I installed git with `brew install git`

Now I want to use the **update-index** parameter, but that doesn't work because git-update-index is not installed.

How can I install this via Homebrew or another way for macOS?

**EDIT**

I am running macOS High Sierra 10.13.6 with git version 2.18.0 (both currently at the time of this writing).

```
$ type -a git
git is /usr/local/bin/git
git is /usr/bin/git

```

I'll check that tomorrow on work, because with my home-mac it works the correct way.