unstableGitUpdater: Add option to run the tag through a converter program

, branch ? null

, hardcodeZeroVersion ? false # Use a made-up version "0" instead of latest tag. Use when there is no previous release, or the project's tagging system is incompatible with what we expect from versions

, tagPrefix ? "" # strip this prefix from a tag name

, tagConverter ? null # A command to convert more complex tag formats. It receives the git tag via stdin and should convert it into x.y.z format to stdout

, shallowClone ? true

}:

    branch=""

    hardcode_zero_version=""

    tag_prefix=""

    tag_converter=""

    shallow_clone=""

    while (( $# > 0 )); do

          --tag-prefix=*)

            tag_prefix="''${flag#*=}"

            ;;

          --tag-converter=*)

            tag_converter="''${flag#*=}"

            ;;

          --shallow-clone)

            shallow_clone=1

            ;;

        if [[ -n "$tag_prefix" ]]; then

            last_tag="''${last_tag#$tag_prefix}"

        fi

        if [[ -n "$tag_converter" ]]; then

            last_tag="$(echo ''${last_tag#$tag_prefix} | ''${tag_converter})"

        fi

        if [[ ! "$last_tag" =~ ^[[:digit:]] ]]; then

            echo "Last tag '$last_tag' (after removing prefix '$tag_prefix') does not start with a digit" > /dev/stderr

            exit 1

  "--tag-prefix=${tagPrefix}"

] ++ lib.optionals (branch != null) [

  "--branch=${branch}"

] ++ lib.optionals (tagConverter != null) [

  "--tag-converter=${tagConverter}"

] ++ lib.optionals hardcodeZeroVersion [

  "--hardcode-zero-version"

] ++ lib.optionals shallowClone [