[Python-checkins] r54810 - in sandbox/trunk/2to3: pytree.py tests/test_pytree.py

[collin.winter]

Author: collin.winter
Date: Sat Apr 14 00:03:36 2007
New Revision: 54810

Modified:
   sandbox/trunk/2to3/pytree.py
   sandbox/trunk/2to3/tests/test_pytree.py
Log:
Add a get_next_sibling() method to pytree.Base.

Modified: sandbox/trunk/2to3/pytree.py
==============================================================================
--- sandbox/trunk/2to3/pytree.py	(original)
+++ sandbox/trunk/2to3/pytree.py	Sat Apr 14 00:03:36 2007
@@ -142,6 +142,21 @@
                     del self.parent.children[i]
                     self.parent = None
                     return i
+                    
+    def get_next_sibling(self):
+        """Return the node immediately following the invocant in their
+        parent's children list. If the invocant does not have a next
+        sibling, return None."""
+        if self.parent is None:
+            return None
+        
+        # Can't use index(); we need to test by identity
+        for i, sibling in enumerate(self.parent.children):
+            if sibling is self:
+                try:
+                    return self.parent.children[i+1]
+                except IndexError:
+                    return None
 
 
 class Node(Base):

Modified: sandbox/trunk/2to3/tests/test_pytree.py
==============================================================================
--- sandbox/trunk/2to3/tests/test_pytree.py	(original)
+++ sandbox/trunk/2to3/tests/test_pytree.py	Sat Apr 14 00:03:36 2007
@@ -262,6 +262,24 @@
         
         # I don't care what it raises, so long as it's an exception
         self.assertRaises(Exception, n1.append_child, list)
+        
+    def testNodeNextSibling(self):
+        n1 = pytree.Node(1000, [])
+        n2 = pytree.Node(1000, [])
+        p1 = pytree.Node(1000, [n1, n2])
+        
+        self.failUnless(n1.get_next_sibling() is n2)
+        self.assertEqual(n2.get_next_sibling(), None)
+        self.assertEqual(p1.get_next_sibling(), None)
+        
+    def testLeafNextSibling(self):
+        l1 = pytree.Leaf(100, "a")
+        l2 = pytree.Leaf(100, "b")
+        p1 = pytree.Node(1000, [l1, l2])
+        
+        self.failUnless(l1.get_next_sibling() is l2)
+        self.assertEqual(l2.get_next_sibling(), None)
+        self.assertEqual(p1.get_next_sibling(), None)
 
 
 class TestPatterns(support.TestCase):