[CMake] Installing a helper application

[KC Jones]

I'm building an app on Mac, Linux, and Win.

My application requires that a helper application, built outside of my project, be installed along with it.  On Linux and Win, its sufficient to copy the helper app to the same directory as my app.  On Mac, it needs to be copied into the bundle in the same location as my runtime, in the Contents/Macos/ bundle directory.

I can't get the helper app to be packaged correctly on Mac.  I've tried two approaches that have come close but failed.

First I tried adding the helper as a target, then using install(TARGETS...):
----------------------------------------
ADD_EXECUTABLE(myapp MACOSX_BUNDLE [...])

SET(helperpath [...])
SET(IMPORTED_LOCATION ${helperpath})
ADD_EXECUTABLE(myhelper IMPORTED)

INSTALL(TARGETS myapp 
    BUNDLE DESTINATION .
    RUNTIME DESTINATION bin
)

INSTALL(TARGETS myhelper 
    BUNDLE DESTINATION .
    RUNTIME DESTINATION bin
)
----------------------------------------

This fails in cmake with a message: "install TARGETS given target "myhelper" which does not exist in this directory."

If  I alter the INSTALL with a fully qualified path to myhelper I get the same message, with the fully qualified myhelper path.

Next, I tried using INSTALL(PROGRAMS...) with something like:
----------------------------------------
ADD_EXECUTABLE(myapp MACOSX_BUNDLE [...])

SET(helperpath [...])

INSTALL(TARGETS myapp 
    BUNDLE DESTINATION .
    RUNTIME DESTINATION bin
)

INSTALL(PROGRAMS ${helperpath}/myhelper 
    DESTINATION .
)
----------------------------------------

But this form PROGRAMS does not support the kind-of qualifiers (BUNDLE, RUNTIME), so helperapp gets copied next to the bundle on Mac, not into it where it needs to be.

What am I doing wrong?

KC Jones
kc.jones at skype.net
SkypeId: bernalkc