Trying to understand the fetch_state event handler

[brianmay]

What does this code do?

  def handle_event(:internal, :fetch_state, _state, %Data{car: car} = data) do
    Task.async(fn ->
      with {:ok, %Vehicle{state: state} = vehicle} when is_binary(state) <-
             call(data.deps.api, :get_vehicle, [car.eid]) do
        {String.to_existing_atom(state), vehicle}
      end
    end)

    :keep_state_and_data
  end

To me it looks we are starting a new process, retrieving data from the car, and then completely discarding the result. We are not even keeping track of the task. Surely this can't be right?

It looks like this gets called when the stream becomes inactive, and the car is suspended.

Similarly, the data from retrieved from the following function:

  def handle_event(event, :fetch, state, %Data{task: nil} = data)
      when event in [:state_timeout, :internal] do
    task =
      Task.async(fn ->
        fetch(data, expected_state: state)
      end)

    {:keep_state, %Data{data | task: task}, broadcast_fetch(true)}
  end

Some how ends up here:

def handle_event(:info, {ref, fetch_result}, state, %Data{task: %Task{ref: ref}} = data)

Not sure I understand how this happens. But if I understand this, might help to explain the first question.