A far from perfect script helping you out to rewrite your author name and email in the git history of your repositories

deadname_rewriter.sh

# !/bin/bash

# Please don't trust me, I made this thing in a hurry and I'm not a Git expert.
# I copy pasted stuff from here and there, quickly read some git documentation and 
# made some trial and error locally.
# I've noticed that for some repositories it did not work, and also some commits went from "Verified" to "Unverified".
# I'm not sure why, I'm not sure how to fix it, the public keys match sooooo. That's an issue for future me.

# Create a mailmap in ~/.config/git/.mailmap (or anywhere else as long as you use it in the next command):
#
# Pattern is: New Name <new.email@bestdomain.tld> Old Name <oldemail>
# You can add as many aliases as you want, one per line
# I had multiple Git Author name and even email addresses. It was messy.
# You might have more or less lines that I do.
# 
# Alyx <github@alyx.pink> Old FirstName OldLastName <OldEmail>
# Alyx <github@alyx.pink> OldFirstName/Variant OldLastName <OldEmail>
# Alyx <github@alyx.pink> Alyx <oldEmail>
# Alyx <github@alyx.pink> Alyx Pink <OldEmail>
# Example: Alyx <github@alyx.pink> Foo Bar <foo.bar@example.com>


# Update all your commits following the matches in the mailmap files.
# If someone else made a commit, it should not be touched.
git filter-repo --force --mailmap ~/.config/git/.mailmap

# Re-sign every commits with my new identity
git filter-branch --force --commit-filter 'if [ "$GIT_COMMITTER_EMAIL" = "github@alyx.pink" ];
  then git commit-tree -S "$@";
  else git commit-tree "$@";
  fi' -- --all

# Update the remote for each repo
git remote add origin git@github.com:AlyxPink/$(basename $(pwd))

# Display log to check if everything is fine
git log --show-signature

# Push everything after a confirmation
read -p "Push all with force? (ctrl+c to cancel)" && git push --all --force