diff --git a/tests/test_Equation.py b/tests/test_Equation.py
index 55b8fc0..fd20bbe 100755
--- a/tests/test_Equation.py
+++ b/tests/test_Equation.py
@@ -75,6 +75,9 @@ def testRepr(self):
 
     def testStr(self):
         self.assertEqual(str(self.fn),"")
+        
+    def testCall(self):
+        self.assertEqual(self.fn(), 0)
 
     def tearDown(self):
         pass