Enable advanced user search regardless of namespace

ee/app/services/concerns/search/elasticsearchable.rb

@@ -3,6 +3,7 @@
 module Search
   module Elasticsearchable
     SCOPES_ONLY_BASIC_SEARCH = %w(epics).freeze
+    SCOPES_ADVANCED_SEARCH_ALWAYS_ENABLED = %w[users].freeze
     def use_elasticsearch?
       return false if params[:basic_search]
@@ -16,6 +17,10 @@ def elasticsearchable_scope
       raise NotImplementedError
     end
+    def global_elasticsearchable_scope?
+      SCOPES_ADVANCED_SEARCH_ALWAYS_ENABLED.include?(params[:scope])
+    end
+
     def advanced_user_search?
       return true unless params[:scope] == 'users'
       return false unless ::Feature.enabled?(:advanced_user_search, current_user, type: :ops)

ee/app/services/ee/search/group_service.rb

@@ -8,7 +8,7 @@ module GroupService
       override :elasticsearchable_scope
       def elasticsearchable_scope
-        group
+        group unless global_elasticsearchable_scope?
       end
       override :zoekt_searchable_scope

ee/app/services/ee/search/project_service.rb

@@ -57,7 +57,7 @@ def use_default_branch?
       override :elasticsearchable_scope
       def elasticsearchable_scope
-        project
+        project unless global_elasticsearchable_scope?
       end
       override :zoekt_searchable_scope

ee/spec/services/concerns/search/elasticsearchable_spec.rb

@@ -71,6 +71,20 @@ def elasticsearchable_scope
     end
   end
+  describe '#global_elasticsearchable_scope?' do
+    it 'is false' do
+      expect(class_instance).not_to be_global_elasticsearchable_scope
+    end
+
+    context 'when scope is users' do
+      let(:params) { { scope: 'users' } }
+
+      it 'is true' do
+        expect(class_instance).to be_global_elasticsearchable_scope
+      end
+    end
+  end
+
   describe "#advanced_user_search?" do
     it 'is true when the scope is not users' do
       expect(class_instance).to be_advanced_user_search

ee/spec/services/search/group_service_spec.rb

@@ -62,6 +62,23 @@
     end
   end
+  describe '#elasticsearchable_scope' do
+    let(:service) { described_class.new(user, group, scope: scope) }
+    let(:scope) { 'blobs' }
+
+    it 'is set to group' do
+      expect(service.elasticsearchable_scope).to eq(group)
+    end
+
+    context 'when the scope is users' do
+      let(:scope) { 'users' }
+
+      it 'is nil' do
+        expect(service.elasticsearchable_scope).to be_nil
+      end
+    end
+  end
+
   context 'when searching with Zoekt' do
     let(:service) { described_class.new(user, group, search: 'foobar', scope: scope, basic_search: basic_search, page: page) }
     let(:use_zoekt) { true }

ee/spec/services/search/project_service_spec.rb

@@ -43,6 +43,25 @@
     end
   end
+  describe '#elasticsearchable_scope' do
+    let(:service) { described_class.new(user, project, scope: scope) }
+    let(:scope) { 'blobs' }
+    let_it_be(:user) { create(:user) }
+    let_it_be(:project) { create(:project) }
+
+    it 'is set to project' do
+      expect(service.elasticsearchable_scope).to eq(project)
+    end
+
+    context 'when the scope is users' do
+      let(:scope) { 'users' }
+
+      it 'is nil' do
+        expect(service.elasticsearchable_scope).to be_nil
+      end
+    end
+  end
+
   context 'when searching with Zoekt' do
     let_it_be(:user) { create(:user) }
     let_it_be(:project) { create(:project, namespace: user.namespace) }