Fix issue #1822: MIMEMultipart.is_multipart() behaves correctly for a
just-created (and empty) instance. Added tests for this. Thanks
Jonathan Share.
diff --git a/Lib/email/mime/multipart.py b/Lib/email/mime/multipart.py
index 5c8c9db..9661865 100644
--- a/Lib/email/mime/multipart.py
+++ b/Lib/email/mime/multipart.py
@@ -34,6 +34,12 @@
keyword arguments (or passed into the _params argument).
"""
MIMEBase.__init__(self, 'multipart', _subtype, **_params)
+
+ # Initialise _payload to an empty list as the Message superclass's
+ # implementation of is_multipart assumes that _payload is a list for
+ # multipart messages.
+ self._payload = []
+
if _subparts:
for p in _subparts:
self.attach(p)