[Python-checkins] r62092 - in sandbox/trunk/2to3/lib2to3: pytree.py tests/test_pytree.py

Tue Apr 1 18:27:10 CEST 2008

Author: collin.winter
Date: Tue Apr 1 18:27:10 2008
New Revision: 62092
Modified:
 sandbox/trunk/2to3/lib2to3/pytree.py
 sandbox/trunk/2to3/lib2to3/tests/test_pytree.py
Log:
Add get_prev_sibling() to complement pytree's get_next_sibling().
Modified: sandbox/trunk/2to3/lib2to3/pytree.py
==============================================================================

--- sandbox/trunk/2to3/lib2to3/pytree.py	(original)
+++ sandbox/trunk/2to3/lib2to3/pytree.py	Tue Apr 1 18:27:10 2008
@@ -167,13 +167,27 @@
 return None
 
 # Can't use index(); we need to test by identity
- for i, sibling in enumerate(self.parent.children):
- if sibling is self:
+ for i, child in enumerate(self.parent.children):
+ if child is self:
 try:
 return self.parent.children[i+1]
 except IndexError:
 return None
 
+ def get_prev_sibling(self):
+ """Return the node immediately preceding the invocant in their
+ parent's children list. If the invocant does not have a previous
+ sibling, return None."""
+ if self.parent is None:
+ return None
+
+ # Can't use index(); we need to test by identity
+ for i, child in enumerate(self.parent.children):
+ if child is self:
+ if i == 0:
+ return None
+ return self.parent.children[i-1]
+
 def get_suffix(self):
 """Return the string immediately following the invocant node. This
 is effectively equivalent to node.get_next_sibling().get_prefix()"""
Modified: sandbox/trunk/2to3/lib2to3/tests/test_pytree.py
==============================================================================
--- sandbox/trunk/2to3/lib2to3/tests/test_pytree.py	(original)
+++ sandbox/trunk/2to3/lib2to3/tests/test_pytree.py	Tue Apr 1 18:27:10 2008
@@ -319,6 +319,24 @@
 self.assertEqual(l2.get_next_sibling(), None)
 self.assertEqual(p1.get_next_sibling(), None)
 
+ def testNodePrevSibling(self):
+ n1 = pytree.Node(1000, [])
+ n2 = pytree.Node(1000, [])
+ p1 = pytree.Node(1000, [n1, n2])
+
+ self.failUnless(n2.get_prev_sibling() is n1)
+ self.assertEqual(n1.get_prev_sibling(), None)
+ self.assertEqual(p1.get_prev_sibling(), None)
+
+ def testLeafPrevSibling(self):
+ l1 = pytree.Leaf(100, "a")
+ l2 = pytree.Leaf(100, "b")
+ p1 = pytree.Node(1000, [l1, l2])
+
+ self.failUnless(l2.get_prev_sibling() is l1)
+ self.assertEqual(l1.get_prev_sibling(), None)
+ self.assertEqual(p1.get_prev_sibling(), None)
+
 
 class TestPatterns(support.TestCase):
 
