[cmake-developers] Should sucessive calls to find_package for one package succeed?

[Stephen Kelly]

Hi,

Should successive calls to find_package succeed in general?

Eg 

find_package(Grantlee COMPONENTS Templates)
find_package(Grantlee COMPONENTS TextDocument)

?

Currently if the target package uses Config files and 

install(TARGETS ... EXPORT)

the convention is to use

include(${CMAKE_CURRENT_LIST_DIR}/GrantleeTargets.cmake)

in the config file. The problem is that that Targets file uses an unguarded 

ADD_LIBRARY(grantlee_templates SHARED IMPORTED)

which cmake errors on:

  add_library cannot create imported target "grantlee_templates" because 
another target with the same name already exists.

The fix appears to be to wrap the call to add_library:

if (NOT TARGET grantlee_templates)
  ADD_LIBRARY(grantlee_templates SHARED IMPORTED)
endif()

I can fix this if it is a bug.

Thanks,

Steve.