__init__(): Fix an invariant, that the charset item in a chunk tuple
must be a Charset instance, not a string. The bug here was that
self._charset wasn't being converted to a Charset instance so later
.append() calls which used the default charset would break.
_split(): If the charset of the chunk is '8bit', return the chunk
unchanged. We can't safely split it, so this is the avenue of least
harm.
diff --git a/Lib/email/Header.py b/Lib/email/Header.py
index 378b3dd..9bbc32f 100644
--- a/Lib/email/Header.py
+++ b/Lib/email/Header.py
@@ -153,6 +153,8 @@
"""
if charset is None:
charset = USASCII
+ if not isinstance(charset, Charset):
+ charset = Charset(charset)
self._charset = charset
self._continuation_ws = continuation_ws
cws_expanded_len = len(continuation_ws.replace('\t', SPACE8))
@@ -233,14 +235,21 @@
self._chunks.append((s, charset))
def _split(self, s, charset, firstline=False):
- # Split up a header safely for use with encode_chunks. BAW: this
- # appears to be a private convenience method.
+ # Split up a header safely for use with encode_chunks.
splittable = charset.to_splittable(s)
encoded = charset.from_splittable(splittable)
elen = charset.encoded_header_len(encoded)
if elen <= self._maxlinelen:
return [(encoded, charset)]
+ # If we have undetermined raw 8bit characters sitting in a byte
+ # string, we really don't know what the right thing to do is. We
+ # can't really split it because it might be multibyte data which we
+ # could break if we split it between pairs. The least harm seems to
+ # be to not split the header at all, but that means they could go out
+ # longer than maxlinelen.
+ elif charset == '8bit':
+ return [(s, charset)]
# BAW: I'm not sure what the right test here is. What we're trying to
# do is be faithful to RFC 2822's recommendation that ($2.2.3):
#