multiple negative numbers and \n

String calculator

@@ -61,6 +61,17 @@ class TestStingCalculator(unittest.TestCase):
         with self.assertRaises(ValueError) as e:
             self.calculator.add("-1,2")
         self.assertEqual(str(e.exception), "negatives not allowed: -1")
+    def test_multiple_negative_numbers_exception(self):
+        with self.assertRaises(ValueError)as e:
+            self.calculator.add("-1,-2,3")
+        self.assertEqual(str(e.exception),"negatives not allowed: -1,-2")
+        with self.assertRaises(ValueError) as e:
+            self.calculator.add("-1,-3,4")
+        self.assertEqual(str(e.exception),"negatives not allowed: -1,-3")
+        with self.assertRaises(ValueError) as e:
+            self.calculator.add("-1\n-3,4")
+        self.assertEqual(str(e.exception),"negatives not allowed: -1,-3")
+        
 
 if __name__=='__main__':
     unittest.main()
\ No newline at end of file