Sync origin with upstream and clean everything locally.

git_sync_upstream.sh

#!/bin/bash

git fetch upstream

## Remove local branches
git remote prune upstream

## Clean all gone local branches
git fetch -p
for branch in `git branch -vv | grep ': gone]' | awk '{print $1}'`
do
  git branch -D $branch
done

## Remove origin branches that no longer exists on the upstream
BRANCH_1="upstream"
BRANCH_2="origin"

up=$(git branch -r | grep "$BRANCH_1")
BRANCHES=$(git branch -r | grep "$BRANCH_2" | sed -e "s/$BRANCH_2\///g" | grep -v "HEAD")

for i in $BRANCHES
do
  c=$(echo $up | grep -c "$i")
  if [ "$c" -lt 1 ]; then
    echo "PRUNING $i"
    git push -q origin :$i
  fi
done