added testcase for namespace

Signed-off-by: Markus Kramer <[email protected]>

Author: kramer-sim

launch_ros/test/test_cli_namespace.py

@@ -0,0 +1,62 @@
+#!/usr/bin/env python3
+
+# Copyright 2025 Open Source Robotics Foundation, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import unittest
+import subprocess
+
+class TestNamespaceArgument(unittest.TestCase):
+    """Test the --namespace command line argument for ros2 launch."""
+
+    def test_namespace_argument(self):
+        """Test that the --namespace argument correctly namespaces topics."""
+        try:
+            # Start the talker_listener launch file with namespace argument
+            launch_proc_remapped = subprocess.Popen(
+                ['ros2', 'launch', 'demo_nodes_cpp', 'talker_listener_launch.py', 
+                 '--namespace', 'test_namespace'],
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE
+            )
+
+            # Run ros2 topic list to get the remapped topics
+            result = subprocess.run(['ros2', 'topic', 'list'], 
+                                  stdout=subprocess.PIPE, 
+                                  stderr=subprocess.PIPE, 
+                                  text=True, 
+                                  check=True)
+            remapped_topics = result.stdout.strip().split('\n')
+
+            # Verify /chatter is NOT in the list
+            self.assertNotIn('/chatter', remapped_topics, 
+                           f"Did not expect to find /chatter after remapping. Topics: {remapped_topics}")
+
+            # Verify /test_namespace/chatter IS in the list
+            self.assertIn('/test_namespace/chatter', remapped_topics, 
+                        f"Expected to find /test_namespace/chatter after remapping. Topics: {remapped_topics}")
+
+        finally:
+            # Clean up
+            if 'launch_proc_remapped' in locals():
+                launch_proc_remapped.terminate()
+                try:
+                    launch_proc_remapped.wait(timeout=5)
+                except subprocess.TimeoutExpired:
+                    launch_proc_remapped.kill()
+                    launch_proc_remapped.wait()
+
+
+if __name__ == '__main__':
+    unittest.main()