How to test a DUB-based library during development?

[DanielG]

I want to create a library and eventually publish it via the DUB 
registry.

Is there a simple example that shows how to test the library 
during development, before publishing (ie, before being able to 
add it as a dependency to another project)?

I guess I'm just asking, what's the convention here? Do I create 
a separate project and then add my not-yet-published library via 
'dub add-local'? Put everything in a unittest in the library 
itself? etc etc.