Gitx has a great diff viewer, how do I make git automatically pipe git diff whatever into gitx?

I've tried to set git config diff.external to a shell script that looks like this:

git diff "$2" "$5" | gitx

However, that only opens all the individual files up into multiple gitx windows, and it really messes up the files names (changes them all to tmp files with crazy names).

Does anyone have a better solution?

git macos diff
Edit
Report