Add tests for launch_utils of controller manager (#2147)

[robkwan]

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[christophfroehlich]

The tests you added are some sort of unit tests, checking if the returned objects are of expected type/size. But it does not check if the returned actions work as expected (let's call this integration test).

Can you please extract the new tests from this file (new tests are not testing ros2_control_node at all, and don't need launch_ros or launch_testing) in a launch_utils_unit_test file, and add distinct files for the integration tests of the three methods of the launch_utils? You could also extend the existing test_ros2_control_node_launch.py by adding more controllers, and spawn different combinations with the different methods at once.

Please also install pre-commit and fix the failing tests by running pre-commit run --all

[codecov]

Codecov Report

❌ Patch coverage is 88.23529% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.65%. Comparing base (a7e0b3a) to head (05e3d32).

Files with missing lines	Patch %	Lines
...ller_manager/test/test_ros2_control_node_launch.py	88.23%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2768      +/-   ##
==========================================
+ Coverage   89.62%   89.65%   +0.03%     
==========================================
  Files         152      152              
  Lines       17637    17670      +33     
  Branches     1448     1451       +3     
==========================================
+ Hits        15807    15842      +35     
+ Misses       1246     1241       -5     
- Partials      584      587       +3     

Flag	Coverage Δ
unittests	89.65% <88.23%> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...ller_manager/test/test_ros2_control_node_launch.py	94.66% <88.23%> (-5.34%)	⬇️

... and 2 files with indirect coverage changes

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[robkwan]

Thanks for the comment, @christophfroehlich! Let me try again then...