Bump Semantic Version Git Tag in Python

from re import match
from subprocess import run

SEMVER_PATTERN = r"^v(?P<major>0|[1-9]\d*)\.(?P<minor>0|[1-9]\d*)\.(?P<patch>0|[1-9]\d*)(?:-(?P<prerelease>[0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*))?(?:\+(?P<buildmetadata>[0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*))?$"


def get_latest_tag() -> str:
    result = run(["git", "describe", "--tags", "--abbrev=0"], capture_output=True, text=True)
    if result.returncode != 0:
        raise RuntimeError("No git tags found in this repository")
    return result.stdout.strip()


def bump_patch(tag: str) -> str:
    if not match(SEMVER_PATTERN, tag):
        raise ValueError(f"Invalid semver tag: {tag}")
    prefix = "v" if tag.startswith("v") else ""
    parts = tag.lstrip("v").split("-")[0].split(".")
    parts[2] = str(int(parts[2]) + 1)
    return f"{prefix}{'.'.join(parts)}"


if __name__ == "__main__":
    current = get_latest_tag()
    next_version = bump_patch(current)
    print(f"Current tag: {current}")
    print(f"Next release tag: {next_version}")