test_cli.py misses launch_ros for rmw_cyclonedds_cpp

[brawner]

This affects multiple packages, I'm still looking into which test_cli failures are just due to this. So far

ros2node:
test_cli::test_list_node_count
test_cli::test_list_all_nodes_count
ros2service
test_cli::test_list_count

With ros2node it gets the following for listing nodes. Inspecting the output of ros2 node list -a, it reports:

/_hidden_complex_node
/_ros2cli_daemon_1
/complex_node

The test appears to be missing launch_ros

https://ci.ros2.org/view/nightly/job/nightly_win_extra_rmw_rel/673/testReport/ros2node.test/test_cli/test_cli/
https://ci.ros2.org/view/nightly/job/nightly_linux_extra_rmw_release/619/testReport/ros2node.test/test_cli/test_cli/

[rotu]

@brawner please clarify what you mean that it "misses" launch_ros. What is the issue?

[brawner]

During the above linked failures, the expected number of nodes doesn't match what it actually finds. When I was digging into this, the launch_ros node is running, but it's not found during this test

Traceback (most recent call last):
  File "/home/jenkins-agent/workspace/nightly_linux_extra_rmw_release/ws/install/launch_testing/lib/python3.6/site-packages/launch_testing/markers.py", line 48, in _wrapper
    return func(self, *args, **kwargs)
  File "/home/jenkins-agent/workspace/nightly_linux_extra_rmw_release/ws/src/ros2/ros2cli/ros2node/test/test_cli.py", line 153, in test_list_all_nodes_count
    assert int(output_lines[0]) == 4
AssertionError: assert 3 == 4
 +  where 3 = int('3')

It still is happening in recent tests, you can search the consoleText:
FAIL: test_list_all_nodes_count[rmw_cyclonedds_cpp] (test_cli.TestROS2NodeCLI)
https://ci.ros2.org/view/nightly/job/nightly_linux_extra_rmw_release/653/consoleText

[rotu]

Ah... Seems to be caused by ros2/launch_ros#128, which by eliminating default_launch_description.py got rid of extra implementation nodes.

[brawner]

This failure has been ongoing for awhile now and still occurs after that PR was merged, but I'm also not familiar enough with this everything involved to suggest what's causing the issue.

[rotu]

Ya. It looks like the nodes aren't being "missed" - they just don't exist anymore. And it seems to have been caused at least in part by that PR. So it's a naughty test, not a misbehavior of ros2 node list -a -c.

[brawner]

Now the behavior is more consistent among the different DDS implementations. Maybe the test just needs to be updated? It fails now with connext, fastrtps, cyclonedds

Some more examples
https://ci.ros2.org/view/nightly/job/nightly_linux_release/1486/testReport/ros2service.src.ros2.ros2cli.ros2service.test/test_cli/test_cli/
https://ci.ros2.org/view/nightly/job/nightly_win_extra_rmw_rel/703/testReport/ros2node.src.ros2.ros2cli.ros2node.test/test_cli/test_cli/

[clalancette]

This is an old issue, and I don't think that we are having this exact problem anymore in CI, so I'm going to close this. Feel free to reopen if you still think this is a problem.