From 232910aaea8b6719f40e42924afa11515d8cd1fe Mon Sep 17 00:00:00 2001
From: Joni Orponen <joni.orponen@gmail.com>
Date: Sat, 11 May 2019 16:54:20 +0200
Subject: [PATCH] Use a better type check in the payload parser.

---
 news/7.bugfix          | 2 ++
 plone/rfc822/_utils.py | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)
 create mode 100644 news/7.bugfix

diff --git a/news/7.bugfix b/news/7.bugfix
new file mode 100644
index 0000000..0479f09
--- /dev/null
+++ b/news/7.bugfix
@@ -0,0 +1,2 @@
+- Use a better type check in the payload parser.
+  [Rotonen]
diff --git a/plone/rfc822/_utils.py b/plone/rfc822/_utils.py
index 403c8b4..8bcd098 100644
--- a/plone/rfc822/_utils.py
+++ b/plone/rfc822/_utils.py
@@ -246,7 +246,7 @@ def initializeObject(context, fields, message, defaultCharset="utf-8"):
         return
 
     # A single payload is a string, multiparts are lists
-    if isinstance(payloads, str):
+    if isinstance(payloads, six.string_types):
         if len(primary) != 1:
             raise ValueError(
                 "Got a single string payload for message, but no primary "