git diff for regular diff usage

diffg

#!/bin/sh
# git diff for regular diff usage

cmd=$(basename "$0")
[ "$1" = "--help" ] && {
    echo "$cmd [git diff options] fileA fileB"
    exit 0
}


a="$1"
b="$2"
shift 2
# Last two args are the files to compare; the rest are options.
opts=""
while [ "$1" ] ; do
    opts="$opts $a"
    a=$b
    b=$1
    shift
done

tmpdir=$cmd-$(date '+%Y%m%d%H%M%S')
mkdir "$tmpdir" && ln "$a" "$tmpdir"/a || exit 1
(cd "$tmpdir" && git init && git add a) > /dev/null
ln -f "$b" "$tmpdir"/a
(cd "$tmpdir" && git diff --color=always $opts | sed -n '/@@/,$p' | less -FRSX)
rm -rf "$tmpdir" || {
    echo "Failed to remove temp dir $tmpdir"
    exit 1
}