hiera_include stopped working

This worked in version 3.7.4, and is broken in 3.7.5:
hiera_include('classes', '')
node foo {
}

But only as a catalog compile driven for nodes, I can't get it to happen for puppet apply.

It gets a failure of:
Error: Could not retrieve catalog from remote server: Error 400 on SERVER: Evaluation Error: Error while evaluating a Function Call, uninitialized constant Hiera::PuppetFunction at .../manifests/site.pp:48:1 on node puppetmaster

Where line 48 is where I have hiera_include('classes', '')