From 87d2134c634709c6a372144fb507251b25032d2d Mon Sep 17 00:00:00 2001
From: Old-Ding <35417409+Old-Ding@users.noreply.github.com>
Date: Sat, 11 Jul 2026 15:27:54 +0800
Subject: [PATCH] Fix string representations for untyped parameters

ParameterValue and Parameter default value_type to None, but their string representations unconditionally accessed __name__. Render the default type as None and cover both public description classes.

Signed-off-by: Old-Ding <35417409+Old-Ding@users.noreply.github.com>
---
 launch_ros/launch_ros/parameter_descriptions.py             | 6 ++++--
 .../test/test_launch_ros/descriptions/test_parameter.py     | 3 +++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/launch_ros/launch_ros/parameter_descriptions.py b/launch_ros/launch_ros/parameter_descriptions.py
index 46f226d3..80ffc51a 100644
--- a/launch_ros/launch_ros/parameter_descriptions.py
+++ b/launch_ros/launch_ros/parameter_descriptions.py
@@ -81,9 +81,10 @@ def value_type(self) -> AllowedTypesType:
         return self.__value_type
 
     def __str__(self) -> Text:
+        value_type_name = self.value_type.__name__ if self.value_type is not None else None
         return (
             'launch_ros.description.ParameterValue'
-            f'(value={self.value}, value_type={self.value_type.__name__})'
+            f'(value={self.value}, value_type={value_type_name})'
         )
 
     def evaluate(self, context: LaunchContext) -> 'EvaluatedParameterValue':
@@ -146,9 +147,10 @@ def value_type(self) -> AllowedTypesType:
         return self.__parameter_value.value_type
 
     def __str__(self) -> Text:
+        value_type_name = self.value_type.__name__ if self.value_type is not None else None
         return (
             'launch_ros.description.Parameter'
-            f'(name={self.name}, value={self.value}, value_type={self.value_type.__name__})'
+            f'(name={self.name}, value={self.value}, value_type={value_type_name})'
         )
 
     def evaluate(self, context: LaunchContext) -> Tuple[Text, 'EvaluatedParameterValue']:
diff --git a/test_launch_ros/test/test_launch_ros/descriptions/test_parameter.py b/test_launch_ros/test/test_launch_ros/descriptions/test_parameter.py
index db3c3a32..73ad7952 100644
--- a/test_launch_ros/test/test_launch_ros/descriptions/test_parameter.py
+++ b/test_launch_ros/test/test_launch_ros/descriptions/test_parameter.py
@@ -40,6 +40,7 @@ def test_parameter_value_description():
     param = ParameterValue(value='asd')
     assert param.value == 'asd'
     assert param.value_type is None
+    assert str(param) == 'launch_ros.description.ParameterValue(value=asd, value_type=None)'
     assert param.evaluate(lc) == 'asd'
     # After the first `evaluate` call, the following `.value` and `.evaluate()`
     # calls are calculated differently. Test them too.
@@ -107,6 +108,8 @@ def test_parameter_description():
     assert param.value == 'asd'
     assert param.value_type is None
     assert param.evaluate(lc) == ('my_param', 'asd')
+    assert str(param) == (
+        'launch_ros.description.Parameter(name=my_param, value=asd, value_type=None)')
     # After the first `evaluate` call, the following `.name` `.value` and `.evaluate()`
     # calls are calculated differently. Test them too.
     assert param.name == 'my_param'