Improved test cases for multiplication sign omission in line generator.

line.py

@@ -115,9 +115,17 @@ def generate_line(root):
                     # a * b -> ab
                     # a * 2 -> a * 2
                     # a * (b) -> a(b)
+                    # (a) * b -> (a)b
+                    # (a) * (b) -> (a)(b)
                     # 2 * a -> 2a
-                    if (is_id(left) and (is_id(right) or e[1][0] == '(')) \
-                            or (is_int(left) and is_id(right)):
+                    left_id = is_id(left)
+                    right_id = is_id(right)
+                    left_paren = e[0][-1] == ')'
+                    right_paren = e[1][0] == '('
+                    left_int = is_int(left)
+
+                    if (left_id or left_paren or left_int) \
+                            and (right_id or right_paren):
                         sep = ''
 
                 result += sep.join(e)

tests/test_line.py

@@ -18,7 +18,7 @@ class TestLine(unittest.TestCase):
         l0, l1 = L(1), L(2)
         plus = N('+', l0, l1)
         times = N('*', plus, plus)
-        self.assertEquals(generate_line(times), '(1 + 2) * (1 + 2)')
+        self.assertEquals(generate_line(times), '(1 + 2)(1 + 2)')
 
     def test_parentheses_equal_precedence_right(self):
         l0, l1, l2 = L(1), L(2), L(3)
@@ -107,6 +107,12 @@ class TestLine(unittest.TestCase):
         mul = N('*', a, N('-', b, c))
         self.assertEquals(generate_line(mul), 'a(b - c)')
 
+        mul = N('*', N('+', a, b), c)
+        self.assertEquals(generate_line(mul), '(a + b)c')
+
+        mul = N('*', N('+', a, b), N('+', c, l2))
+        self.assertEquals(generate_line(mul), '(a + b)(c + 2)')
+
         mul = N('*', l2, a)
         self.assertEquals(generate_line(mul), '2a')