db/message: override missing content-type charset to utf-8

Strictly speaking it should be inferred to be us-ascii when missing, but
utf-8 is a safer (and compatible) choice.

1 files changed, 8 insertions, 7 deletions

diff --git a/alot/db/message.py b/alot/db/message.py
index 74139315..f22db54b 100644
--- a/alot/db/message.py
+++ b/alot/db/message.py
@@ -149,16 +149,17 @@ class _MimeTree:
 
     def _fixup_charset(self):
         """
-        If a text MIME part declares an invalid charset, replace it with UTF-8
+        If a text MIME part declares an invalid or no charset, replace it
+        with UTF-8.
         """
         charset = self._part.get_param('charset')
-        if charset is None:
-            return
+        if charset is not None:
+            try:
+                return codecs.lookup(charset)
+            except LookupError:
+                pass
 
-        try:
-            codecs.lookup(charset)
-        except LookupError:
-            self._part.set_param('charset', 'utf-8')
+        self._part.set_param('charset', 'utf-8')
 
     def render_str(self, alt_preference = None):
         if self.children is not None: