Bug fix: switch to :disconnected if conn has closed

lib/mllp/client.ex

@@ -542,7 +542,7 @@ defmodule MLLP.Client do
   def receiving(:info, {transport, socket, incoming}, %{socket: socket} = data)
       when transport in [:tcp, :ssl] do
     new_data = handle_received(incoming, data)
-    next_state = (new_data.caller && :receiving) || :connected
+    next_state = next_after_receiving(new_data)
     {:next_state, next_state, new_data}
   end
 
@@ -565,6 +565,18 @@ defmodule MLLP.Client do
     unexpected_message(:receiving, event, unknown)
   end
 
+  defp next_after_receiving(%State{socket: nil}) do
+    :disconnected
+  end
+
+  defp next_after_receiving(%State{caller: nil}) do
+    :connected
+  end
+
+  defp next_after_receiving(%State{} = _state) do
+    :receiving
+  end
+
   ########################################
   ### End of :gen_statem callbacks ###
   ########################################
@@ -707,7 +719,7 @@ defmodule MLLP.Client do
       data
     )
 
-    Logger.debug("Stopping connection: #{format_error(error)}}")
+    Logger.debug("Stopping connection: #{format_error(error)}")
 
     if error == :unexpected_packet_received do
       :ok = :inet.setopts(socket, linger: {true, 0})

test/client_test.exs

@@ -175,13 +175,20 @@ defmodule ClientTest do
       log =
         capture_log([level: :debug], fn ->
           Kernel.send(pid, {:tcp, socket, "what's up?"})
-          Process.sleep(100)
+
+          {:error, _} =
+            Client.send(
+              pid,
+              "this should fail as the connection will be dropped on unexpected packet"
+            )
+
+          refute Client.is_connected?(pid)
+          Client.reconnect(pid)
+          {:ok, _} = Client.send(pid, "ok")
         end)
 
       assert String.contains?(log, Client.format_error(:unexpected_packet_received))
       assert String.contains?(log, "Connection closed")
-
-      refute Client.is_connected?(pid)
     end
   end