{"id":"4f19f33d3799d328","repo":"pypa/pip","slug":"dev-must-be-non-negative-integer-got-value","errorCode":null,"errorMessage":"dev must be non-negative integer, got {value}","messagePattern":"dev must be non-negative integer, got (.+?)","errorType":"validation","errorClass":"InvalidVersion","httpStatus":null,"severity":"error","filePath":"src/pip/_vendor/packaging/version.py","lineNumber":314,"sourceCode":"    raise InvalidVersion(msg)\n\n\ndef _validate_post(value: object, /) -> tuple[Literal[\"post\"], int] | None:\n    if value is None:\n        return value\n    if isinstance(value, int) and value >= 0:\n        return (\"post\", value)\n    msg = f\"post must be non-negative integer, got {value}\"\n    raise InvalidVersion(msg)\n\n\ndef _validate_dev(value: object, /) -> tuple[Literal[\"dev\"], int] | None:\n    if value is None:\n        return value\n    if isinstance(value, int) and value >= 0:\n        return (\"dev\", value)\n    msg = f\"dev must be non-negative integer, got {value}\"\n    raise InvalidVersion(msg)\n\n\ndef _validate_local(value: object, /) -> LocalType | None:\n    if value is None:\n        return value\n    if isinstance(value, str) and _LOCAL_PATTERN.fullmatch(value):\n        return _parse_local_version(value)\n    msg = f\"local must be a valid version string, got {value!r}\"\n    raise InvalidVersion(msg)\n\n\n# Backward compatibility for internals before 26.0. Do not use.\nclass _Version(NamedTuple):\n    epoch: int\n    release: tuple[int, ...]\n    dev: tuple[Literal[\"dev\"], int] | None\n    pre: tuple[Literal[\"a\", \"b\", \"rc\"], int] | None\n    post: tuple[Literal[\"post\"], int] | None","sourceCodeStart":296,"sourceCodeEnd":332,"githubUrl":"https://github.com/pypa/pip/blob/d7d0d0a39494e28ec1c407bd0680e4a4d1067791/src/pip/_vendor/packaging/version.py#L296-L332","documentation":"Raised by `_validate_dev(value)` when the `dev` argument to `Version.from_parts`/`__replace__` is not `None` and not a non-negative `int`. The dev-release number (`1.0.dev1`) is a single non-negative integer; strings, floats, lists, and negatives are rejected. The validator wraps it into `('dev', value)`.","triggerScenarios":"`Version.from_parts(release=(1,0), dev='0')`, `dev=-1`, `dev=0.0`, `dev=[1]`. Check is `isinstance(value, int) and value >= 0`.","commonSituations":"Dev number from a string config value; negative from computation; float from division.","solutions":["Pass a non-negative `int`: `dev=1`.","Coerce with `int(value)` and validate `>= 0` first.","Use `Version('1.0.dev1')` for string input.","Omit `dev` (`None`) if there is no dev-release segment."],"exampleFix":"// before\nVersion.from_parts(release=(1, 0), dev='1')  # str -> raises\n\n// after\nVersion.from_parts(release=(1, 0), dev=1)\n# or\nVersion('1.0.dev1')","handlingStrategy":"type-guard","validationCode":"def is_valid_dev(value: object) -> bool:\n    return value is None or (isinstance(value, int) and not isinstance(value, bool) and value >= 0)","typeGuard":"def is_non_negative_int_or_none(value: object) -> bool:\n    return value is None or (isinstance(value, int) and not isinstance(value, bool) and value >= 0)","tryCatchPattern":"from pip._vendor.packaging.version import Version, InvalidVersion\n\ntry:\n    v = Version.from_parts(release=release, dev=dev)\nexcept InvalidVersion as e:\n    if 'dev' in str(e):\n        dev = int(dev)\n        v = Version.from_parts(release=release, dev=dev)\n    raise","preventionTips":["Pass `dev` as a non-negative `int` or `None`.","Coerce strings with `int()` and validate `>= 0` before calling.","For string input, prefer `Version('1.0.dev1')`."],"tags":["python","packaging","version","pep440","validation","from-parts","dev-release"],"analyzedSha":"d7d0d0a39494e28ec1c407bd0680e4a4d1067791","analyzedAt":"2026-08-04T20:55:04.259Z","schemaVersion":2}