gen-version.sh

#!/usr/bin/env bash

# Copyright 2018-present RebirthDB
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may not use
# this file except in compliance with the License. You may obtain a copy of the
# License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software distributed
# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
# CONDITIONS OF ANY KIND, either express or implied. See the License for the
# specific language governing permissions and limitations under the License.
#
# This file incorporates work covered by the following copyright:
#
#     Copyright 2010-present, The Linux Foundation, portions copyright Google and
#     others and used with permission or subject to their respective license
#     agreements.
#
#     Licensed under the Apache License, Version 2.0 (the "License");
#     you may not use this file except in compliance with the License.
#     You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
#     Unless required by applicable law or agreed to in writing, software
#     distributed under the License is distributed on an "AS IS" BASIS,
#     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#     See the License for the specific language governing permissions and
#     limitations under the License.

set -euo pipefail

print_usage () {
    echo "Usage: $0 [-r|-h]"
    echo "  -r  Print number of revisions since v0.1 tag and exit"
    echo "  -h  Print help (this message)"
    echo "Otherwise generate a rebirthdb version number for this source tree"
}

main () {
    parse_opts "$@"

    root=$(dirname $0)/..
    export GIT_DIR="$root/.git"
    export GIT_WORK_TREE="$root"

    try_files "${VERSION_FILE:-}" "$root/VERSION.OVERRIDE" "./VERSION"

    if version=$(git_gen_version); then
        try_version "$version"
    fi

    if ! version=$(release_notes_version); then
        version=0.0-internal-unknown-fallback
    fi

    fallback_version=$version-fallback
    echo "$0: Warning: could not determine the version, using the default version '${fallback_version}'" >&2
    echo "$fallback_version"
}

lf='
'

try_files () {
    for file in "$@"; do
        if [[ -n "$file" && -f "$file" ]]; then
            try_version "$(cat $file)"
        fi
    done
}

try_version () {
    case "$1" in
        # If it is empty or contains newline or space, ignore it
        ""|*$lf*|*" "*) return;;
        # Otherwise strip a leading "v" and return it
        *) echo $1 | sed -e 's/^v//'; exit 0;;
    esac
}

parse_opts () {
    while getopts rsh opt; do
        case "$opt" in
            r) git rev-list v0.1..HEAD | wc -l; exit 0;;
            h) print_usage; exit 0;;
            ?) print_usage >&2; exit 1;;
        esac
    done
}

git_gen_version () {
    if version=$(git describe --tags --match "v[0-9]*" --abbrev=6 HEAD 2> /dev/null); then
        if git_is_dirty; then
            echo "$version-dirty"
        else
            echo "$version"
        fi
    else
        return 1
    fi
}

git_is_dirty () {
    test -n "$(git status --porcelain)"
}

release_notes_version () {
    grep Release "$root/NOTES.md" | egrep -o '[0-9]+(\.[0-9]+)+' | head -n 1
}

main "$@"