diff --git a/spec/classes/config_spec.rb b/spec/classes/config_spec.rb
index caa070e..a79a444 100644
--- a/spec/classes/config_spec.rb
+++ b/spec/classes/config_spec.rb
@@ -189,6 +189,12 @@ describe 'nginx::config' do
             '  log_format format2 \'FORMAT2\';',
           ],
         },
+        {
+          :title    => 'should not set log formats',
+          :attr     => 'log_format',
+          :value    => {},
+          :notmatch => /log_format/,
+        },
         {
           :title => 'should set access_log',
           :attr  => 'http_access_log',