How to catch a termination in GenServer.cast?

Hello,

I’m trying to test that worker terminates via {:stop, reason, state} after a certain number of retries. My first attempt was to use Process.flag(:trap_exit, true)

test "worker termination after all retries failed", ctx do
  error = ~s<{"just": "because"}>
  {:ok, wrk}    = GenServer.start(Elastic.Worker, nil)

  Process.flag(:trap_exit, true)
  Application.put_env(:tirexs, :uri, endpoint_url(ctx.bypass.port))
  Bypass.expect(ctx.bypass, &Plug.Conn.send_resp(&1, 500, error))

  Elastic.Worker.insert(wrk, ctx.doc, Property)
  assert_receive {:EXIT, ^wrk, ^error}, 1000
end

it failed due to reason described here Trapping GenServer exits in ExUnit tests · Issue #3507 · elixir-lang/elixir · GitHub and then I tried to wrap operation in try/catch/rescue block

   {:ok, wrk} = GenServer.start(Elastic.Worker, nil)
      Elastic.Worker.insert(wrk, ctx.doc, Property)
      :timer.sleep(1000)
    rescue
      msg -> IO.inspect "rescued #{msg}"
    catch
      msg -> IO.inspect "catched #{msg}"
    end

No luck as well as with catch_exit and assert_raise:

assert catch_exit((fn ->
  {:ok, wrk} = GenServer.start(Elastic.Worker, nil)
  Elastic.Worker.insert(wrk, ctx.doc, Property)
  :timer.sleep(1000)
end).()) == 1

Error mesasge (and the reason) looks like that:

.12:10:03.513 [error] GenServer #PID<0.530.0> terminating
** (stop) {:error, 500, %{just: "because"}}