How to get the GraphObject at a given document point

How do you find the GraphObject at a given document point? I know you can find an object by name using findObject(), but am not seeing a method for finding one by position

Diagram.findObjectAt Diagram | GoJS API
Diagram.findPartAt Diagram | GoJS API

Note that Panel.findObject only finds a named GraphObject within the Panel. It does not search all Parts in a Diagram than might have a particular name. For that, you can just iterate over the Diagram.nodes or the data at Model.nodeDataArray to find the Node or node data object matching your search criteria.