Generated CMake config-file package for dedicated ROS interface package produces CMake error in find_package()

[asperry]

Context

I have a dedicated ament_cmake package for interfaces called my_robot_interfaces. I have another ament_cmake package called my_cpp_pkg that uses interfaces from my_robot_interfaces. The full packages can be found in this GitHub repository on the humble branch.

Problem

Compiling my_robot_interfaces succeeds without any stderr output. When I then attempt to compile my_cpp_pkg the build fails with the following CMake error triggered by the find_package(my_robot_interfaces REQUIRED) call:

CMake Error at /home/adam/ros2-sandbox-ws/install/my_robot_interfaces/share/my_robot_interfaces/cmake/ament_cmake_export_targets-extras.cmake:18 (message):
  Failed to find exported target names in
  '/home/adam/ros2-sandbox-ws/install/my_robot_interfaces/share/my_robot_interfaces/cmake/export_my_robot_interfaces__rosidl_generator_cExport.cmake'
Call Stack (most recent call first):
  /home/adam/ros2-sandbox-ws/install/my_robot_interfaces/share/my_robot_interfaces/cmake/my_robot_interfacesConfig.cmake:41 (include)
  CMakeLists.txt:17 (find_package)

Furthermore, upon inspection of the installed my_robot_interfaces package I find that the path to the interface headers has an extra my_robot_interfaces directory:

ros2-sandbox-ws/install/my_robot_interfaces/include/my_robot_interfaces/my_robot_interfaces/msg/
ros2-sandbox-ws/install/my_robot_interfaces/include/my_robot_interfaces/my_robot_interfaces/srv/

I believe this is not supposed to happen.

[asperry]

I'm very sorry that I failed to read the active issues before creating this issue. I had intended to do so, but in my focus on producing a complete report I apparently forgot. This issue is already treated by issue #13.