Change authors in git-svn repository basing on git-svn's authorfile.

change-git-svn-authors.sh

#!/bin/sh
if [ -z "$1" ]
then
cat <<< HELP
(c) Marek 'saji' Augustynowicz
USAGE
    change-git-svn-authors.sh RELATIVE_PATH_TO_AUTHORS_FILE

Obtaining authors.txt for your repository
-----------------------------------------
    svn log -q SVN_REPO_URL | awk -F '|' '/^r/ {sub("^ ", "", $2); sub(" $", "", $2); print $2" = "$2" <"$2">"}' | sort -u > ../authors.txt
It produces file with lines:
    svn_username = svn_username <svn_username>
You have to manually change it into:
    svn_username = Name Surname <e.mail@example.com>
HELP
exit 1
fi

if ! [ -e "$1" ]
then
  echo "File `$1' does not exist."
  exit 2
fi

export AUTHORSFILE="$PWD/$1"

if ! [ -e "$AUTHORSFILE" ]
then
  echo "File `$AUTHORSFILE' does not exist."
  exit 3
fi

git-filter-branch --env-filter '
  LINE=$( grep -P "^$GIT_AUTHOR_NAME = " "$AUTHORSFILE" )"
  if [ -n "$LINE" ]
  then
    eval "$( sed -re 's/^([^ ]*) *= *(.*?) +<(.*)>$/SVN_USERNAME="\1" NAME="\2" EMAIL="\3"/' "$AUTHORSFILE" )"
    if [ -n "$NAME" ]
    then
      export GIT_AUTHOR_NAME="$NAME"
    fi
    if [ -n "$EMAIL" ]
    then
      export GIT_AUTHOR_EMAIL="$EMAIL"
    fi
  else
    echo "$GIT_AUTOR_NAME not found."
  fi
'