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ModuleNotFoundError python unit test

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  • #348 by @christophfroehlich — closed without merging

Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
testing

Research direction

Start with test/test_parameters.py and generate_parameter_module_example/minimal_publisher.py, then read the linked pull request #348 and related issues #192 and #141 to see what work is already underway. Reproduce the failure using the listed colcon build and colcon test commands. Done means the module imports successfully during the test run, not only when running pytest directly in the test folder.

Written by the indexing model from the issue text.

Description

Hello,

I am having errors when running colcon test for unit tests of python modules that use parameters generated by generate_parameter_library.

I have created a simple unit test that reproduces this error using your example_python on this branch: bug/python-example-unit-test. It simply imports the minimal_publisher module.

Here are the steps to reproduce the error:

  1. rosdep update
  2. rosdep install --rosdistro humble
  3. colcon build --cmake-args -DBUILD_TESTING=1 -DCMAKE_EXPORT_COMPILE_COMMANDS=On --event-handlers console_direct+ --merge-install
  4. colcon test --merge-install --packages-select generate_parameter_module_example --event-handlers console_cohesion+ log_command+ summary+ --return-code-on-test-failure

The result should give something like the following:

==================================== ERRORS ====================================
________________________ ERROR collecting test session _________________________
/usr/lib/python3/dist-packages/pluggy/hooks.py:286: in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
/usr/lib/python3/dist-packages/pluggy/manager.py:92: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/usr/lib/python3/dist-packages/pluggy/manager.py:83: in <lambda>
    self._inner_hookexec = lambda hook, methods, kwargs: hook.multicall(
/usr/lib/python3/dist-packages/_pytest/python.py:200: in pytest_collect_file
    module: Module = ihook.pytest_pycollect_makemodule(path=path, parent=parent)
/usr/lib/python3/dist-packages/pluggy/hooks.py:286: in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
/usr/lib/python3/dist-packages/pluggy/manager.py:92: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/usr/lib/python3/dist-packages/pluggy/manager.py:83: in <lambda>
    self._inner_hookexec = lambda hook, methods, kwargs: hook.multicall(
/opt/ros/humble/lib/python3.10/site-packages/launch_testing/pytest/hooks.py:193: in pytest_pycollect_makemodule
    entrypoint = find_launch_test_entrypoint(path)
/opt/ros/humble/lib/python3.10/site-packages/launch_testing/pytest/hooks.py:186: in find_launch_test_entrypoint
    module = path.pyimport()
/usr/lib/python3/dist-packages/py/_path/local.py:704: in pyimport
    __import__(modname)
/usr/lib/python3/dist-packages/_pytest/assertion/rewrite.py:170: in exec_module
    exec(co, module.__dict__)
test/test_parameters.py:3: in <module>
    import generate_parameter_module_example.minimal_publisher
generate_parameter_module_example/minimal_publisher.py:30: in <module>
    from generate_parameter_module_example.admittance_parameters import (
E   ModuleNotFoundError: No module named 'generate_parameter_module_example.admittance_parameters'
- generated xml file: /home/user/ws/build/generate_parameter_module_example/pytest.xml -
=========================== short test summary info ============================
ERROR  - ModuleNotFoundError: No module named 'generate_parameter_module_exam...
!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!
=============================== 1 error in 0.11s ===============================

Note: It seems to work if you run pytest directly inside the test/ folder.

@christophfroehlich I'm not sure who to tag, but I appreciate any help with this. Thanks!

(possible related issues: #192, #141)

Context:

  • Ros Distro: Humble
  • Ubuntu 22.04
Dominant language
Python
Stars
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Forks
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No merged PRs in 30d

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