# Copyright (c) 2017 Egor Tensin <Egor.Tensin@gmail.com>
# This file is part of the "VK scripts" project.
# For details, see https://github.com/egor-tensin/vk-scripts.
# Distributed under the MIT License.
from contextlib import contextmanager
import csv
import sys
class FileWriterCSV:
def __init__(self, fd=sys.stdout):
self._fd = fd
self._writer = csv.writer(fd, lineterminator='\n')
@staticmethod
def _convert_row_old_python(row):
if isinstance(row, list) or isinstance(row, tuple):
return row
return list(row)
def write_row(self, row):
if sys.version_info < (3, 5):
row = self._convert_row_old_python(row)
self._writer.writerow(row)
self._fd.flush()
class FileReaderCSV:
def __init__(self, fd=sys.stdin):
self._reader = csv.reader(fd)
def __iter__(self):
return iter(self._reader)
@contextmanager
def _open_file(path=None, default=None, **kwargs):
if path is None:
yield default
else:
with open(path, **kwargs) as fd:
yield fd
_DEFAULT_ENCODING = 'utf-8'
def open_output_text_file(path=None, mode='w'):
return _open_file(path, default=sys.stdout, mode=mode,
encoding=_DEFAULT_ENCODING)
def open_input_text_file(path=None):
return _open_file(path, default=sys.stdin, mode='r',
encoding=_DEFAULT_ENCODING)