Added closing context manager to files returned by open

fs/zipfs.py

@@ -8,6 +8,7 @@ A FS object that represents the contents of a Zip file
 
 import datetime
 import os.path
+from contextlib import closing
 
 from fs.base import *
 from fs.path import *
@@ -32,7 +33,6 @@ class ZipNotFoundError(CreateFailedError):
 
 
 class _TempWriteFile(object):
-
     """Proxies a file object and calls a callback when the file is closed."""
 
     def __init__(self, fs, filename, close_callback):
@@ -54,9 +54,14 @@ class _TempWriteFile(object):
     def flush(self):
         self._file.flush()
 
+    def __enter__(self):
+        return self
 
-class _ExceptionProxy(object):
+    def __exit__(self, type, value, traceback):
+        self.close()
 
+
+class _ExceptionProxy(object):
     """A placeholder for an object that may no longer be used."""
 
     def __getattr__(self, name):
@@ -70,7 +75,6 @@ class _ExceptionProxy(object):
 
 
 class ZipFS(FS):
-
     """A FileSystem that represents a zip file."""
 
     _meta = { 'thread_safe' : True,
@@ -177,7 +181,6 @@ class ZipFS(FS):
             return self.read_only
         return super(ZipFS, self).getmeta(meta_name, default)
 
-
     def close(self):
         """Finalizes the zip file so that it can be read.
         No further operations will work after this method is called."""
@@ -202,7 +205,7 @@ class ZipFS(FS):
                     contents = self.zf.read(self._encode_path(path))
             except KeyError:
                 raise ResourceNotFoundError(path)
-            return StringIO(contents)
+            return closing(StringIO(contents))
 
         if 'w' in mode:
             if self.zip_mode not in 'wa':
@@ -215,7 +218,6 @@ class ZipFS(FS):
 
             self._add_resource(path)
             f = _TempWriteFile(self.temp_fs, path, self._on_write_close)
-
             return f
 
         raise ValueError("Mode must contain be 'r' or 'w'")