Don't run LastFm.Feed in tests

lib/last_fm/api_behaviour.ex

@@ -0,0 +1,7 @@
+defmodule LastFm.APIBehaviour do
+  alias LastFm.Track
+
+  @type user :: String.t()
+  @type api_key :: String.t()
+  @callback get_recent_tracks(user, api_key) :: {:ok, [%Track{}]} | {:error, String.t()}
+end

lib/last_fm/api_impl.ex

@@ -1,10 +1,13 @@
-defmodule LastFm.API do
+defmodule LastFm.APIImpl do
+  @behaviour LastFm.APIBehaviour
+
   require Logger
 
   alias LastFm.Track
 
   @base_url "http://ws.audioscrobbler.com/2.0/"
 
+  @impl true
   def get_recent_tracks(user, api_key) do
     options = [
       method: "user.getrecenttracks",

lib/last_fm/refresh.ex

@@ -3,7 +3,7 @@ defmodule LastFm.Refresh do
 
   require Logger
 
-  alias LastFm.{API, Feed}
+  alias LastFm.Feed
 
   @refresh_interval System.convert_time_unit(30, :second, :millisecond)
 
@@ -12,7 +12,7 @@ defmodule LastFm.Refresh do
   end
 
   def init(config) do
-    if config.api_key do
+    if enabled?(config) do
       {:ok, config, {:continue, :refresh}}
     else
       :ignore
@@ -20,7 +20,7 @@ defmodule LastFm.Refresh do
   end
 
   def handle_continue(:refresh, config) do
-    case API.get_recent_tracks(config.user, config.api_key) do
+    case config.api.get_recent_tracks(config.user, config.api_key) do
       {:ok, tracks} ->
         Feed.update(tracks)
         Process.send_after(self(), :refresh, @refresh_interval)
@@ -32,4 +32,8 @@ defmodule LastFm.Refresh do
         {:noreply, config}
     end
   end
+
+  defp enabled?(config) do
+    config.api && config.api_key
+  end
 end

lib/last_fm/supervisor.ex

@@ -6,11 +6,15 @@ defmodule LastFm.Supervisor do
   end
 
   @impl true
-  def init(_init_arg) do
+  def init(opts) do
     :ok = LastFm.Feed.create_table!()
 
+    api =
+      Keyword.fetch!(opts, :api)
+      |> IO.inspect()
+
     children = [
-      {LastFm.Refresh, %{user: "cloud8421", api_key: api_key()}}
+      {LastFm.Refresh, %{api: api, user: "cloud8421", api_key: api_key()}}
     ]
 
     Supervisor.init(children, strategy: :one_for_one)