Fix notmuch_message_get_message_id to never return NULL.

With the recent improvements to the handling of message IDs we
"know" that a NULL message ID is impossible, (so we simply
abort if the impossible happens).

1 files changed, 4 insertions, 0 deletions

diff --git a/notmuch.h b/notmuch.h
index 57ff8c8f..f568bc0a 100644
--- a/notmuch.h
+++ b/notmuch.h
@@ -338,6 +338,10 @@ notmuch_results_destroy (notmuch_results_t *results);
  * modified by the caller and will only be valid for as long as the
  * message is valid, (which is until the query from which it derived
  * is destroyed).
+ *
+ * This function will not return NULL since Notmuch ensures that every
+ * message has a unique message ID, (Notmuch will generate an ID for a
+ * message if the original file does not contain one).
  */
 const char *
 notmuch_message_get_message_id (notmuch_message_t *message);