Introduce ClosingContextManager for classes that already implement close()

2 files changed, 10 insertions, 7 deletions

diff --git a/paramiko/sftp_file.py b/paramiko/sftp_file.py
index 03d67b33..e0fb2297 100644
--- a/paramiko/sftp_file.py
+++ b/paramiko/sftp_file.py
@@ -34,9 +34,10 @@ from paramiko.py3compat import long
 from paramiko.sftp import CMD_CLOSE, CMD_READ, CMD_DATA, SFTPError, CMD_WRITE, \
     CMD_STATUS, CMD_FSTAT, CMD_ATTRS, CMD_FSETSTAT, CMD_EXTENDED
 from paramiko.sftp_attr import SFTPAttributes
+from paramiko.util import ClosingContextManager
 
 
-class SFTPFile (BufferedFile):
+class SFTPFile (BufferedFile, ClosingContextManager):
     """
     Proxy object for a file on the remote server, in client mode SFTP.
 
@@ -488,9 +489,3 @@ class SFTPFile (BufferedFile):
             x = self._saved_exception
             self._saved_exception = None
             raise x
-            
-    def __enter__(self):
-        return self
-
-    def __exit__(self, type, value, traceback):
-        self.close()
diff --git a/paramiko/util.py b/paramiko/util.py
index f4ee3adc..ee1a3abb 100644
--- a/paramiko/util.py
+++ b/paramiko/util.py
@@ -320,3 +320,11 @@ def constant_time_bytes_eq(a, b):
     for i in (xrange if PY2 else range)(len(a)):
         res |= byte_ord(a[i]) ^ byte_ord(b[i])
     return res == 0
+
+
+class ClosingContextManager(object):
+    def __enter__(self):
+        return self
+
+    def __exit__(self, type, value, traceback):
+        self.close()