Fixes for SF #1076485, which I'll apply to the CVS head too. The problem was

caused by a self._input.readline() call that wasn't checking for the
NeedsMoreData marker.

msg_43.txt contains a message that illustrates the problem, when
email.message_from_*() is called.  That interface uses the Parser API, which
splits reads into 8192 byte chunks.  It so happens that for the test message,
the 8192 chunk falls inside a message/delivery-status, which is where in the
FeedParser the readline() call was that didn't check for NeedsMoreData.

I also added an assert to unreadline() so it'll be more evident if an attempt
to push back NeedsMoreData ever happens again.

Bump the email package version number.

1 files changed, 13 insertions, 2 deletions

diff --git a/Lib/email/FeedParser.py b/Lib/email/FeedParser.py
index f514728..5aad15d 100644
--- a/Lib/email/FeedParser.py
+++ b/Lib/email/FeedParser.py
@@ -87,6 +87,7 @@ class BufferedSubFile(object):
 
     def unreadline(self, line):
         # Let the consumer push a line back into the buffer.
+        assert line is not NeedMoreData
         self._lines.append(line)
 
     def push(self, data):
@@ -242,8 +243,18 @@ class FeedParser:
                 # EOF.  We want to see if we're at the end of this subpart, so
                 # first consume the blank line, then test the next line to see
                 # if we're at this subpart's EOF.
-                line = self._input.readline()
-                line = self._input.readline()
+                while True:
+                    line = self._input.readline()
+                    if line is NeedMoreData:
+                        yield NeedMoreData
+                        continue
+                    break
+                while True:
+                    line = self._input.readline()
+                    if line is NeedMoreData:
+                        yield NeedMoreData
+                        continue
+                    break
                 if line == '':
                     break
                 # Not at EOF so this is a line we're going to need.