Aider-AI/aider · error · ValueError

Invalid version format, must be x.y.z: {new_version_str}

Error message

Invalid version format, must be x.y.z: {new_version_str}

What it means

scripts/versionbump.py enforces strict semver-triple input: args.new_version must fully match r'^\d+\.\d+\.\d+$' before anything is written. Anything else — '1.2', '1.2.3.4', 'v1.2.3', '1.2.3-rc1', leading/trailing spaces — raises ValueError with the offending string. The check runs after the pre-push guards (branch, clean tree, up-to-date main) unless --force was passed, so with --force this format error is the first thing you hit.

Source

Thrown at scripts/versionbump.py:101

    )
    parser.add_argument("--force", action="store_true", help="Skip pre-push checks")

    args = parser.parse_args()
    dry_run = args.dry_run
    force = args.force

    # Perform checks before proceeding unless --force is used
    if not force:
        check_branch()
        check_working_directory_clean()
        check_main_branch_up_to_date()
        check_ok_to_push()
    else:
        print("Skipping pre-push checks due to --force flag.")

    new_version_str = args.new_version
    if not re.match(r"^\d+\.\d+\.\d+$", new_version_str):
        raise ValueError(f"Invalid version format, must be x.y.z: {new_version_str}")

    new_version = version.parse(new_version_str)
    incremented_version = version.Version(
        f"{new_version.major}.{new_version.minor}.{new_version.micro + 1}"
    )

    from aider import __version__ as current_version

    if new_version <= version.parse(current_version):
        raise ValueError(
            f"New version {new_version} must be greater than the current version {current_version}"
        )

    with open("aider/__init__.py", "r") as f:
        content = f.read()
    updated_content = re.sub(r'__version__ = ".+?"', f'__version__ = "{new_version}"', content)

    print("Updating aider/__init__.py with new version:")

View on GitHub (pinned to 5dc9490bb3)

Solutions

1. Pass exactly three dot-separated integers, no 'v' prefix, no pre-release/build suffix: python scripts/versionbump.py 1.2.3.
2. Strip the prefix in your release wrapper if you copy tag names: ver=${tag#v}.
3. Keep pre-release handling out of this script — it only supports final x.y.z releases.

Example fix

# before
$ python scripts/versionbump.py v1.2.3  # ValueError: Invalid version format

# after
$ python scripts/versionbump.py 1.2.3

import re

def is_release_version(s: str) -> bool:
    return bool(re.fullmatch(r"\d+\.\d+\.\d+", s.strip()))

def is_release_version(s: str) -> bool:
    return isinstance(s, str) and re.fullmatch(r"\d+\.\d+\.\d+", s.strip()) is not None

When it happens

Trigger: python scripts/versionbump.py <arg> with a non x.y.z argument: 'v1.2.3' (leading v), '1.2.3-beta' (pre-release tag), '1.2' (short), or a typo like '1.2..3'. Regex is anchored (^...$) and numeric-only, so any deviation raises.

Common situations: Maintainers cutting releases who habitually type 'v1.2.3' matching git tag style, or copy pre-release identifiers from semver docs; the script's subsequent version.parse and the aider/__init__.py rewrite expect a bare dotted triple.

Related errors

• New version {new_version} must be greater than the current v
• Could not find version header in HISTORY.md
• Could not find start of release history
• Could not find version header: {version_header}
• Invalid line_endings value: {line_endings}. Must be one of:

AI-assisted analysis of Aider-AI/aider@5dc9490bb3 (2026-08-15). Data as JSON: /api/errors/7e621bd231730141. Report an issue: GitHub.