Fix bug with threading when cover ref is missing

When the cover letter is missing and we're starting in the middle of the
thread, do not discard messages in the mbox that come before the msgid
that we want.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>

1 files changed, 11 insertions, 2 deletions

diff --git a/b4/__init__.py b/b4/__init__.py
index cee14f8..79a0c2e 100644
--- a/b4/__init__.py
+++ b/b4/__init__.py
@@ -1928,8 +1928,12 @@ def save_strict_thread(in_mbx, out_mbx, msgid):
             logger.debug('Looking at: %s', c_msgid)
 
             refs = set()
-            for ref in msg.get('References', msg.get('In-Reply-To', '')).split():
-                ref = ref.strip().strip('<>')
+            msgrefs = list()
+            if msg.get('In-Reply-To', None):
+                msgrefs += email.utils.getaddresses([str(x) for x in msg.get_all('in-reply-to', [])])
+            if msg.get('References', None):
+                msgrefs += email.utils.getaddresses([str(x) for x in msg.get_all('references', [])])
+            for ref in set([x[1] for x in msgrefs]):
                 if ref in got or ref in want:
                     want.add(c_msgid)
                 elif len(ref):
@@ -1950,6 +1954,11 @@ def save_strict_thread(in_mbx, out_mbx, msgid):
                     # Add all these to want
                     want.update(maybe[c_msgid])
                     maybe.pop(c_msgid)
+                # Add all maybes that have the same ref into want
+                for ref in refs:
+                    if ref in maybe:
+                        want.update(maybe[ref])
+                        maybe.pop(ref)
 
         # Remove any entries not in "seen" (missing messages)
         for c_msgid in set(want):