Yes:
git rev-parse --show-toplevel
If you want to replicate the Mercurial command more directly, you can create an alias:
git config --global alias.root 'rev-parse --show-toplevel'
and now git root
will function just as hg root
.
Note: In a submodule this will display the root directory of the submodule and not the parent repository. If you are using Git >=2.13 or above, there is a way that submodules can show the superproject’s root directory. If your git is older than that, see this other answer.