Migrate to new theming infrastructure (#37612)

.storybook/preview.tsx

@@ -21,9 +21,7 @@ import { reducerWithInitialState } from '@/mastodon/reducers';
 import { defaultMiddleware } from '@/mastodon/store/store';
 import { mockHandlers, unhandledRequestHandler } from '@/testing/api';
 
-// If you want to run the dark theme during development,
-// you can change the below to `/application.scss`
-import '../app/javascript/styles/mastodon-light.scss';
+import '../app/javascript/styles/application.scss';
 import './styles.css';
 import { modes } from './modes';
 

app/controllers/application_controller.rb

@@ -180,22 +180,11 @@ class ApplicationController < ActionController::Base
   end
 
   def color_scheme
-    current = current_user&.setting_color_scheme
-    return current if current && current != 'auto'
-
-    return 'dark' if current_theme.include?('default') || current_theme.include?('contrast')
-    return 'light' if current_theme.include?('light')
-
-    'auto'
+    current_user&.setting_color_scheme || 'auto'
   end
 
   def contrast
-    current = current_user&.setting_contrast
-    return current if current && current != 'auto'
-
-    return 'high' if current_theme.include?('contrast')
-
-    'auto'
+    current_user&.setting_contrast || 'auto'
   end
 
   def respond_with_error(code)

app/helpers/theme_helper.rb

@@ -18,9 +18,6 @@ module ThemeHelper
   end
 
   def theme_style_tags(theme)
-    # TODO: get rid of that when we retire the themes and perform the settings migration
-    theme = 'default' if %w(mastodon-light contrast system).include?(theme)
-
     vite_stylesheet_tag "themes/#{theme}", type: :virtual, media: 'all', crossorigin: 'anonymous'
   end
 

app/javascript/styles/contrast.scss

@@ -1 +0,0 @@
-@use 'common';

app/javascript/styles/mastodon-light.scss

@@ -1 +0,0 @@
-@use 'common';

app/lib/themes.rb

@@ -16,6 +16,6 @@ class Themes
   end
 
   def names
-    ['system'] + @conf.keys
+    @conf.keys
   end
 end

app/views/layouts/embedded.html.haml

@@ -15,7 +15,7 @@
     = vite_client_tag
     = vite_react_refresh_tag
     = vite_polyfills_tag
-    = theme_style_tags 'system'
+    = theme_style_tags 'default'
     = vite_preload_file_tag "mastodon/locales/#{I18n.locale}.json"
     = render_initial_state
     = vite_typescript_tag 'embed.tsx', integrity: true, crossorigin: 'anonymous'

app/views/settings/preferences/appearance/show.html.haml

@@ -23,33 +23,34 @@
 
   .fields-group
     = f.simple_fields_for :settings, current_user.settings do |ff|
-      = ff.input :theme,
-                 collection: Themes.instance.names,
-                 hint: false,
-                 include_blank: false,
-                 label_method: ->(theme) { I18n.t("themes.#{theme}", default: theme) },
-                 label: I18n.t('simple_form.labels.defaults.setting_theme'),
-                 wrapper: :with_label,
-                 required: false
-      - if Mastodon::Feature.new_theme_options_enabled?
-        .input.horizontal-options
-          = ff.input :'web.color_scheme',
-                     as: :radio_buttons,
-                     collection: %w(auto light dark),
-                     include_blank: false,
-                     label: I18n.t('simple_form.labels.defaults.setting_color_scheme'),
-                     label_method: ->(contrast) { I18n.t("color_scheme.#{contrast}", default: contrast) },
-                     wrapper: :with_label,
-                     required: false
-        .input.horizontal-options
-          = ff.input :'web.contrast',
-                     as: :radio_buttons,
-                     collection: %w(auto high),
-                     include_blank: false,
-                     label: I18n.t('simple_form.labels.defaults.setting_contrast'),
-                     label_method: ->(contrast) { I18n.t("contrast.#{contrast}", default: contrast) },
-                     wrapper: :with_label,
-                     required: false
+      - if Themes.instance.names.size > 1
+        = ff.input :theme,
+                   collection: Themes.instance.names,
+                   hint: false,
+                   include_blank: false,
+                   label_method: ->(theme) { I18n.t("themes.#{theme}", default: theme) },
+                   label: I18n.t('simple_form.labels.defaults.setting_theme'),
+                   wrapper: :with_label,
+                   required: false
+
+      .input.horizontal-options
+        = ff.input :'web.color_scheme',
+                   as: :radio_buttons,
+                   collection: %w(auto light dark),
+                   include_blank: false,
+                   label: I18n.t('simple_form.labels.defaults.setting_color_scheme'),
+                   label_method: ->(contrast) { I18n.t("color_scheme.#{contrast}", default: contrast) },
+                   wrapper: :with_label,
+                   required: false
+      .input.horizontal-options
+        = ff.input :'web.contrast',
+                   as: :radio_buttons,
+                   collection: %w(auto high),
+                   include_blank: false,
+                   label: I18n.t('simple_form.labels.defaults.setting_contrast'),
+                   label_method: ->(contrast) { I18n.t("contrast.#{contrast}", default: contrast) },
+                   wrapper: :with_label,
+                   required: false
 
   .fields-group
     = f.simple_fields_for :settings, current_user.settings do |ff|

config/locales/en.yml

@@ -2022,10 +2022,7 @@ en:
     review_link: Review terms of service
     title: The terms of service of %{domain} are changing
   themes:
-    contrast: Mastodon (High contrast)
-    default: Mastodon (Dark)
-    mastodon-light: Mastodon (Light)
-    system: Automatic (use system theme)
+    default: Mastodon
   time:
     formats:
       default: "%b %d, %Y, %H:%M"

config/settings.yml

@@ -19,7 +19,7 @@ defaults: &defaults
   show_staff_badge: true
   preview_sensitive_media: false
   noindex: false
-  theme: 'system'
+  theme: 'default'
   trends: true
   trendable_by_default: false
   disallowed_hashtags: # space separated string or list of hashtags without the hash

config/themes.yml

@@ -1,3 +1 @@
 default: styles/application.scss
-contrast: styles/contrast.scss
-mastodon-light: styles/mastodon-light.scss

db/migrate/20260209142402_migrate_default_theme_setting.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+class MigrateDefaultThemeSetting < ActiveRecord::Migration[8.0]
+  class Setting < ApplicationRecord; end
+
+  def up
+    Setting.reset_column_information
+
+    setting = Setting.find_by(var: 'theme')
+    return unless setting.present? && setting.attributes['value'].present? && %w(mastodon-light contrast system).include?(setting.attributes['value'])
+
+    Setting.upsert(
+      {
+        var: 'theme',
+        value: "--- default\n",
+      },
+      unique_by: index_exists?(:settings, [:thing_type, :thing_id, :var]) ? [:thing_type, :thing_id, :var] : :var
+    )
+  end
+
+  def down; end
+end

db/migrate/20260209143308_migrate_user_theme.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+class MigrateUserTheme < ActiveRecord::Migration[8.0]
+  disable_ddl_transaction!
+
+  # Dummy classes, to make migration possible across version changes
+  class User < ApplicationRecord; end
+
+  def up
+    User.where.not(settings: nil).find_each do |user|
+      settings = Oj.load(user.attributes_before_type_cast['settings'])
+      next if settings.nil? || settings['theme'].blank? || %w(system default mastodon-light contrast).exclude?(settings['theme'])
+
+      case settings['theme']
+      when 'default'
+        settings['web.color_scheme'] = 'dark'
+        settings['web.contrast'] = 'auto'
+      when 'contrast'
+        settings['web.color_scheme'] = 'dark'
+        settings['web.contrast'] = 'high'
+      when 'mastodon-light'
+        settings['web.color_scheme'] = 'light'
+        settings['web.contrast'] = 'auto'
+      end
+
+      settings['theme'] = 'default'
+
+      user.update_column('settings', Oj.dump(settings))
+    end
+  end
+end

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_01_27_141820) do
+ActiveRecord::Schema[8.0].define(version: 2026_02_09_143308) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_catalog.plpgsql"
 
@@ -1127,6 +1127,7 @@ ActiveRecord::Schema[8.0].define(version: 2026_01_27_141820) do
     t.string "poll_options", array: true
     t.boolean "sensitive"
     t.bigint "quote_id"
+    t.string "content_type"
     t.index ["account_id"], name: "index_status_edits_on_account_id"
     t.index ["status_id"], name: "index_status_edits_on_status_id"
   end
@@ -1189,6 +1190,8 @@ ActiveRecord::Schema[8.0].define(version: 2026_01_27_141820) do
     t.bigint "ordered_media_attachment_ids", array: true
     t.datetime "fetched_replies_at"
     t.integer "quote_approval_policy", default: 0, null: false
+    t.boolean "local_only"
+    t.string "content_type"
     t.index ["account_id", "id", "visibility", "updated_at"], name: "index_statuses_20190820", order: { id: :desc }, where: "(deleted_at IS NULL)"
     t.index ["account_id"], name: "index_statuses_on_account_id"
     t.index ["conversation_id"], name: "index_statuses_on_conversation_id"

spec/controllers/application_controller_spec.rb

@@ -97,24 +97,6 @@ RSpec.describe ApplicationController do
 
       expect(controller.view_context.current_theme).to eq 'contrast'
     end
-
-    it 'returns instances\'s default theme when user didn\'t set theme' do
-      current_user = Fabricate(:user)
-      current_user.settings.update(theme: 'contrast', noindex: false)
-      current_user.save
-      sign_in current_user
-
-      expect(controller.view_context.current_theme).to eq 'contrast'
-    end
-
-    it 'returns user\'s theme when it is set' do
-      current_user = Fabricate(:user)
-      current_user.settings.update(theme: 'mastodon-light')
-      current_user.save
-      sign_in current_user
-
-      expect(controller.view_context.current_theme).to eq 'mastodon-light'
-    end
   end
 
   context 'with ActionController::RoutingError' do

spec/helpers/theme_helper_spec.rb

@@ -6,17 +6,6 @@ RSpec.describe ThemeHelper do
   describe 'theme_style_tags' do
     let(:result) { helper.theme_style_tags(theme) }
 
-    context 'when using "system" theme' do
-      let(:theme) { 'system' }
-
-      it 'returns the default theme' do
-        expect(html_links.first.attributes.symbolize_keys)
-          .to include(
-            href: have_attributes(value: match(/default/))
-          )
-      end
-    end
-
     context 'when using "default" theme' do
       let(:theme) { 'default' }
 
@@ -27,17 +16,6 @@ RSpec.describe ThemeHelper do
           )
       end
     end
-
-    context 'when using other theme' do
-      let(:theme) { 'contrast' }
-
-      it 'returns the theme stylesheet without color scheme information' do
-        expect(html_links.first.attributes.symbolize_keys)
-          .to include(
-            href: have_attributes(value: match(/default/))
-          )
-      end
-    end
   end
 
   describe 'theme_color_tags' do

spec/system/settings/preferences/appearance_spec.rb

@@ -13,15 +13,13 @@ RSpec.describe 'Settings preferences appearance page' do
     expect(page)
       .to have_private_cache_control
 
-    select 'contrast', from: theme_selection_field
     check confirm_reblog_field
     uncheck confirm_delete_field
 
     check advanced_layout_field
 
     expect { save_changes }
-      .to change { user.reload.settings.theme }.to('contrast')
-      .and change { user.reload.settings['web.reblog_modal'] }.to(true)
+      .to change { user.reload.settings['web.reblog_modal'] }.to(true)
       .and change { user.reload.settings['web.delete_modal'] }.to(false)
       .and(change { user.reload.settings['web.advanced_layout'] }.to(true))
     expect(page)