pathdiff

#!/bin/bash

from=$1
to=$2

diff -q -r "$from" "$to" | grep "Only in" | while IFS='' read -r line || [[ -n "$line" ]]; do
    path=$(echo "$line" | sed 's/^Only in \(.*\): .*$/\1/')
    file=$(echo "$line" | sed 's/^Only in .*: \(.*\)$/\1/')
    if [[ $path == "$from"* ]]; then
        echo "- $path/$file"
    else
        echo "+ $path/$file"
    fi
done