Add helpers for first day of the week

app/helpers/preferences_helper.rb

@@ -43,18 +43,21 @@ module PreferencesHelper
     ]
   end
 
-  def default_first_day_of_week
-    Date::DAYNAMES[Gitlab::CurrentSettings.default_first_day_of_week]
-  end
-
   def first_day_of_week_choices
     [
-      ["System Default (#{default_first_day_of_week})", nil],
-      ['Sunday', 0],
-      ['Monday', 1]
+      [_('Sunday'), 0],
+      [_('Monday'), 1]
     ]
   end
 
+  def default_first_day_of_week
+    first_day_of_week_choices.rassoc(Gitlab::CurrentSettings.default_first_day_of_week).first
+  end
+
+  def first_day_of_week_choices_with_default
+    first_day_of_week_choices.unshift([_('System Default (%{default})') % { default: default_first_day_of_week }, nil])
+  end
+
   def user_application_theme
     @user_application_theme ||= Gitlab::Themes.for_user(current_user).css_class
   end

app/views/admin/application_settings/_localization.html.haml

@@ -4,8 +4,8 @@
   %fieldset
     .form-group
       = f.label :default_first_day_of_week, _('Default first day of the week'), class: 'label-bold'
-      = f.select :default_first_day_of_week, options_for_select({_('Sunday') => 0, _('Monday') => 1}, @application_setting.default_first_day_of_week), {}, class: 'form-control'
+      = f.select :default_first_day_of_week, first_day_of_week_choices, {}, class: 'form-control'
       .form-text.text-muted
-        Default first day of the week in calendars and date pickers.
+        = _('Default first day of the week in calendars and date pickers.')
 
-  = f.submit 'Save changes', class: "btn btn-success"
+  = f.submit _('Save changes'), class: "btn btn-success"

app/views/profiles/preferences/show.html.haml

@@ -66,17 +66,17 @@
 
   .col-lg-4.profile-settings-sidebar
     %h4.prepend-top-0
-      Localization
+      = _('Localization')
     %p
-      Customize language and region related settings.
+      = _('Customize language and region related settings.')
       = succeed '.' do
-        = link_to 'Learn more', help_page_path('user/profile/preferences', anchor: 'localization'), target: '_blank'
+        = link_to _('Learn more'), help_page_path('user/profile/preferences', anchor: 'localization'), target: '_blank'
   .col-lg-8
     .form-group
       = f.label :first_day_of_week, class: 'label-bold' do
-        First day of the week
-      = f.select :first_day_of_week, first_day_of_week_choices, {}, class: 'form-control'
+        = _('First day of the week')
+      = f.select :first_day_of_week, first_day_of_week_choices_with_default, {}, class: 'form-control'
       .form-text.text-muted
-        Choose on what day the week should start.
+        = _('Choose on what day the week should start.')
     .form-group
-      = f.submit 'Save changes', class: 'btn btn-success'
+      = f.submit _('Save changes'), class: 'btn btn-success'

doc/user/profile/preferences.md

@@ -97,5 +97,5 @@ This following setting allows you to customize calendar layouts.
 
 ### First day of the week
 
-You can choose between **Default**, **Sunday** and **Monday** for the first day of the week. If you select **Default**, the system-wide default setting will be used.
+You can choose between **System Default**, **Sunday** and **Monday** for the first day of the week. If you select **System Default**, the system-wide default setting will be used.
 This preference will be used for all calendar views and datepickers.