From 17173cfe7b5f880c02a8f9468f17607ec84e5b39 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kristj=C3=A1n=20Valur=20J=C3=B3nsson?=
 <kristjan@ccpgames.com>
Date: Wed, 9 Jun 2010 08:13:42 +0000
Subject: http://bugs.python.org/issue8832 Issue minidom.unlink with a context
 manager

---
 Doc/library/xml.dom.minidom.rst | 7 +++++++
 Lib/test/test_minidom.py        | 7 +++++++
 Lib/xml/dom/minidom.py          | 8 ++++++++
 3 files changed, 22 insertions(+)

diff --git a/Doc/library/xml.dom.minidom.rst b/Doc/library/xml.dom.minidom.rst
index 5ece1ca..792a8dc 100644
--- a/Doc/library/xml.dom.minidom.rst
+++ b/Doc/library/xml.dom.minidom.rst
@@ -114,6 +114,13 @@ module documentation.  This section lists the differences between the API and
    to be called on the :class:`Document` object, but may be called on child nodes
    to discard children of that node.
 
+   You can avoid calling this method explicitly by using the :keyword:`with`
+   statement. The following code will automatically unlink *dom* when the
+   :keyword:`with` block is exited::
+
+      with xml.dom.minidom.parse(datasource) as dom:
+          ... # Work with dom.
+
 
 .. method:: Node.writexml(writer, indent="", addindent="", newl="", encoding="")
 
diff --git a/Lib/test/test_minidom.py b/Lib/test/test_minidom.py
index 32863bf..9a9acfb 100644
--- a/Lib/test/test_minidom.py
+++ b/Lib/test/test_minidom.py
@@ -228,7 +228,14 @@ class MinidomTest(unittest.TestCase):
 
     def testUnlink(self):
         dom = parse(tstfile)
+        self.assertTrue(dom.childNodes)
         dom.unlink()
+        self.assertFalse(dom.childNodes)
+
+    def testContext(self):
+        with parse(tstfile) as dom:
+            self.assertTrue(dom.childNodes)
+        self.assertFalse(dom.childNodes)
 
     def testElement(self):
         dom = Document()
diff --git a/Lib/xml/dom/minidom.py b/Lib/xml/dom/minidom.py
index f4f4400..7616b46 100644
--- a/Lib/xml/dom/minidom.py
+++ b/Lib/xml/dom/minidom.py
@@ -268,6 +268,14 @@ class Node(xml.dom.Node):
         self.previousSibling = None
         self.nextSibling = None
 
+    # A Node is its own context manager, to ensure that an unlink() call occurs.
+    # This is similar to how a file object works.
+    def __enter__(self):
+        return self
+
+    def __exit__(self, et, ev, tb):
+        self.unlink()
+
 defproperty(Node, "firstChild", doc="First child node, or None.")
 defproperty(Node, "lastChild",  doc="Last child node, or None.")
 defproperty(Node, "localName",  doc="Namespace-local name of this node.")
-- 
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