Allow admin to disable all restricted visibility levels

app/controllers/admin/application_settings_controller.rb

@@ -71,6 +71,8 @@ class Admin::ApplicationSettingsController < Admin::ApplicationController
     params[:application_setting][:disabled_oauth_sign_in_sources] =
       AuthHelper.button_based_providers.map(&:to_s) -
       Array(enabled_oauth_sign_in_sources)
+
+    params[:application_setting][:restricted_visibility_levels]&.delete("")
     params.delete(:domain_blacklist_raw) if params[:domain_blacklist_file]
 
     params.require(:application_setting).permit(

app/helpers/application_settings_helper.rb

@@ -34,17 +34,17 @@ module ApplicationSettingsHelper
 
   # Return a group of checkboxes that use Bootstrap's button plugin for a
   # toggle button effect.
-  def restricted_level_checkboxes(help_block_id)
+  def restricted_level_checkboxes(help_block_id, checkbox_name)
     Gitlab::VisibilityLevel.options.map do |name, level|
       checked = restricted_visibility_levels(true).include?(level)
       css_class = checked ? 'active' : ''
-      checkbox_name = "application_setting[restricted_visibility_levels][]"
+      tag_name = "application_setting_visibility_level_#{level}"
 
-      label_tag(name, class: css_class) do
+      label_tag(tag_name, class: css_class) do
         check_box_tag(checkbox_name, level, checked,
                       autocomplete: 'off',
                       'aria-describedby' => help_block_id,
-                      id: name) + visibility_level_icon(level) + name
+                      id: tag_name) + visibility_level_icon(level) + name
       end
     end
   end

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

@@ -22,7 +22,9 @@
     .form-group
       = f.label :restricted_visibility_levels, class: 'control-label col-sm-2'
       .col-sm-10
-        - restricted_level_checkboxes('restricted-visibility-help').each do |level|
+        - checkbox_name = 'application_setting[restricted_visibility_levels][]'
+        = hidden_field_tag(checkbox_name)
+        - restricted_level_checkboxes('restricted-visibility-help', checkbox_name).each do |level|
           .checkbox
             = level
         %span.help-block#restricted-visibility-help

changelogs/unreleased/32408-enable-disable-all-restricted-visibility-levels.yml

+---
+title: Allow admins to disable all restricted visibility levels
+merge_request: 12649
+author:

spec/features/admin/admin_settings_spec.rb

@@ -16,6 +16,19 @@ feature 'Admin updates settings', feature: true do
     expect(page).to have_content "Application settings saved successfully"
   end
 
+  scenario 'Uncheck all restricted visibility levels' do
+    find('#application_setting_visibility_level_0').set(false)
+    find('#application_setting_visibility_level_10').set(false)
+    find('#application_setting_visibility_level_20').set(false)
+
+    click_button 'Save'
+
+    expect(page).to have_content "Application settings saved successfully"
+    expect(find('#application_setting_visibility_level_0')).not_to be_checked
+    expect(find('#application_setting_visibility_level_10')).not_to be_checked
+    expect(find('#application_setting_visibility_level_20')).not_to be_checked
+  end
+
   scenario 'Change application settings' do
     uncheck 'Gravatar enabled'
     fill_in 'Home page URL', with: 'https://about.gitlab.com/'