check target before linking

[Hunk86]

gmock isn't working with catkin
check if target is build that the linking doesn't fail

[v-lopez]

May I ask what error are you having? Do you have google-mock installed?

[Hunk86]

Of course

Using PYTHON_EXECUTABLE: /usr/bin/python2
Using Debian Python package layout
Using empy: /usr/bin/empy
Using CATKIN_ENABLE_TESTING: ON
Call enable_testing()
Using CATKIN_TEST_RESULTS_DIR: build/ddynamic_reconfigure/test_results
Found gtest: gtests will be built
Using Python nosetests: /usr/bin/nosetests-2.7
catkin 0.7.17
BUILD_SHARED_LIBS is on
[0m at ddynamic_reconfigure/CMakeLists.txt:54 (target_link_libraries):
  Cannot specify link libraries for target "ddynamic_reconfigure-test" which
  is not built by this project.
[0m Configuring incomplete, errors occurred!

I Installed google-mock by source. Which Version do you need ?

#
# Register the launch file with add_rostest() and compile all
# passed files into a GMock binary.
#
# .. note:: The function does nothing if GMock was not found.  The
#   target is only compiled when tests are built and linked against
#   the GMock libraries.
#
# :param target: target name of the GMock executable
# :type target: string
# :param launch_file: the relative path to the roslaunch file
# :type launch_file: string
# :param ARGN: the files to compile into a GMock executable
# :type ARGN: list of files
#
function(add_rostest_gmock target launch_file)
  _add_rostest_google_test("gmock" ${target} ${launch_file} ${ARGN})
endfunction()

-> I think in my case gmock isn't found, but this shouldn't give a linker error.

[v-lopez]

It should be installed via rosdep since it's listed on the package.xml as a dependency.

It shuold install a deb package called google-mock on ubuntu.

[Hunk86]

It is installed

Reading package lists... Done
Building dependency tree       
Reading state information... Done
google-mock is already the newest version (1.8.0-6).
google-mock set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 38 not upgraded.

[v-lopez]

You are on melodic I assume.

I just used a melodic docker from osrf and succesfully built the package and the tests.
With the same google-mock version.

I used

docker run -it osrf/ros:melodic-desktop-bionic bash
mkdir ws/src -p
cd ws/src
git clone https://github.com/pal-robotics/ddynamic_reconfigure
catkin_make
catkin_make tests

[Hunk86]

That is correct

The problem in my case is, that we build gtest by source and set the GTEST_ROOT= /opt/gtest.
With this catkin didn't find gmock, because catkin always expect gtest in /usr/include

[v-lopez]

I believe then it's better to make a PR for https://github.com/ros/catkin/blob/kinetic-devel/cmake/test/gtest.cmake

You can already disable the tests using CATKIN_ENABLE_TESTING.

[Hunk86]

In my opinion is to check if the target exist always a good proceed

But you are correct I also have to add a pullrequest for gtest.cmake that this will find a custom gmock installation