Creating sparse checkout in a new linked git worktree

Hi All,

I am trying to get a sparse checkout in a linked worktree but cannot get
it working. I have tried the following

* git worktree add /some/new/path/new-branch --no-checkout
* git config core.sparseCheckout true
* <add the directory I would like to checkout out to
$GIT_DIR/info/sparse-checkout>
* cd  /some/new/path/new-branch
* git read-tree -mu sparse-checkout

But I still end up with a fully populated worktree.

Is there something I am missing or doing wrong?

thank you for any response.

jessie