knit.orig

#!/bin/bash
#
# Originally written by Greg in 2019-01, for use in managing branches
# in his personal dotfiles repo (and named `meta/knit` in that tree.)

set -eu -o pipefail

die() {
    echo >&2 "${1}"
    exit 1
}

usage() {
    die "usage: ${0} HOST"
}

host="${1}"
case "${host}" in
    '')
        usage;;
    dark-matter|brown-dwarf)
        ;;
    *)
        die "unknown host: ${host}";;
esac

if ! git diff-index --quiet HEAD; then
    die "error: worktree not clean"
fi

branch_names=()
commit_ids=()
add_branch() {
    name="${1}"
    commit_id="$(
      git rev-parse --verify --quiet "${name}" \
      || git rev-parse --verify --quiet origin/"${name}"
      )"
    [ -n "${commit_id}" ] || return 1
    branch_names+=( "${name}" )
    commit_ids+=( "${commit_id}" )
}

add_branch master
add_branch datacomp
add_branch "${host}".only || :

git checkout "${commit_ids[0]}"
git merge "${commit_ids[@]:1}" \
    -m "Temp merge for ${host}: ${branch_names[*]:1}"