#11767: use context manager to close file in __getitem__ to prevent FD leak

All of the other methods in mailbox that create message objects take care to
close the file descriptors they use, so it seems to make sense to have
__getitem__ do so as well.

Patch by Filip Gruszczyński.

1 files changed, 3 insertions, 1 deletions

diff --git a/Lib/mailbox.py b/Lib/mailbox.py
index 0e4f99bcaf..b96b270d68 100644
--- a/Lib/mailbox.py
+++ b/Lib/mailbox.py
@@ -20,6 +20,7 @@ import email
 import email.message
 import email.generator
 import io
+import contextlib
 try:
     if sys.platform == 'os2emx':
         # OS/2 EMX fcntl() not adequate
@@ -76,7 +77,8 @@ class Mailbox:
         if not self._factory:
             return self.get_message(key)
         else:
-            return self._factory(self.get_file(key))
+            with contextlib.closing(self.get_file(key)) as file:
+                return self._factory(file)
 
     def get_message(self, key):
         """Return a Message representation or raise a KeyError."""