python: fix get_property error when property doesn't exist

In Python bindings, Message.get_property fails with an AttributeError when trying to fetch a property that doesn't exist.

From d712832ba982085975c27b23bb502af82e638b39 Mon Sep 17 00:00:00 2001
From: hydrargyrum <dev@indigo.re>
Date: Sun, 6 Jan 2019 16:08:55 +0100
Subject: [PATCH] python: fix get_property error when property doesn't exist

diff --git a/bindings/python/notmuch/message.py b/bindings/python/notmuch/message.py
index de0fb4151e52e50c3f3eb684932b65820d74cf82..6e32b5f7ada2d825d4cd6c23403f6b6b1271691f 100644 (file)
--- a/bindings/python/notmuch/message.py
+++ b/bindings/python/notmuch/message.py
@@ -482,7 +482,9 @@ class Message(Python3StringMixIn):
         if status != 0:
             raise NotmuchError(status)
 
-        return value.value.decode('utf-8') if value is not None else None
+        if value is None or value.value is None:
+            return None
+        return value.value.decode('utf-8')
 
     def get_properties(self, prop="", exact=False):
         """ Get the properties of the message, returning a generator of