#!/bin/sh

export PATH=/usr/local/bin:/usr/bin:/bin

# cd to the root of the project directory (assume one dir up from GIT_DIR)
cd $GIT_DIR/..
unset GIT_DIR

# Set up some temporary files and a trap to delete them
oldlist=$(tempfile)
newlist=$(tempfile)
removelist=$(tempfile)
trap "rm -f $oldlist $newlist $removelist" 0 1 2 3 15

# Get list of files from the current index
git-ls-files | sort -r > $oldlist

# Checkout the index to the working directory
git-checkout-script -f

# Get list of files from the current (new) index
git-ls-files | sort -r > $newlist

# Use diff to determine which files to remove from the working copy
diff -u $oldlist $newlist |
  tail -n +4 |
  sed -n 's/^-//p' > $removelist

cat $removelist | xargs -rl rm -f
cat $removelist | xargs -rl dirname | xargs -rl rmdir -p --ignore-fail-on-non-empty