Julia VS code custom task

Hello, I am trying to setup a vs code task to run a Julia extension command in the active VS code REPL.

What I hope to achieve is to bind a hotkey to a task that will run the runtest.jl file in the currently active REPL. I want to use this instead of the existing “Julia: Run Tests” (ctrl+shift+t) task because the existing task starts in a new REPL and takes ages to run on my machine.

What I have now is following:

    "version": "2.0.0",
    "tasks": [
            "command": "language-julia.executeFile",
            "args": [
            "label": "julia: Run runtest.jl in REPL"

but I get Unable to resolve filesystem provider with relative file path '' when I try to run it.

I asked about this previously on slack (question and answer are now gone from there), and someone made a pull request for executeFile to accept strings as well as uris. I am unsure whether that is part of the published extension and whether that is what is causing the error, as I have no clue how to debug this.

My failing task is based on the docs here and here.

Pretty sure that change to executeFile is only in the insiders builds. Can you give the most recent one a shot?

In the insider build, new shell is opened and the following message appears:

> Executing task: language-julia.executeFile /mnt/c/Users/user/julia/MyProject/test/runtests.jl <

The terminal process failed to launch: Path to shell executable "language-julia.executeFile" does not exist.

Terminal will be reused by tasks, press any key to close it.

So I think I am not using the extension command properly in the task.
Looking at the VS code docs, I think I might have reused a wrong code snippet. As I understand it, custom task can either run as a shell command or start a new process? I am unsure how to connect the task to the running REPL…