elevation_ws

Imported from OmarXFlex/elevation_ws (AGENTS.md). Install upstream with npx skills add OmarXFlex/elevation_ws. Copyright stays with the author.

Testing Guide for elevation_mapping_cupy

Running Tests Locally

Prerequisites

# Source ROS2
source /opt/ros/jazzy/setup.bash

# Build the package
colcon build --packages-select elevation_mapping_cupy

# Source the workspace
source install/setup.bash

Run All Tests via colcon

colcon test --packages-select elevation_mapping_cupy --event-handlers console_direct+

Run Unit Tests Only (pytest)

These are the primary regression tests for the axis-swap bug. They don't require ROS nodes to be running.

# Run all unit tests
cd elevation_mapping_cupy/elevation_mapping_cupy/tests/
PYTEST_DISABLE_PLUGIN_AUTOLOAD=1 pytest -v

# Run specific test file
PYTEST_DISABLE_PLUGIN_AUTOLOAD=1 pytest test_map_shifting.py -v

# Run specific test
PYTEST_DISABLE_PLUGIN_AUTOLOAD=1 pytest test_map_shifting.py::TestShiftMapXY::test_shift_x_only_affects_columns -v

Run Integration Tests Only (launch_testing)

These test the full TF → GridMap pipeline with actual ROS nodes.

# Stop daemon first to avoid DDS issues
ros2 daemon stop

# Run with DDS fixes
FASTDDS_BUILTIN_TRANSPORTS=UDPv4 python3 -m launch_testing.launch_test \
    src/elevation_mapping_cupy/elevation_mapping_cupy/test/test_tf_gridmap_integration.py

Test Summary

ROS2 Integration Testing: DDS Discovery Fixes

This document captures lessons learned from fixing DDS discovery issues in launch_testing integration tests.

Problem

DDS discovery between the test fixture process and launched nodes fails intermittently in launch_testing. Symptoms:

• Test fixture cannot subscribe to topics published by launched nodes
• wait_for_gridmap() times out even though node is publishing
• Tests pass locally sometimes but fail in CI

Root Causes & Fixes

1. ROS2 Daemon RMW Mismatch

Cause: The ROS2 daemon may be running with a different RMW implementation than the tests. This causes discovery timeouts.

Fix: Stop the daemon before tests run.

# In generate_test_description() or setUpClass()
import subprocess
subprocess.run(['ros2', 'daemon', 'stop'], capture_output=True)

Source: ros2/system_tests#460

2. FastDDS Shared Memory Transport Issues

Cause: FastDDS uses shared memory (SHM) by default for same-machine communication. This can fail in certain environments (Docker, VMs, some Linux configurations).

Fix: Force UDPv4 transport instead of shared memory.

# In Python
import os
os.environ['FASTDDS_BUILTIN_TRANSPORTS'] = 'UDPv4'

# In CMakeLists.txt
add_launch_test(test/my_test.py
  ENV FASTDDS_BUILTIN_TRANSPORTS=UDPv4
)

Alternative: Switch to CycloneDDS:

export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp

Source: ROS Answers: DDS discovery not working on same machine

3. Missing Domain ID Isolation

Cause: Using add_launch_test without isolation can cause cross-talk between parallel tests.

Fix: Use add_ros_isolated_launch_test for unique ROS_DOMAIN_ID per test.

# In CMakeLists.txt
find_package(ament_cmake_ros REQUIRED)

function(add_ros_isolated_launch_test path)
  set(RUNNER "${ament_cmake_ros_DIR}/run_test_isolated.py")
  add_launch_test("${path}" RUNNER "${RUNNER}" ${ARGN})
endfunction()

add_ros_isolated_launch_test(test/my_integration_test.py
  TIMEOUT 180
)

Source: ROS2 Integration Testing Docs

4. QoS Profile Mismatch

Cause: Incompatible QoS profiles between publisher and subscriber silently prevent message delivery.

Debug:

ros2 topic info /my_topic -v  # Shows QoS of all publishers/subscribers

Fix: Ensure QoS compatibility. Common issues:

• RELIABLE subscriber cannot receive from BEST_EFFORT publisher
• TRANSIENT_LOCAL durability mismatch

Source: ROS2 QoS Documentation

Complete CMakeLists.txt Example

if(BUILD_TESTING)
  find_package(ament_cmake_pytest REQUIRED)
  find_package(ament_cmake_ros REQUIRED)
  find_package(launch_testing_ament_cmake REQUIRED)

  # Unit tests (no ROS dependencies)
  ament_add_pytest_test(test_my_module
    ${CMAKE_CURRENT_SOURCE_DIR}/tests/test_my_module.py
    TIMEOUT 120
    ENV PYTEST_DISABLE_PLUGIN_AUTOLOAD=1  # Avoid launch_testing import issues
  )

  # Define isolated launch test function
  function(add_ros_isolated_launch_test path)
    set(RUNNER "${ament_cmake_ros_DIR}/run_test_isolated.py")
    add_launch_test("${path}" RUNNER "${RUNNER}" ${ARGN})
  endfunction()

  # Integration test with DDS fixes
  add_ros_isolated_launch_test(test/test_integration.py
    TIMEOUT 180
    ENV FASTDDS_BUILTIN_TRANSPORTS=UDPv4
  )
endif()

Complete Test File Pattern

import os
import subprocess
import unittest

import rclpy
from rclpy.node import Node
from rclpy.executors import SingleThreadedExecutor

import launch
import launch_ros
import launch_testing

def generate_test_description():
    # Stop daemon to avoid RMW mismatch
    subprocess.run(['ros2', 'daemon', 'stop'], capture_output=True)

    # Force UDPv4 transport
    os.environ['FASTDDS_BUILTIN_TRANSPORTS'] = 'UDPv4'

    node_under_test = launch_ros.actions.Node(
        package='my_package',
        executable='my_node',
        name='my_node',
    )

    return (
        launch.LaunchDescription([
            node_under_test,
            launch_testing.actions.ReadyToTest(),
        ]),
        {'node_under_test': node_under_test}
    )

class TestIntegration(unittest.TestCase):
    @classmethod
    def setUpClass(cls):
        # Also stop daemon here in case generate_test_description ran in different process
        subprocess.run(['ros2', 'daemon', 'stop'], capture_output=True)

        try:
            rclpy.init()
        except RuntimeError:
            pass  # Already initialized

        cls.node = Node('test_node')
        cls.executor = SingleThreadedExecutor()
        cls.executor.add_node(cls.node)

    @classmethod
    def tearDownClass(cls):
        cls.executor.shutdown()
        cls.node.destroy_node()

    def test_something(self):
        # Your test here
        pass

Debugging Tips

1. Check if daemon is running:

   ros2 daemon status

2. Check RMW implementation:

   echo $RMW_IMPLEMENTATION
   ros2 doctor --report | grep middleware

3. List all topics with QoS:

   ros2 topic list -v
   ros2 topic info /my_topic -v

4. Test DDS discovery manually:

   # Terminal 1
   ros2 topic pub /test std_msgs/String "data: hello"
   
   # Terminal 2
   ros2 topic echo /test

5. Force different DDS:

   RMW_IMPLEMENTATION=rmw_cyclonedds_cpp ros2 topic list

References

• ROS2 Integration Testing Tutorial
• launch_testing GitHub
• FastDDS Builtin Transports
• ROS2 QoS Settings