add yaml dumper representator for str type to keep quotes always. (#436)

* add yaml dumper representator for str type to keep quotes always.

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

* representator should be applied to conversion from py dictionary.

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

---------

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

Author: fujitatomoya

Diff for: launch_ros/launch_ros/actions/node.py

@@ -373,6 +373,10 @@ def _create_params_file_from_dict(self, params):
                 self.node_name if self.is_node_name_fully_specified() else '/**':
                 {'ros__parameters': params}
             }
+
+            def quoted_representor(dumper, data):
+                return dumper.represent_scalar('tag:yaml.org,2002:str', data, style='"')
+            yaml.add_representer(str, quoted_representor)
             yaml.dump(param_dict, h, default_flow_style=False)
             return param_file_path