CMake errors when not using embedded json

[samwarring]

My project includes both inja and nlohmann/json as git submodules.

myproject
 - lib
   - json (git submodule)
   - inja (git submodule)
 - src
   - myproject.cpp
 - CMakeLists.txt

CMakeLists.txt pulls in the submodules with add_subdirectory(). By default INJA_USE_EMBEDDED_JSON is ON, and this results in the following CMake error:

 CMake Error at lib/inja/CMakeLists.txt:42 (add_library):
   add_library cannot create target "nlohmann_json" because another target
   with the same name already exists.  The existing target is an interface
   library created in source directory
   "/home/sam/GitHub/samwarring/nlf/lib/json".  See documentation for policy
   CMP0002 for more details.

This makes sense, since I've provided my own copy of nlohmann/json. However, if I set INJA_USE_EMBEDDED_JSON to OFF, I still get an error at generate-time:

 -- Configuring done
 CMake Error: install(EXPORT "injaTargets" ...) includes target "inja" which requires target "nlohmann_json" that is not in any export set.
 CMake Error in lib/inja/CMakeLists.txt:
   export called with target "inja" which requires target "nlohmann_json" that
   is not in any export set.
 
 
 -- Generating done
 CMake Generate step failed.  Build files cannot be regenerated correctly.

After disabling INJA_EXPORT and INJA_INSTALL, I'm still getting the above error. I think this is due to CMakeLists.txt:141 and CMakeLists:144, which have naked install and export commands that aren't wrapped with if (INJA_INSTALL) and if (INJA_EXPORT). I found wrapping those commands with if-statements fixes the problem. This might be the correct fix, but I could be misunderstanding.

[samwarring]

I should have checked the commit and issue history 🤦‍♂️ Looks like it's already reported in #237 and fixed on master. I was using the latest official release so I didn't see the change