fails the test properly to avoid TypeError exception. (#1016)

Signed-off-by: Tomoya Fujita <[email protected]>

Author: fujitatomoya

ros2param/test/test_verb_load.py

@@ -344,8 +344,13 @@ def test_verb_load_wildcard(self):
             ) as param_dump_command:
                 assert param_dump_command.wait_for_shutdown(timeout=TEST_TIMEOUT)
             assert param_dump_command.exit_code == launch_testing.asserts.EXIT_OK
-            loaded_params = yaml.safe_load(param_dump_command.output)
-            params = loaded_params[f'{TEST_NAMESPACE}/{TEST_NODE}']['ros__parameters']
+            try:
+                loaded_params = yaml.safe_load(param_dump_command.output)
+                if not isinstance(loaded_params, dict):
+                    self.fail('Invalid YAML output: Expected a dictionary')
+                params = loaded_params[f'{TEST_NAMESPACE}/{TEST_NODE}']['ros__parameters']
+            except yaml.YAMLError as e:
+                self.fail(f'Failed to parse YAML output: {e}')
             assert params['str_param'] == 'Wildcard'
             assert params['int_param'] == 12345
 
@@ -365,8 +370,13 @@ def test_verb_load_wildcard(self):
             ) as param_dump_command:
                 assert param_dump_command.wait_for_shutdown(timeout=TEST_TIMEOUT)
             assert param_dump_command.exit_code == launch_testing.asserts.EXIT_OK
-            loaded_params = yaml.safe_load(param_dump_command.output)
-            params = loaded_params[f'{TEST_NAMESPACE}/{TEST_NODE}']['ros__parameters']
+            try:
+                loaded_params = yaml.safe_load(param_dump_command.output)
+                if not isinstance(loaded_params, dict):
+                    self.fail('Invalid YAML output: Expected a dictionary')
+                params = loaded_params[f'{TEST_NAMESPACE}/{TEST_NODE}']['ros__parameters']
+            except yaml.YAMLError as e:
+                self.fail(f'Failed to parse YAML output: {e}')
             assert params['str_param'] == 'Override'  # Overriden
             assert params['int_param'] == 12345  # Wildcard namespace
 
@@ -386,7 +396,12 @@ def test_verb_load_wildcard(self):
             ) as param_dump_command:
                 assert param_dump_command.wait_for_shutdown(timeout=TEST_TIMEOUT)
             assert param_dump_command.exit_code == launch_testing.asserts.EXIT_OK
-            loaded_params = yaml.safe_load(param_dump_command.output)
-            params = loaded_params[f'{TEST_NAMESPACE}/{TEST_NODE}']['ros__parameters']
+            try:
+                loaded_params = yaml.safe_load(param_dump_command.output)
+                if not isinstance(loaded_params, dict):
+                    self.fail('Invalid YAML output: Expected a dictionary')
+                params = loaded_params[f'{TEST_NAMESPACE}/{TEST_NODE}']['ros__parameters']
+            except yaml.YAMLError as e:
+                self.fail(f'Failed to parse YAML output: {e}')
             assert params['str_param'] == 'Override'  # Overriden
             assert params['int_param'] == 12345  # Wildcard namespace