Cleared up some function names in unit tests.

tests/test_line.py

@@ -150,7 +150,7 @@ class TestLine(unittest.TestCase):
         self.assertFalse(is_int(neg_a))
         self.assertFalse(is_int(plus))
 
-    def test_negated_addition_subtraction(self):
+    def test_negated_operator(self):
         neg = -N('+', L(1), L(2))
         self.assertEquals(generate_line(neg), '-(1 + 2)')
 
@@ -172,5 +172,6 @@ class TestLine(unittest.TestCase):
         plus = N('+', L(1), -L(4))
         self.assertEquals(generate_line(plus), '1 - 4')
 
+    def test_double_negation(self):
         neg = --L(1)
         self.assertEquals(generate_line(neg), '--1')