Create tw5p empty for previous tw5 version

Just in case 5.4.0 has problems, let's support creating a site with
the latest-1 TW version. I decided not to add an equivalent for the
external tw5x version.

Author: simonbaird

rails/db/migrate/20260423152602_add_tw5p_empty.rb

@@ -0,0 +1,19 @@
+class AddTw5pEmpty < ActiveRecord::Migration[7.2]
+  def up
+    Empty.find_or_create_by(name: 'tw5p') do |e|
+      e.title = 'TiddlyWiki (previous version)'
+      e.description = 'The previous stable version of TiddlyWiki, with internal core javascript.'.squish
+      e.enabled = true
+      e.info_link = 'https://tiddlywiki.com/'
+      e.display_order = 39
+      e.primary = false
+      e.tooltip = "It's recommended to use the latest version, but this older
+        version is available if needed, e.g. for plugin compatibility reasons.".squish
+    end.update(enabled: true) # Make sure it's enabled in case you did a rollback
+  end
+
+  def down
+    # Disable it but don't delete it since there might be sites using it
+    Empty.find_by_name('tw5p').update(enabled: false)
+  end
+end

rails/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.0].define(version: 2026_04_21_202925) do
+ActiveRecord::Schema[8.0].define(version: 2026_04_23_152602) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_catalog.plpgsql"
 

rails/db/seeds/empties.yml

@@ -88,3 +88,13 @@
   info_link: https://alamantus.codeberg.page/siteleteer/
   tooltip: To see how it works, view the clean and very readable page source. Requires
     a custom build of siteleteer.
+- id: 22
+  name: tw5p
+  title: TiddlyWiki (previous version)
+  description: The previous stable version of TiddlyWiki, with internal core javascript.
+  enabled: true
+  display_order: 11
+  primary: false
+  info_link: https://tiddlywiki.com/
+  tooltip: It's recommended to use the latest version, but this older version is available
+    if you need it, e.g. for plugin compatibility reasons.

rails/test/fixtures/empties.yml

@@ -73,3 +73,14 @@ sitelet:
   info_link: https://alamantus.codeberg.page/siteleteer/
   tooltip: To see how it works, view the clean and very readable page source. Requires
     a custom build of siteleteer.
+tw5p:
+  id: 22
+  name: tw5p
+  title: TiddlyWiki (previous version)
+  description: The previous stable version of TiddlyWiki, with internal core javascript.
+  enabled: true
+  display_order: 39
+  primary: false
+  info_link: https://tiddlywiki.com/
+  tooltip: It's recommended to use the latest version, but this older version is available
+    if needed, e.g. for plugin compatibility reasons.

rails/test/models/tw_file_test.rb

@@ -153,6 +153,10 @@ class TwFileTest < ActiveSupport::TestCase
 
       empty = Empty.find_by_name(tw_kind)
       assert empty, "No empty found for kind #{tw_kind}!"
+
+      # tw5p is the same kind as tw5, just a different version
+      next if tw_kind == "tw5p"
+
       assert_equal(tw_kind, empty.kind, "Derived kind was #{empty.kind}, expecting #{tw_kind}!")
     end
   end