Use of -r/--remap flags where appropriate.

[hidmic]

Precisely what the title says.

Connected to ros2/rcl#491.

[ivanpauno]

The patch is not correct, you have to modify the local substitutions here:

launch_ros/launch_ros/launch_ros/actions/node.py

Lines 348 to 363 in d10cb9e

	if self.__node_name is not None:
	ros_specific_arguments['name'] = '__node:={}'.format(self.__expanded_node_name)
	if self.__expanded_node_namespace != '':
	ros_specific_arguments['ns'] = '__ns:={}'.format(self.__expanded_node_namespace)
	if self.__expanded_parameter_files is not None:
	ros_specific_arguments['params'] = []
	param_arguments = cast(List[str], ros_specific_arguments['params'])
	for param_file_path in self.__expanded_parameter_files:
	param_arguments.append('__params:={}'.format(param_file_path))
	if self.__expanded_remappings is not None:
	ros_specific_arguments['remaps'] = []
	for remapping_from, remapping_to in self.__expanded_remappings:
	remap_arguments = cast(List[str], ros_specific_arguments['remaps'])
	remap_arguments.append(
	'{}:={}'.format(remapping_from, remapping_to)
	)

[hidmic]

That was actually a tradeoff solution. Functionally it works the same way as if local substitutions had been updated, though it renders ros_specific_arguments incomplete, so much is true. Problem is, substitutions do not expand to List[Text] nor we have support for tokenizing cmd (ros2/launch#263), and I purposefully wanted to keep these changes scoped.

Once ros2/launch#263 is there, yes, we can change this.

[ivanpauno]

That was actually a tradeoff solution. Functionally it works the same way as if local substitutions had been updated, though it renders ros_specific_arguments incomplete, so much is true. Problem is, substitutions do not expand to List[Text] nor we have support for tokenizing cmd (ros2/launch#263), and I purposefully wanted to keep these changes scoped.

Ok, I understand.
I first thought that the following was possible:

• '-r' + local substitution added to the command.
• local substitution is replaced for an empty string, and then remapping rule parsing fails.

But after reading this for a second time, I think that that isn't possible.