Reverse time with this script!

Git Reverse

#!/bin/bash

function main () {
    local original_hash=$(get_current_commit_hash)

    go_to_project_root                           || exit 1
    create_new_branch                            || exit 1
    commit_with_copied_metadata ${original_hash} || exit 1

    for commit_hash in $(list_commit_hashes ${original_hash} | delete_last_line)
    do
        git diff ${commit_hash} ${commit_hash}~1 | patch --strip=1 --force || exit 1
        git add --all .                                                    || exit 1
        commit_with_copied_metadata ${commit_hash}~1                       || exit 1
    done
}

function go_to_project_root () {
    cd $(git rev-parse --show-toplevel)
}

function get_current_commit_hash () {
    git log -1 --pretty='%H' HEAD
}

function list_commit_hashes () {
    local start_commit=$1

    git log --pretty='%H' ${start_commit}
}

function delete_last_line () {
    sed -e '$d'
}

function create_new_branch () {
    git checkout --orphan nodnol
}

function commit_with_copied_metadata () {
    local source_commit=${1}

    git commit --reuse-message=${source_commit}                        \
        --author="$(git log -1 --pretty='%an <%ae>' ${source_commit})" \
        --date="$(git log -1 --pretty='%cd' ${source_commit})"
}

main

This reverses the order of the commits that are reachable from where you are when you run this command onto a new branch called nodnol.

This currently works against a repo which has a single line of commits. This is untested for merges.

This does not take special action to preserve any unstaged files. They will be committed along with the rest of the working directory into the first commit of the new branch.