Rewrite git author

fix.sh

#!/bin/bash
set -euo pipefail
IFS=$'\n\t'

VERSION=$(git --version | cut -b13- | sed -n 's/.*[0-9]*\.\([0-9]*\)\.[0-9]*.*/\1/p')
if [ "$VERSION" -lt 15 ]; then
    echo "git version 2.15.0 or higher required"
    echo "please upgrade your git: brew upgrade git"
    exit 1
fi


##############################################################################
# CONFIG
##############################################################################
MASTER="master"
OLDMAIL="[email protected]"



################################################################################
## Here be dragons. Seriously, this is dark magic.
if [ "$1" = "" ]; then
    echo "usage: fix.sh PATH"
    echo ""
fi

branch=$(git -C $1 rev-parse --abbrev-ref HEAD)
git -C $1 filter-branch -f \
    --setup \
"
oldmail=\"$OLDMAIL\"
newname=\"$(git -C $1 config user.name)\"
newmail=\"$(git -C $1 config user.email)\"
branch=$(git -C $1 rev-parse --abbrev-ref HEAD)
" \
    --env-filter \
'
if [ "$GIT_COMMITTER_EMAIL" = "$oldmail" ]; then
    export GIT_COMMITTER_NAME="$newname"
    export GIT_COMMITTER_EMAIL="$newmail"
fi
if [ "$GIT_AUTHOR_EMAIL" = "$oldmail" ]; then
    export GIT_AUTHOR_NAME="$newname"
    export GIT_AUTHOR_EMAIL="$newmail"
fi
' --tag-name-filter cat -- $MASTER..$branch