From 3474263823d41b2a92942c5f66a87062757f1928 Mon Sep 17 00:00:00 2001
From: Carl Worth <cworth@cworth.org>
Date: Wed, 24 Feb 2010 17:02:31 -0800
Subject: [PATCH] emacs: Avoid removing the unread tag due to internal
 navigation

Sometimes the internals of the implementation navigate among messages,
(as opposed to the user explicitly requesting the next message to be
shown). In these cases we don't want to remove the unread tag from the
message navigated to.

This fixes a bug where invocation of notmuch-show-next-unread-message
would clear the unread tag from all messages in a thread.
---
 notmuch.el | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/notmuch.el b/notmuch.el
index 341ac809..7723730f 100644
--- a/notmuch.el
+++ b/notmuch.el
@@ -503,14 +503,13 @@ by searching backward)."
       (setq btn (previous-button (button-start btn))))
     (not (invisible-p (button-get btn 'invisibility-spec)))))
 
-(defun notmuch-show-next-message ()
+(defun notmuch-show-next-message-without-marking-read ()
   "Advance to the beginning of the next message in the buffer.
 
 Moves to the last visible character of the current message if
 already on the last message in the buffer.
 
 Returns nil if already on the last message in the buffer."
-  (interactive)
   (notmuch-show-move-to-current-message-summary-line)
   (if (re-search-forward notmuch-show-message-begin-regexp nil t)
       (progn
@@ -521,7 +520,18 @@ Returns nil if already on the last message in the buffer."
     (while (point-invisible-p)
       (backward-char))
     (recenter 0)
-    nil)
+    nil))
+
+(defun notmuch-show-next-message ()
+  "Advance to the beginning of the next message in the buffer.
+and remove the unread tag from that message.
+
+Moves to the last visible character of the current message if
+already on the last message in the buffer.
+
+Returns nil if already on the last message in the buffer."
+  (interactive)
+  (notmuch-show-next-message-without-marking-read)
   (notmuch-show-mark-read))
 
 (defun notmuch-show-find-next-message ()
@@ -534,7 +544,7 @@ message if already within the last message in the buffer."
   ; Looks like we have to use both.
   (save-excursion
     (save-window-excursion
-      (notmuch-show-next-message)
+      (notmuch-show-next-message-without-marking-read)
       (point))))
 
 (defun notmuch-show-next-unread-message ()
@@ -542,17 +552,19 @@ message if already within the last message in the buffer."
 
 Moves to the last visible character of the current message if
 there are no more unread messages past the current point."
-  (notmuch-show-next-message)
+  (notmuch-show-next-message-without-marking-read)
   (while (and (not (notmuch-show-last-message-p))
 	      (not (notmuch-show-message-unread-p)))
-    (notmuch-show-next-message))
+    (notmuch-show-next-message-without-marking-read))
   (if (not (notmuch-show-message-unread-p))
-      (notmuch-show-next-message)))
+      (notmuch-show-next-message-without-marking-read))
+  (notmuch-show-mark-read))
 
 (defun notmuch-show-next-open-message ()
   "Advance to the next open message (that is, body is not invisible)."
-  (while (and (notmuch-show-next-message)
-	      (not (notmuch-show-message-open-p)))))
+  (while (and (notmuch-show-next-message-without-marking-read)
+	      (not (notmuch-show-message-open-p))))
+  (notmuch-show-mark-read))
 
 (defun notmuch-show-previous-message ()
   "Backup to the beginning of the previous message in the buffer.