Squash the last 'n' commits

squash

#!/bin/sh
# usage : squash 3 "new comment to replace the 3 last commits"
active_branch=$(git branch | head -n 1)
branch_name=${active_branch:2}
commits_to_squash=$1
new_commit_message=$2
git reset --soft HEAD~${commits_to_squash}
git commit -am "${new_commit_message}"
git push origin +${branch_name}