Fix ament_target_dependencies accepting non-packages

[sloretz]

This quotes a cmake variable to avoid some weird behavior that causes a check to always evaluate to false, even for non-packages.

If package_name has been found then if(NOT ${${package_name}_FOUND}) becomes if(NOT 1), and the condition is false as intended.

If package_name is not a package name then ${package_name}_FOUND isn't a variable, so ${${package_name}_FOUND} is an empty string. Since the string is unquoted it gets expanded into zero arguments, and the actual condition becomes if(NOT) which evaluates to false too.

Thanks to @aaronchongth for finding the cmake issue: https://gitlab.kitware.com/cmake/cmake/issues/19379

[ivanpauno]

and the actual condition becomes if(NOT) which evaluates to false too.

That's fun 🤣.

[sloretz]

CI (build all, test ament_cmake_target_dependencies)

• Linux
• Linux-aarch64
• macOS
• Windows

[sloretz]

CI for this and referenced PRs

• Building all
• Testing:
  • ament_cmake_target_dependencies
  • examples_rclcpp_minimal_composition
  • rclcpp_components
  • rttest rosidl_generator_c
  • rosidl_generator_py
  • rosidl_typesupport_connext_c
  • rosidl_typesupport_fastrtps_c
  • rviz_rendering_tests
• Linux
• Linux-aarch64
• macOS
• Windows

[sloretz]

CI again with feedback and linter fixes

• Linux
• Linux-aarch64
• macOS
• Windows

Edit: CI looks ok, just

cmake/rclcpp_components_register_node.cmake:33: Line ends in whitespace [whitespace/eol]

Which appears to be caused by ros2/rclcpp#784