diff --git a/test/browser_test_helper.rb b/test/browser_test_helper.rb
index 8f2a25918..e34d43f31 100644
--- a/test/browser_test_helper.rb
+++ b/test/browser_test_helper.rb
@@ -122,7 +122,7 @@ class TestCase < Test::Unit::TestCase
     end
   end
 
-  def screenshot(params)
+  def screenshot(params = {})
     instance = params[:browser] || @browser
     comment = params[:comment] || ''
     filename = "tmp/#{Time.zone.now.strftime('screenshot_%Y_%m_%d__%H_%M_%S_%L')}_#{comment}#{instance.hash}.png"