make package export files more modular

[nschloe]

Right now, linking information is stored in the project target file, e.g., TrilinosTargets.cmake where all packages of the project is gathered. This target file is then sourced from all package export config files as

# Import Trilinos targets                                                       
IF(NOT Trilinos_TARGETS_IMPORTED)                                               
  SET(Trilinos_TARGETS_IMPORTED 1)                                              
  INCLUDE("${CMAKE_CURRENT_LIST_DIR}/../Trilinos/TrilinosTargets.cmake")        
ENDIF()

(with the example being Trilinos here). This layout tightly ties together all export files of the project and makes it hard to use the export file of a (sub)package individually.

By

• exporting target files for each package individually,
• removing the project target file, and
• importing from each package only the dependent packages,

the currently functionality is exactly preserved, it will be possible to treat each package (with its dependencies) individually, and FIND_PACKAGE(<package_name>) will be allowed in applications.

[bartlettroscoe]

We will put this into the backlog for now.

[bartlettroscoe]

Sorry, did not mean to "close".

[nschloe]

I have a branch ready for this, but it doesn't seem to work quite yet with the STK/SEACAS integration. Not sure yet where the bug lies.

[bartlettroscoe]

Okay, so now that TriBITS requires CMake 2.8.11 and now that SEACAS has fixed their usage of SUBDIRS(), we can push #11?

[nschloe]

There are no tests for the export files yet; I suppose we should merge those in first. Otherwise LGTM.

[bartlettroscoe]

Is this not already resolved now that I have pushed you untangle_export_files branch?

[nschloe]

Indeed it is.