Use ROS extension's launch debugger while setting ROS_IP

[rsarrazin2]

We have a setup where we communicate between different machines (actually different docker containers) and a ROS1 launch file starts all nodes. When setting ROS_IP on the "launch" container and ROS_MASTER_URI on the other container, the communication works well and as expected.

Nevertheless, when starting the extension's launch debugger, the communication doesn't happen - as if ROS_IP hadn't been set. I set ROS_IP in the launch.json, here is how my configuration looks like:

        {
            "name": "ROS: Debug",
            "type": "ros",
            "request": "launch",
            "target": "${workspaceFolder}/src/package/package.launch",
            "arguments": [
                "param1:=value1",
                "param2:=value2"
            ],
            "env": {
                "ROS_IP": "172.17.177.140"
            }
        }

What am I missing? I guess the roscore is found by the other machine as there's no error message, but the messages sent from the "launch" machine don't reach the other machine as if ROS_IP wasn't set. What am I missing?

By the way, https://github.com/ms-iot/vscode-ros/blob/master/doc/debug-support.md#prerequisite seems to tell a roscore needs to be started manually, but it looks like one is started when debugging a launch file (and this is backed by

vscode-ros/src/debugger/configuration/resolvers/ros1/launch.ts

Line 49 in 43dc595

rosApi.startCore();

). Is the documentation referring to something else?