def _remove_unused_ignores()

in tools/upgrade/errors.py [0:0]

• 18 lines of code
• 8 McCabe index (conditional complexity)

def _remove_unused_ignores(line: str, errors: List[Dict[str, str]]) -> str:
    unused_ignore_codes = _get_unused_ignore_codes(errors)
    match = re.search(r"pyre-(ignore|fixme) *\[([0-9, ]+)\]", line)
    stripped_line = re.sub(r"# pyre-(ignore|fixme).*$", "", line).rstrip()
    if not match:
        return stripped_line

    # One or more codes are specified in the ignore comment.
    # Remove only the codes that are erroring as unused.
    ignore_codes_string = match.group(2)
    ignore_codes = [
        int(code.strip()) for code in ignore_codes_string.split(",") if code != ""
    ]
    remaining_ignore_codes = set(ignore_codes) - set(unused_ignore_codes)
    if len(remaining_ignore_codes) == 0 or len(unused_ignore_codes) == 0:
        return stripped_line
    else:
        return line.replace(
            ignore_codes_string,
            ", ".join([str(code) for code in remaining_ignore_codes]),
        )