def test_with_file_where_we_need_to_read_more_than_chunk_size(self):
"""When we encounter character that may be part of a new line, we rewind further."""
with tempfile.NamedTemporaryFile(delete=False) as t:
t.write(b"abcd\nfg")
expected_result = (3, 4)
with io.open(t.name, mode="rb") as fp:
r = _get_what_to_read_next(
fp, previously_read_position=7, chunk_size=3
)
self.assertEqual(expected_result, r)
os.unlink(t.name)
def test_with_file_with_seven_bytes_of_alphanumeric(self):
"""Test with alpha-numeric contents of size 7 bytes with chunk_size of 3. Expect (4, 3)."""
with tempfile.NamedTemporaryFile(delete=False) as t:
t.write(b"abcdefg")
expected_result = (4, 3)
with io.open(t.name, mode="rb") as fp:
r = _get_what_to_read_next(
fp, previously_read_position=7, chunk_size=3
)
self.assertEqual(expected_result, r)
os.unlink(t.name)
def test_with_empty_file(self):
"""Expect (0, 0) when we pass in empty file."""
with tempfile.NamedTemporaryFile(delete=False) as t:
pass
expected_result = (0, 0)
with io.open(t.name, mode="rb") as fp:
r = _get_what_to_read_next(
fp, previously_read_position=0, chunk_size=3
)
self.assertEqual(expected_result, r)
os.unlink(t.name)
def test_with_file_with_single_new_line(self):
"""Test file with a single new line with variety of new_lines."""
for n in new_lines_bytes:
with tempfile.NamedTemporaryFile(delete=False) as t:
t.write(n)
expected_result = (0, len(n))
chunk_size = len(n) + 1 # chunk size must be greater than len(n)
with io.open(t.name, mode="rb") as fp:
r = _get_what_to_read_next(
fp, previously_read_position=len(n), chunk_size=chunk_size
)
self.assertEqual(r, expected_result)
os.unlink(t.name)