Debugger does not stop at the breakpoint

[dehlong]

Hello,
when I try to run the step debugger, breakpoints just get ignored and it finishes without breaking. I have the default setup and I try to debug quicksort.

Here is my launch.json:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "type": "mix_task",
            "name": "mix (Default task)",
            "request": "launch",
            "projectDir": "${workspaceRoot}",
        },
        {
            "type": "mix_task",
            "name": "mix test",
            "request": "launch",
            "task": "test",
            "taskArgs": [
                "--trace"
            ],
            "startApps": true,
            "projectDir": "${workspaceRoot}",
            "requireFiles": [
                "test/**/test_helper.exs",
                "test/**/*_test.exs"
            ]
        }
    ]
}

And this is what the debugger prints:

Setting breakpoint in QuickSort /home/samo/Documents/Programming/elixir_test/lib/elixir_test.ex:12
Running mix run
Mix.Task.run returned:
:ok
Exiting debugger.
If this behavior is undesired consider setting `exitAfterTaskReturns` to `false` in launch config.
Mix task exited with reason
normal
returning code 0
Mix task exited with reason
normal
returning code 0
Received disconnect request

And this happens no matter whether I have breakpoints set or not.

[lukaszsamson]

Please share a repro and fill issue details

[dehlong]

Elixir & Erlang versions (elixir --version): Erlang/OTP 28 [erts-16.3.1] [source] [64-bit] [smp:16:16] [ds:16:16:10] [async-threads:1] [jit:ns], Elixir 1.19.5 (compiled with Erlang/OTP 28)
VSCode ElixirLS version: 0.30.0
Operating System Version: Arch Linux

Reproduction steps:

1. Create a new elixir project.
2. Create a launch.json file with the default settings as I showed before
3. Create a basic elixir program, such as quicksort:

defmodule QuickSort do
  @spec sort(maybe_improper_list()) :: list()
  def sort([]), do: []

  def sort([pivot | rest]) do
    left = for x <- rest, x <= pivot, do: x
    right = for x <- rest, x > pivot, do: x

    sort(left) ++ [pivot] ++ sort(right)
  end
end

4. Set a breakpoint to any line
5. Hit F5, the debugger will start the program but end immediately.