What dependencies to specify in CMakeLists.txt and which to specify in package.xml?
Even after having read this post regarding the difference between CMakeLists.xml and package.xml files (in the ROS context), I'm still not sure which dependencies should be specified in one or the other file.
I thought I needed to include (at least) in find_package (of the CMakeLists.xml) all the build dependencies (what about the other dependencies?) specified in the corresponding package.xml file, but this isn't the case, since I have a package where I'm specifying rospkg as a <build_depend> in package.xml, but if I also include rospkg in find_packages it gives me an error of the form
Could not find a package configuration file provided by "rospkg" with any of the following names:
rospkgConfig.cmake rospkg-config.cmake
On the other hand, a package like rospy also contains C++ code and I can include it in the find_package list.
The reason to have a package.xml and also a CMakeLists.txt is mainly due to, I guess, the need to support Python and C++ in ROS, but it's not very clear, again, which dependencies need to be specified in which files.
I checked the Github repository for rospkg and, indeed, it does not contain any C++ files (if I checked correctly), and thus it wouldn't make much sense to include rospkg in CMakeLists.xml...
