Fix bug: don't mistakenly say that a folder is unchanged by reading

the modification count at the wrong time.

diff --git a/v7/src/imail/imail-top.scm b/v7/src/imail/imail-top.scm
index e69fbd431392f79530221d72f68d96addae7a084..bd14be822cd430e20623312c1738c3a8fed451f0 100644 (file)
--- a/v7/src/imail/imail-top.scm
+++ b/v7/src/imail/imail-top.scm
@@ -1,6 +1,6 @@
 ;;; -*-Scheme-*-
 ;;;
-;;; $Id: imail-top.scm,v 1.88 2000/05/22 20:57:22 cph Exp $
+;;; $Id: imail-top.scm,v 1.89 2000/05/22 22:41:00 cph Exp $
 ;;;
 ;;; Copyright (c) 1999-2000 Massachusetts Institute of Technology
 ;;;
@@ -1144,26 +1144,31 @@ Selects the first new message if any new mail.
 Currently useful only for IMAP folders."
   ()
   (lambda ()
-    (let ((folder (selected-folder)))
-      (let ((count (folder-modification-count folder))
-           (last (navigator/last-message folder)))
-       (probe-folder folder)
-       (if (> (folder-modification-count folder) count)
-           (select-message
-            folder
-            (or (cond ((not last)
-                       (navigator/first-message folder))
-                      ((message-attached? last folder)
-                       (navigator/next-message last))
-                      ((message-index last)
-                       => (lambda (index)
-                            (let ((index (+ index 1)))
-                              (if (< index (folder-length folder))
-                                  (get-message folder index)
-                                  (navigator/first-unseen-message folder)))))
-                      (else (navigator/first-unseen-message folder)))
-                (selected-message #f)))
-           (message "(No changes to mail folder)"))))))
+    (let* ((folder (selected-folder))
+          (count (folder-modification-count folder))
+          ;; NAVIGATOR/LAST-MESSAGE must run _after_
+          ;; FOLDER-MODIFICATION-COUNT as it can potentially change
+          ;; its value.  (E.g. when IMAP folder is closed, this
+          ;; reopens it, reads new information from the server, and
+          ;; changes the modification count.)
+          (last (navigator/last-message folder)))
+      (probe-folder folder)
+      (if (> (folder-modification-count folder) count)
+         (select-message
+          folder
+          (or (cond ((not last)
+                     (navigator/first-message folder))
+                    ((message-attached? last folder)
+                     (navigator/next-message last))
+                    ((message-index last)
+                     => (lambda (index)
+                          (let ((index (+ index 1)))
+                            (if (< index (folder-length folder))
+                                (get-message folder index)
+                                (navigator/first-unseen-message folder)))))
+                    (else (navigator/first-unseen-message folder)))
+              (selected-message #f)))
+         (message "(No changes to mail folder)")))))
 
 (define-command imail-save-folder
   "Save the currently selected IMAIL folder."