Add launch test using ros parameter (#29)

---------

Co-authored-by: Bilal Gill <[email protected]>

functional_programming_tests/CMakeLists.txt

@@ -17,6 +17,7 @@ ament_target_dependencies(main rclcpp std_msgs example_srvs)
 if(BUILD_TESTING)
   find_package(ament_cmake_gtest REQUIRED)
   find_package(ament_cmake_gmock REQUIRED)
+  find_package(launch_testing_ament_cmake REQUIRED)
   ament_add_gtest(with_functional_programming test/with_functional_programming.cpp TIMEOUT 5)
   ament_target_dependencies(with_functional_programming rclcpp std_msgs)
 
@@ -25,6 +26,10 @@ if(BUILD_TESTING)
 
   ament_add_gmock(with_dependency_injection test/with_dependency_injection.cpp TIMEOUT 5)
   ament_target_dependencies(with_dependency_injection rclcpp std_msgs example_srvs)
+
+  ament_add_gtest_executable(with_parameters test/with_parameters.cpp)
+  ament_target_dependencies(with_parameters rclcpp std_msgs example_srvs)
+  add_launch_test(test/launch/with_parameters.test.py TIMEOUT 120 ARGS "test_binary_dir:=${CMAKE_CURRENT_BINARY_DIR}")
 endif()
 
 ament_package()

functional_programming_tests/test/launch/with_parameters.test.py

@@ -0,0 +1,54 @@
+# -*- coding: utf-8 -*-
+import launch
+from launch_ros.actions import Node
+import launch_testing
+import unittest
+
+
+def generate_test_description():
+
+    with_parameters_test = Node(
+        executable=launch.substitutions.PathJoinSubstitution(
+            [
+                launch.substitutions.LaunchConfiguration("test_binary_dir"),
+                "with_parameters",
+            ]
+        ),
+        output="screen",
+        emulate_tty=True,
+        parameters=[
+            {"robot_size": 1},
+        ],
+    )
+
+    return launch.LaunchDescription(
+        [
+            launch.actions.DeclareLaunchArgument(
+                name="test_binary_dir",
+                description="Binary directory of package "
+                "containing test executables",
+            ),
+            with_parameters_test,
+            # In tests where all of the procs under tests terminate themselves, it's necessary
+            # to add a dummy process not under test to keep the launch alive. launch_test
+            # provides a simple launch action that does this:
+            # https://github.com/ros2/launch/blob/aed025e04e0b143362c69bf29a67b2ffff4c59ee/launch_testing/test/launch_testing/examples/args_launch_test.py#L63
+            launch_testing.util.KeepAliveProc(),
+            launch_testing.actions.ReadyToTest(),
+        ]
+    ), {
+        "with_parameters_test": with_parameters_test,
+    }
+
+
+class TestGTestWaitForCompletion(unittest.TestCase):
+    # Waits for test to complete, then waits a bit to make sure result files are generated
+    def test_gtest_run_complete(self, with_parameters_test):
+        self.proc_info.assertWaitForShutdown(with_parameters_test, timeout=4000.0)
+
+
+@launch_testing.post_shutdown_test()
+class TestGTestProcessPostShutdown(unittest.TestCase):
+    # Checks if the test has been completed with acceptable exit codes
+    def test_gtest_pass(self, proc_info, with_parameters_test):
+        launch_testing.asserts.assertExitCodes(proc_info, process=with_parameters_test)