cornsnake.util_string

 1"""
 2Functions for working with strings: filtering by regex, checking if is mostly empty, replacing whilst maintaining casing.
 3
 4[Documentation](http://docs.mrseanryan.cornsnake.s3-website-eu-west-1.amazonaws.com/cornsnake/util_string.html)
 5"""
 6
 7import re
 8
 9
10def filter_string_via_regex(text: str, regex: str, replacement_char: str) -> str:
11    """
12    Filter the given string, to only characters that match the given regex.
13      - characters that do not match are replaced with 'replacement_char'
14
15    Example: filter_string_via_regex("this is a test 123 !@#", "_") -> "this_is_a_test_123____"
16    """
17
18    def _is_ok(c: str) -> bool:
19        return True if re.match(regex, c) else False
20
21    def _process_char(c: str) -> str:
22        return c if _is_ok(c) else replacement_char
23
24    return "".join([_process_char(c) for c in text])
25
26
27def is_empty(text: str) -> bool:
28    """
29    Function to check if a text string is empty or '-'.
30
31    Args:
32    text (str): The text string to check.
33
34    Returns:
35    bool: True if the text is empty (None or contains only whitespace or a hyphen), False otherwise.
36    """
37    if text is None:
38        return True
39    stripped = text.strip()
40    return stripped == "" or stripped == "-"
41
42
43def replace_keep_case(word__for_regex: str, replacement: str, text: str) -> str:
44    """
45    Replace ocurrences of 'word__for_regex' in 'text', with 'replacement', trying to maintain the same casing.
46
47    - supports lower, titla and upper casing
48    """
49
50    def func(match: re.Match[str]) -> str:
51        g = match.group()
52        if g.islower():
53            return replacement.lower()
54        if g.istitle():
55            return replacement.title()
56        if g.isupper():
57            return replacement.upper()
58        return replacement
59
60    return re.sub(word__for_regex, func, text, flags=re.I)
61
62
63def split_into_lines(text: str, max_length: int = 200) -> list[str]:
64    """
65    Split text into lines of maximum length at word boundaries.
66
67    Args:
68        text (str): Text to split
69        max_length (int): Maximum line length (default: 200)
70
71    Returns:
72        list: List of lines
73    """
74    if not text:
75        return []
76
77    result = []
78    current_line = ""
79
80    for word in text.split():
81        # Check if adding word would exceed max_length
82        if len(current_line) + len(word) + (1 if current_line else 0) <= max_length:
83            # Add word with a space if not the first word
84            current_line += " " + word if current_line else word
85        else:
86            # Line would be too long, start a new one
87            result.append(current_line)
88            current_line = word
89
90    # Add the last line if it has content
91    if current_line:
92        result.append(current_line)
93
94    return result