1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
|
# Copyright (c) DataLab Platform Developers, BSD 3-Clause license, see LICENSE file.
"""I/O utility functions."""
# pylint: disable=invalid-name # Allows short reference names like x, y...
from __future__ import annotations
import os
from itertools import islice
from sigima.io.enums import FileEncoding
def count_lines(filename: str | os.PathLike[str]) -> int:
"""Count the number of lines in a file.
Args:
filename: File name or path.
Returns:
The number of lines in the file.
Raises:
IOError: If the file cannot be read.
"""
for encoding in FileEncoding:
try:
with open(filename, "r", encoding=encoding) as file:
line_count = sum(1 for _ in file)
return line_count
except UnicodeDecodeError:
# Try next encoding.
pass
raise IOError(f"Cannot read file {filename}.")
def read_first_n_lines(filename: str | os.PathLike[str], n: int = 100000) -> str:
"""Read the first `n` lines of a file.
Args:
filename: File name or path.
n: Number of lines to read.
Returns:
The first `n` lines of the file.
Raises:
IOError: If the file cannot be read.
"""
for encoding in FileEncoding:
try:
with open(filename, "r", encoding=encoding) as file:
return "".join(islice(file, n))
except UnicodeDecodeError:
# Try next encoding.
pass
raise IOError(f"Cannot read file {filename}.")
|
