spec/features/admin/dashboard_spec.rb

@@ -4,7 +4,9 @@ RSpec.describe 'Admin dashboard', type: :feature do
   let(:user) { create :user }
 
   before do
-    allow(user).to receive(:is_admin?).and_return(true)
+    allow(Devise::LDAP::Adapter).to receive(:get_ldap_param)
+      .with(user.cn, :admin).and_return(["true"])
+
     login_as user, :scope => :user
   end