From 903d7797a4cb591f95e2eb5eb462af4c08d13311 Mon Sep 17 00:00:00 2001
From: Boris Okner <boris.okner@gmail.com>
Date: Tue, 11 Jul 2023 09:13:55 -0400
Subject: [PATCH] Fix flaky test (disconnect on server side could result either
 in :closed or :einval depending on timing of send call)

---
 lib/mllp/client.ex                            | 13 +++++++------
 test/client_and_receiver_integration_test.exs | 12 ++++++++----
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/lib/mllp/client.ex b/lib/mllp/client.ex
index c85277c..638ea73 100644
--- a/lib/mllp/client.ex
+++ b/lib/mllp/client.ex
@@ -3,7 +3,7 @@ defmodule MLLP.ClientContract do
   MLLP.ClientContract provides the behavior implemented by MLLP.Client. It may be useful
   for testing in your own application with tools such as [`Mox`](https://hexdocs.pm/mox/)
   """
-  @type error_type :: :connect_failure | :send_error | :recv_error
+  @type error_type :: :tcp_error | :send_error | :recv_error
   @type error_reason :: :closed | :timeout | :no_socket | :inet.posix()
 
   @type client_error :: MLLP.Client.Error.t()
@@ -162,7 +162,7 @@ defmodule MLLP.Client do
             pid: nil,
             telemetry_module: nil,
             tcp: nil,
-            connect_failure: nil,
+            tcp_error: nil,
             host_string: nil,
             send_opts: %{},
             tls_opts: [],
@@ -404,7 +404,7 @@ defmodule MLLP.Client do
   end
 
   def disconnected({:call, from}, {:send, _message, _options}, state) do
-    actions = [{:reply, from, {:error, new_error(:send, state.connect_failure)}}]
+    actions = [{:reply, from, {:error, new_error(:send, state.tcp_error)}}]
     {:keep_state_and_data, actions}
   end
 
@@ -603,7 +603,7 @@ defmodule MLLP.Client do
     |> tap(fn state ->
       telemetry(
         :status,
-        %{status: :disconnected, error: format_error(reason), context: "send message failure"},
+        %{status: :disconnected, error: format_error(reason)},
         state
       )
     end)
@@ -645,6 +645,7 @@ defmodule MLLP.Client do
 
     state
     |> Map.put(:socket, nil)
+    |> Map.put(:tcp_error, error)
   end
 
   defp backoff_succeed(%State{backoff: nil} = state), do: state
@@ -665,7 +666,7 @@ defmodule MLLP.Client do
           |> backoff_succeed()
 
         telemetry(:status, %{status: :connected}, state1)
-        {:ok, %{state1 | socket: socket, connect_failure: nil}}
+        {:ok, %{state1 | socket: socket, tcp_error: nil}}
 
       {:error, reason} ->
         message = format_error(reason)
@@ -680,7 +681,7 @@ defmodule MLLP.Client do
         {:error,
          state
          |> maybe_update_reconnection_timeout()
-         |> Map.put(:connect_failure, reason)}
+         |> Map.put(:tcp_error, reason)}
     end
   end
 
diff --git a/test/client_and_receiver_integration_test.exs b/test/client_and_receiver_integration_test.exs
index 02454d3..ff4218d 100644
--- a/test/client_and_receiver_integration_test.exs
+++ b/test/client_and_receiver_integration_test.exs
@@ -221,10 +221,14 @@ defmodule ClientAndReceiverIntegrationTest do
       MLLP.Receiver.stop(port)
       refute Process.alive?(receiver_pid)
 
-      assert match?(
-               {:error, %Error{context: _, message: "connection closed"}},
-               MLLP.Client.send(client_pid, "Simple message")
-             )
+      {:error, %Error{context: context, message: message}} =
+        MLLP.Client.send(client_pid, "Simple message")
+
+      assert context in [:send, :recv]
+      assert message in [MLLP.Client.format_error(:closed), MLLP.Client.format_error(:einval)]
+
+      refute MLLP.Client.is_connected?(client_pid)
+
     end
 
     test "with a larger message" do