searches for git repositories under the given directory and resets them to the latest master e.g., to reset all plugins to the latest: git_nuke.sh vendor/plugins or to reset the current repository and all git repos under it: git_nuke.sh .

git_nuke.sh

#!/bin/bash
if [ -z $1 ]
then
  echo "this thing will reset all nested git repos to HEAD/master"
  echo "specify a starting point"
  exit 1
fi
if [ -d $1 ]
then
  repos=`find $1 -name .git`
  for repo in $repos
  do
    repo=`dirname $repo`
    echo " * resetting $repo..."
    pushd $repo >/dev/null
    git checkout master
    git reset --hard origin/HEAD
    git pull
    popd >/dev/null
  done
else
  echo "Specify a starting directory"
  exit 1
fi