refactor

lib/mv_web/live/import_export_live.ex

@@ -45,6 +45,9 @@ defmodule MvWeb.ImportExportLive do
   # after this limit is reached.
   @max_errors 50
 
+  # Maximum length for error messages before truncation
+  @max_error_message_length 200
+
   @impl true
   def mount(_params, session, socket) do
     # Get locale from session for translations
@@ -95,11 +98,11 @@ defmodule MvWeb.ImportExportLive do
       <%= if Authorization.can?(@current_user, :create, Mv.Membership.Member) do %>
         <%!-- CSV Import Section --%>
         <.form_section title={gettext("Import Members (CSV)")}>
-          <%= import_info_box(assigns) %>
-          <%= template_links(assigns) %>
-          <%= import_form(assigns) %>
+          {import_info_box(assigns)}
+          {template_links(assigns)}
+          {import_form(assigns)}
           <%= if @import_status == :running or @import_status == :done do %>
-            <%= import_progress(assigns) %>
+            {import_progress(assigns)}
           <% end %>
         </.form_section>
 
@@ -243,7 +246,7 @@ defmodule MvWeb.ImportExportLive do
         <% end %>
 
         <%= if @import_progress.status == :done do %>
-          <%= import_results(assigns) %>
+          {import_results(assigns)}
         <% end %>
       </div>
     <% end %>
@@ -487,9 +490,7 @@ defmodule MvWeb.ImportExportLive do
 
   # Formats Ash validation errors for display
   defp format_ash_error(%Ash.Error.Invalid{errors: errors}) when is_list(errors) do
-    errors
-    |> Enum.map(&format_single_error/1)
-    |> Enum.join(", ")
+    Enum.map_join(errors, ", ", &format_single_error/1)
   end
 
   defp format_ash_error(error) do
@@ -498,9 +499,7 @@ defmodule MvWeb.ImportExportLive do
 
   # Formats a list of errors into a readable string
   defp format_error_list(errors) do
-    errors
-    |> Enum.map(&format_single_error/1)
-    |> Enum.join(", ")
+    Enum.map_join(errors, ", ", &format_single_error/1)
   end
 
   # Formats a single error item
@@ -516,8 +515,8 @@ defmodule MvWeb.ImportExportLive do
   defp format_unknown_error(other) do
     error_str = inspect(other, limit: :infinity, pretty: true)
 
-    if String.length(error_str) > 200 do
-      String.slice(error_str, 0, 197) <> "..."
+    if String.length(error_str) > @max_error_message_length do
+      String.slice(error_str, 0, @max_error_message_length - 3) <> "..."
     else
       error_str
     end
@@ -558,6 +557,49 @@ defmodule MvWeb.ImportExportLive do
     handle_chunk_error(socket, :processing_failed, idx, reason)
   end
 
+  # Processes a chunk with error handling and sends result message to LiveView.
+  #
+  # Handles errors from MemberCSV.process_chunk and sends appropriate messages
+  # to the LiveView process for progress tracking.
+  @spec process_chunk_with_error_handling(
+          list(),
+          map(),
+          map(),
+          keyword(),
+          pid(),
+          non_neg_integer()
+        ) :: :ok
+  defp process_chunk_with_error_handling(
+         chunk,
+         column_map,
+         custom_field_map,
+         opts,
+         live_view_pid,
+         idx
+       ) do
+    result =
+      try do
+        MemberCSV.process_chunk(chunk, column_map, custom_field_map, opts)
+      rescue
+        e ->
+          {:error, Exception.message(e)}
+      catch
+        :exit, reason ->
+          {:error, inspect(reason)}
+
+        :throw, reason ->
+          {:error, inspect(reason)}
+      end
+
+    case result do
+      {:ok, chunk_result} ->
+        send(live_view_pid, {:chunk_done, idx, chunk_result})
+
+      {:error, reason} ->
+        send(live_view_pid, {:chunk_error, idx, reason})
+    end
+  end
+
   # Starts async task to process a chunk of CSV rows.
   #
   # In tests (SQL sandbox mode), runs synchronously to avoid Ecto Sandbox issues.
@@ -586,33 +628,16 @@ defmodule MvWeb.ImportExportLive do
 
     if Config.sql_sandbox?() do
       # Run synchronously in tests to avoid Ecto Sandbox issues with async tasks
-      result =
-        try do
-          MemberCSV.process_chunk(
-            chunk,
-            import_state.column_map,
-            import_state.custom_field_map,
-            opts
-          )
-        rescue
-          e ->
-            {:error, Exception.message(e)}
-        catch
-          :exit, reason ->
-            {:error, inspect(reason)}
-          :throw, reason ->
-            {:error, inspect(reason)}
-        end
-
-      case result do
-        {:ok, chunk_result} ->
-          # In test mode, send the message - it will be processed when render() is called
-          # in the test. The test helper wait_for_import_completion() handles message processing
-          send(live_view_pid, {:chunk_done, idx, chunk_result})
-
-        {:error, reason} ->
-          send(live_view_pid, {:chunk_error, idx, reason})
-      end
+      # In test mode, send the message - it will be processed when render() is called
+      # in the test. The test helper wait_for_import_completion() handles message processing
+      process_chunk_with_error_handling(
+        chunk,
+        import_state.column_map,
+        import_state.custom_field_map,
+        opts,
+        live_view_pid,
+        idx
+      )
     else
       # Start async task to process chunk in production
       # Use start_child for fire-and-forget: no monitor, no Task messages
@@ -621,31 +646,14 @@ defmodule MvWeb.ImportExportLive do
         # Set locale in task process for translations
         Gettext.put_locale(MvWeb.Gettext, locale)
 
-        result =
-          try do
-            MemberCSV.process_chunk(
-              chunk,
-              import_state.column_map,
-              import_state.custom_field_map,
-              opts
-            )
-          rescue
-            e ->
-              {:error, Exception.message(e)}
-          catch
-            :exit, reason ->
-              {:error, inspect(reason)}
-            :throw, reason ->
-              {:error, inspect(reason)}
-          end
-
-        case result do
-          {:ok, chunk_result} ->
-            send(live_view_pid, {:chunk_done, idx, chunk_result})
-
-          {:error, reason} ->
-            send(live_view_pid, {:chunk_error, idx, reason})
-        end
+        process_chunk_with_error_handling(
+          chunk,
+          import_state.column_map,
+          import_state.custom_field_map,
+          opts,
+          live_view_pid,
+          idx
+        )
       end)
     end
 
@@ -712,8 +720,14 @@ defmodule MvWeb.ImportExportLive do
   @spec consume_and_read_csv(Phoenix.LiveView.Socket.t()) ::
           {:ok, String.t()} | {:error, String.t()}
   defp consume_and_read_csv(socket) do
-    case consume_uploaded_entries(socket, :csv_file, &read_file_entry/2) do
-      [{:ok, content}] ->
+    raw = consume_uploaded_entries(socket, :csv_file, &read_file_entry/2)
+
+    case raw do
+      [{:ok, content}] when is_binary(content) ->
+        {:ok, content}
+
+      # Phoenix LiveView test (render_upload) can return raw content list when callback return is treated as value
+      [content] when is_binary(content) ->
         {:ok, content}
 
       [{:error, reason}] ->