keep the slice.step field as NULL if no step expression is given
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 1674b97..eac42d3 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -146,6 +146,12 @@
self.assertEquals(to_tuple(ast_tree), o)
self._assert_order(ast_tree, (0, 0))
+ def test_slice(self):
+ slc = ast.parse("x[::]").body[0].value.slice
+ self.assertIsNone(slc.upper)
+ self.assertIsNone(slc.lower)
+ self.assertIsNone(slc.step)
+
def test_nodeclasses(self):
x = ast.BinOp(1, 2, 3, lineno=0)
self.assertEquals(x.left, 1)