[CMake] Fixed a problem when the Catch library folder was not placed under the root of project.

[COx2]

I found that the current description in CatchConfig.cmake does not resolve the path that references the Catch library when the project file structure is configured like below.

ProjectRoot
├── CMakeLists.txt
├── Examples
│        └── (example) 
└── External ......... Directory in which to place git submodules
          ├── link
          └── (other submodule)....... in my case, JUCE

For example, the CMakeLists.txt in project root has described to include the link library.

cmake_minimum_required(VERSION 3.15)

....

project(MyProject VERSION 0.0.1)

# Add Ableton Link library to this project
add_subdirectory(External/link)

# Add library from other submodule
add_subdirectory(External/(other submodule))

When you run Generate with CMake in the above example, you will get the following error message from CMake.

CMake Error in External/link/src/CMakeLists.txt:
  Imported target "Catch::Catch" includes non-existent path

    "(my_project_root)/third_party/catch"

  in its INTERFACE_INCLUDE_DIRECTORIES.  Possible reasons include:

  * The path was deleted, renamed, or moved to another location.

  * An install or uninstall procedure did not complete successfully.

  * The installation package was faulty and references files it does not
  provide.

The reason this happens is that the current CatchConfig.cmake specifies that there is the third_party/catch folder in the same directory of CMakeLists.txt, as shown below.

set_property(TARGET Catch::Catch APPEND PROPERTY
  INTERFACE_INCLUDE_DIRECTORIES
  ${CMAKE_SOURCE_DIR}/third_party/catch
)

The content of the proposal was based on the description in AsioStandaloneConfig.cmake.

Reference from AsioStandaloneConfig.cmake

set_property(TARGET AsioStandalone::AsioStandalone APPEND PROPERTY
  INTERFACE_INCLUDE_DIRECTORIES
  ${CMAKE_CURRENT_LIST_DIR}/../modules/asio-standalone/asio/include
)

Please, check it.

[fgo-ableton]

Thanks a lot! Even though it is only one line in the build system, could you please send us a CLA so I can merge this.

[COx2]

@fgo-ableton Understood. I have just submitted my signature to your company's CLA.

[fgo-ableton]

Thanks!

[COx2]

Thanks!