lib: Add the exclude flag to notmuch_query_search_threads

Add the NOTMUCH_MESSAGE_FLAG_EXCLUDED flag to
notmuch_query_search_threads. Implemented by inspecting the tags
directly in _notmuch_thread_create/_thread_add_message rather than as
a Xapian query for speed reasons.

Note notmuch_thread_get_matched_messages now returns the number of
non-excluded matching messages. This API is not totally desirable but
fixing it means breaking binary compatibility so we delay that.

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/notmuch.h b/lib/notmuch.h
index f75afaeb..babd2086 100644
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -672,8 +672,10 @@ notmuch_thread_get_toplevel_messages (notmuch_thread_t *thread);
 /* Get the number of messages in 'thread' that matched the search.
  *
  * This count includes only the messages in this thread that were
- * matched by the search from which the thread was created. Contrast
- * with notmuch_thread_get_total_messages() .
+ * matched by the search from which the thread was created and were
+ * not excluded by any exclude tags passed in with the query (see
+ * notmuch_query_add_tag_exclude). Contrast with
+ * notmuch_thread_get_total_messages() .
  */
 int
 notmuch_thread_get_matched_messages (notmuch_thread_t *thread);