Closes #7334: close source files on ElementTree.parse and iterparse (partial backport of issue #10093 from 3.2).

Lib/xml/etree/ElementTree.py

@@ -642,8 +642,11 @@ class ElementTree(object):
     # @exception ParseError If the parser fails to parse the document.
 
     def parse(self, source, parser=None):
+        close_source = False
         if not hasattr(source, "read"):
             source = open(source, "rb")
+            close_source = True
+        try:
             if not parser:
                 parser = XMLParser(target=TreeBuilder())
             while 1:
@@ -653,6 +656,9 @@ class ElementTree(object):
                 parser.feed(data)
             self._root = parser.close()
             return self._root
+        finally:
+            if close_source:
+                source.close()
 
     ##
     # Creates a tree iterator for the root element.  The iterator loops
@@ -1189,16 +1195,19 @@ def parse(source, parser=None):
 # @return A (event, elem) iterator.
 
 def iterparse(source, events=None, parser=None):
+    close_source = False
     if not hasattr(source, "read"):
         source = open(source, "rb")
+        close_source = True
     if not parser:
         parser = XMLParser(target=TreeBuilder())
-    return _IterParseIterator(source, events, parser)
+    return _IterParseIterator(source, events, parser, close_source)
 
 class _IterParseIterator(object):
 
-    def __init__(self, source, events, parser):
+    def __init__(self, source, events, parser, close_source=False):
         self._file = source
+        self._close_file = close_source
         self._events = []
         self._index = 0
         self.root = self._root = None
@@ -1249,6 +1258,8 @@ class _IterParseIterator(object):
             except IndexError:
                 if self._parser is None:
                     self.root = self._root
+                    if self._close_file:
+                        self._file.close()
                     raise StopIteration
                 # load event buffer
                 del self._events[:]

Misc/NEWS

@@ -71,6 +71,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #7334: close source files on ElementTree.parse and iterparse.
+
 - Issue #13232: logging: Improved logging of exceptions in the presence of
   multiple encodings.
 

Modules/_elementtree.c

@@ -2915,8 +2915,11 @@ init_elementtree(void)
 
         "class ElementTree(ET.ElementTree):\n" /* public */
         "  def parse(self, source, parser=None):\n"
+        "    close_source = False\n"
         "    if not hasattr(source, 'read'):\n"
         "      source = open(source, 'rb')\n"
+        "      close_source = False\n"
+        "    try:\n"
         "      if parser is not None:\n"
         "        while 1:\n"
         "          data = source.read(65536)\n"
@@ -2928,6 +2931,9 @@ init_elementtree(void)
         "        parser = cElementTree.XMLParser()\n"
         "        self._root = parser._parse(source)\n"
         "      return self._root\n"
+        "    finally:\n"
+        "      if close_source:\n"
+        "        source.close()\n"
         "cElementTree.ElementTree = ElementTree\n"
 
         "def iter(node, tag=None):\n" /* helper */
@@ -2957,8 +2963,10 @@ init_elementtree(void)
         "class iterparse(object):\n"
         " root = None\n"
         " def __init__(self, file, events=None):\n"
+        "  self._close_file = False\n"
         "  if not hasattr(file, 'read'):\n"
         "    file = open(file, 'rb')\n"
+        "    self._close_file = True\n"
         "  self._file = file\n"
         "  self._events = []\n"
         "  self._index = 0\n"
@@ -2973,6 +2981,8 @@ init_elementtree(void)
         "    except IndexError:\n"
         "      if self._parser is None:\n"
         "        self.root = self._root\n"
+        "        if self._close_file:\n"
+        "          self._file.close()\n"
         "        raise StopIteration\n"
         "      # load event buffer\n"
         "      del self._events[:]\n"