Adding a -test sub-recipe

[Apologies if this appears twice - unsure if my first send worked]

I have a recipe which builds its libs/apps fine, and is installed into my rootfs; now I'm trying to add an additional 'test' subsection to the recipe in order to build and install some test apps.

I've added a do_compile_append-test() and do_install_append-test() for the additional test components, and the recipe builds these ok. But I'm struggling to get these added to the rootfs image.

I've listed the additional files in a FILES_${PN}-test= , and added a
PACKAGES += "FILES_${PN}-test" , and added IMAGE_INSTALL +=
"myrecipe-test" to the image recipe. However the do_rootfs() fails with

"Unable to locate package myrecipe-test"

I added

  RPROVIDES_${PN} += "myrecipe-test"

which 'resolves' the error, but the additional files aren't appearing in the rootfs.

What am I missing or getting wrong.?

The components are being put into the rootfs if I do the additions without the '-test' suffix (i.e. just adding them to the base recipe), but I'd like to have it as a separately-selectable option in the image recipe(s).