines
5.0 KiB
Python

"""
Tests compressed data parsing functionality for all
of the parsers defined in parsers.py
"""
import os
from pathlib import Path
import zipfile
import pytest
from pandas import DataFrame
import pandas._testing as tm
@pytest.fixture(params=[True, False])
def buffer(request):
return request.param
@pytest.fixture
def parser_and_data(all_parsers, csv1):
parser = all_parsers
with open(csv1, "rb") as f:
data = f.read()
expected = parser.read_csv(csv1)
return parser, data, expected
@pytest.mark.parametrize("compression", ["zip", "infer", "zip2"])
def test_zip(parser_and_data, compression):
parser, data, expected = parser_and_data
with tm.ensure_clean("test_file.zip") as path:
with zipfile.ZipFile(path, mode="w") as tmp:
tmp.writestr("test_file", data)
if compression == "zip2":
with open(path, "rb") as f:
result = parser.read_csv(f, compression="zip")
else:
result = parser.read_csv(path, compression=compression)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("compression", ["zip", "infer"])
def test_zip_error_multiple_files(parser_and_data, compression):
parser, data, expected = parser_and_data
with tm.ensure_clean("combined_zip.zip") as path:
inner_file_names = ["test_file", "second_file"]
with zipfile.ZipFile(path, mode="w") as tmp:
for file_name in inner_file_names:
tmp.writestr(file_name, data)
with pytest.raises(ValueError, match="Multiple files"):
parser.read_csv(path, compression=compression)
def test_zip_error_no_files(parser_and_data):
parser, _, _ = parser_and_data
with tm.ensure_clean() as path:
with zipfile.ZipFile(path, mode="w"):
pass
with pytest.raises(ValueError, match="Zero files"):
parser.read_csv(path, compression="zip")
def test_zip_error_invalid_zip(parser_and_data):
parser, _, _ = parser_and_data
with tm.ensure_clean() as path:
with open(path, "rb") as f:
with pytest.raises(zipfile.BadZipfile, match="File is not a zip file"):
parser.read_csv(f, compression="zip")
@pytest.mark.parametrize("filename", [None, "test.{ext}"])
def test_compression(parser_and_data, compression_only, buffer, filename):
parser, data, expected = parser_and_data
compress_type = compression_only
ext = "gz" if compress_type == "gzip" else compress_type
filename = filename if filename is None else filename.format(ext=ext)
if filename and buffer:
pytest.skip("Cannot deduce compression from buffer of compressed data.")
with tm.ensure_clean(filename=filename) as path:
tm.write_to_compressed(compress_type, path, data)
compression = "infer" if filename else compress_type
if buffer:
with open(path, "rb") as f:
result = parser.read_csv(f, compression=compression)
else:
result = parser.read_csv(path, compression=compression)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("ext", [None, "gz", "bz2"])
def test_infer_compression(all_parsers, csv1, buffer, ext):
# see gh-9770
parser = all_parsers
kwargs = {"index_col": 0, "parse_dates": True}
expected = parser.read_csv(csv1, **kwargs)
kwargs["compression"] = "infer"
if buffer:
with open(csv1) as f:
result = parser.read_csv(f, **kwargs)
else:
ext = "." + ext if ext else ""
result = parser.read_csv(csv1 + ext, **kwargs)
tm.assert_frame_equal(result, expected)
def test_compression_utf_encoding(all_parsers, csv_dir_path, utf_value, encoding_fmt):
# see gh-18071, gh-24130
parser = all_parsers
encoding = encoding_fmt.format(utf_value)
path = os.path.join(csv_dir_path, f"utf{utf_value}_ex_small.zip")
result = parser.read_csv(path, encoding=encoding, compression="zip", sep="\t")
expected = DataFrame(
{
"Country": ["Venezuela", "Venezuela"],
"Twitter": ["Hugo Chávez Frías", "Henrique Capriles R."],
}
)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("invalid_compression", ["sfark", "bz3", "zipper"])
def test_invalid_compression(all_parsers, invalid_compression):
parser = all_parsers
compress_kwargs = {"compression": invalid_compression}
msg = f"Unrecognized compression type: {invalid_compression}"
with pytest.raises(ValueError, match=msg):
parser.read_csv("test_file.zip", **compress_kwargs)
def test_ignore_compression_extension(all_parsers):
parser = all_parsers
df = DataFrame({"a": [0, 1]})
with tm.ensure_clean("test.csv") as path_csv:
with tm.ensure_clean("test.csv.zip") as path_zip:
# make sure to create un-compressed file with zip extension
df.to_csv(path_csv, index=False)
Path(path_zip).write_text(Path(path_csv).read_text())
tm.assert_frame_equal(parser.read_csv(path_zip, compression=None), df)