def compare_rpm_versions()

in antlir/rpm/rpm_metadata.py [0:0]

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

def compare_rpm_versions(a: RpmMetadata, b: RpmMetadata) -> int:
    """
    Returns:
        1 if the version of a is newer than b
        0 if the versions match
        -1 if the version of a is older than b
    """

    # This is not a rule, but it makes sense that our libs don't want to
    # compare versions of different RPMs
    if a.name != b.name:
        raise ValueError("Cannot compare RPM versions when names do not match")

    # First compare the epoch, if set.  If the epoch's are not the same, then
    # the higher one wins no matter what the rest of the EVR is.
    if a.epoch != b.epoch:
        if a.epoch > b.epoch:
            return 1  # a > b
        else:
            return -1  # a < b

    # Epoch is the same, if version + release are the same we have a match
    if (a.version == b.version) and (a.release == b.release):
        return 0  # a == b

    # Compare version first, if version is equal then compare release
    compare_res = _compare_values(a.version, b.version)
    if compare_res != 0:  # a > b || a < b
        return compare_res
    else:
        return _compare_values(a.release, b.release)