Support older put_root_layouts API

lib/mix/tasks/lvn.setup.config.ex

@@ -527,7 +527,12 @@ defmodule Mix.Tasks.Lvn.Setup.Config do
 
       %{node: {:plug, _, [{:__block__, _, [:put_root_layout]}, quoted_root_layouts]} = quoted_plug}->
         range = Sourceror.get_range(quoted_plug)
-        old_root_layouts = Code.eval_quoted(quoted_root_layouts) |> elem(0)
+        old_root_layouts =
+          (Code.eval_quoted(quoted_root_layouts) |> elem(0))
+          |> case do
+            old_root_layout when is_tuple(old_root_layout) -> [html: old_root_layout]
+            old_root_layouts -> old_root_layouts
+          end
 
         root_layouts =
           (old_root_layouts ++ new_root_layouts)

test/mix/tasks/lvn.setup_test.exs

@@ -320,7 +320,7 @@ defmodule Mix.Tasks.Lvn.SetupTest do
         """
     end
 
-    test "when :phonex config exists the :template_engines list is updated and duplicates are removed" do
+    test "when :phoenix config exists the :template_engines list is updated and duplicates are removed" do
       config = """
         config :phoenix, :template_engines, [
           other: Other.Engine,
@@ -337,4 +337,39 @@ defmodule Mix.Tasks.Lvn.SetupTest do
         """
     end
   end
+
+  describe "router codgen scenarios" do
+    test "patch_layouts when this old style of router layout option is being used, rewrite as the new keyword list with html" do
+      config = """
+          pipeline :browser do
+            plug :accepts, ["html"]
+            plug :fetch_session
+            plug :fetch_live_flash
+
+            plug :put_root_layout, {LiveViewNativeWeb.Layouts, :root}
+
+            plug :protect_from_forgery
+            plug :put_secure_browser_headers
+          end
+        """
+
+      {_, {result, _}} = Config.patch_root_layouts({%{}, {config, "live_view_native_web/router.ex"}})
+
+      assert result =~ """
+        pipeline :browser do
+          plug :accepts, ["html"]
+          plug :fetch_session
+          plug :fetch_live_flash
+
+          plug :put_root_layout,
+            gameboy: {LiveViewNativeWeb.Layouts.GameBoy, :root},
+            html: {LiveViewNativeWeb.Layouts, :root},
+            switch: {LiveViewNativeWeb.Layouts.Switch, :root}
+
+          plug :protect_from_forgery
+          plug :put_secure_browser_headers
+        end
+      """
+    end
+  end
 end