From: W. Trevor King <wking@tremily.us>
Date: Fri, 7 Nov 2014 08:12:58 +0000 (-0800)
Subject: ssoma-mda: Fix RFC-2047 decoding for partially-encoded strings
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=0975a37a18d69e73149c860a8ad6da471787a60a;p=ssoma-mda.git

ssoma-mda: Fix RFC-2047 decoding for partially-encoded strings

Avoid:

  TypeError: sequence item 0: expected str instance, bytes found

When an RFC-2047-encoded string contains both an unencoded and an
encoded section.  For example:

  >>> import email.header
  >>> email.header.decode_header('Keld =?ISO-8859-1?Q?J=F8rn_Simonsen?=')
  [(b'Keld ', None), (b'J\xf8rn Simonsen', 'iso-8859-1')]

returns the decoded string in bytes but no charset information for the
first chunk.  I'm not sure what the default charset for header values
is, but RFC 2047 sets itself up to deal with non-ASCII header values
[1], so I'm guessing it's ASCII ;).

[1]: http://tools.ietf.org/html/rfc2047#section-1
---

diff --git a/ssoma-mda b/ssoma-mda
index d3b5406..abbe7bc 100755
--- a/ssoma-mda
+++ b/ssoma-mda
@@ -227,9 +227,13 @@ def _decode_header(string):
     'hello'
     >>> _decode_header(string='=?ISO-8859-1?Q?Keld_J=F8rn_Simonsen?=')
     'Keld Jørn Simonsen'
+    >>> _decode_header(string='Keld =?ISO-8859-1?Q?J=F8rn_Simonsen?=')
+    'Keld Jørn Simonsen'
     """
     chunks = []
     for decoded, charset in _email_header.decode_header(string):
+        if isinstance(decoded, bytes) and not charset:
+            charset = 'ASCII'
         if charset:
             decoded = str(decoded, charset)
         chunks.append(decoded)