From 6b2bdf4f6dee62f13f1442f9be512888326026ea Mon Sep 17 00:00:00 2001
From: "Dirk-Jan C. Binnema" <djcb@djcbsoftware.nl>
Date: Thu, 27 Feb 2020 23:10:02 +0200
Subject: [PATCH] mu4e: avoid some errors when flipping through messages

Use special-mode for the loading buffer, and explicitly ignore n/p.

Fixes #1443.
Fixes #1217.
---
 mu4e/mu4e-headers.el | 25 +++++++------------------
 mu4e/mu4e-view.el    | 29 ++++++++++++++++++++++++++++-
 2 files changed, 35 insertions(+), 19 deletions(-)

diff --git a/mu4e/mu4e-headers.el b/mu4e/mu4e-headers.el
index e9e42d08..02a0bd3e 100644
--- a/mu4e/mu4e-headers.el
+++ b/mu4e/mu4e-headers.el
@@ -1659,23 +1659,6 @@ _not_ refresh the last search with the new setting for threading."
 (defvar mu4e~headers-loading-buf nil
   "A buffer for loading a message view.")
 
-(defun mu4e~headers-get-loading-buf ()
-  "Get a buffer to give feedback while loading a message view."
-  (unless (buffer-live-p mu4e~headers-loading-buf)
-    (setq mu4e~headers-loading-buf
-          (get-buffer-create " *mu4e-loading*")))
-  (with-current-buffer mu4e~headers-loading-buf
-    (read-only-mode)
-    (let ((inhibit-read-only t))
-      (erase-buffer)
-      (local-set-key (kbd "q")
-                     (if (eq mu4e-split-view 'single-window)
-                         'kill-buffer
-                       'kill-buffer-and-window))
-      (insert (propertize "Waiting for message..."
-                          'face 'mu4e-system-face 'intangible t))))
-  mu4e~headers-loading-buf)
-
 (defun mu4e~decrypt-p (msg)
   "Should we decrypt this message?"
   (and (member 'encrypted (mu4e-message-field msg :flags))
@@ -1701,7 +1684,13 @@ window. "
     (unless (window-live-p viewwin)
       (mu4e-error "Cannot get a message view"))
     (select-window viewwin)
-    (switch-to-buffer (mu4e~headers-get-loading-buf))
+
+    (unless (buffer-live-p mu4e~headers-loading-buf)
+      (setq mu4e~headers-loading-buf (get-buffer-create " *mu4e-loading*"))
+      (with-current-buffer mu4e~headers-loading-buf
+        (mu4e-loading-mode)))
+
+    (switch-to-buffer mu4e~headers-loading-buf)
     ;; Note, ideally in the 'gnus' case, we don't need to call the server to get
     ;; the body etc., we only need the path which we already have.
     ;;
diff --git a/mu4e/mu4e-view.el b/mu4e/mu4e-view.el
index 686f2f6d..4fa8cf0f 100644
--- a/mu4e/mu4e-view.el
+++ b/mu4e/mu4e-view.el
@@ -1771,6 +1771,33 @@ other windows."
           (when (buffer-live-p (mu4e-get-headers-buffer))
             (switch-to-buffer (mu4e-get-headers-buffer))))))))
 
-;;; _
+;;
+;; Loading messages
+;;
+
+(defvar mu4e-loading-mode-map nil  "Keymap for *mu4e-loading* buffers.")
+(unless mu4e-loading-mode-map
+  (setq mu4e-loading-mode-map
+        (let ((map (make-sparse-keymap)))
+          (define-key map "n" 'ignore)
+          (define-key map "p" 'ignore)
+          (define-key map "q"
+            (lambda()(interactive)
+              (if (eq mu4e-split-view 'single-window)
+                  'kill-buffer
+                'kill-buffer-and-window)))
+          map)))
+(fset 'mu4e-loading-mode-map mu4e-loading-mode-map)
+
+(define-derived-mode mu4e-loading-mode special-mode
+  "mu4e:loading"
+  (use-local-map mu4e-loading-mode-map)
+  (make-local-variable 'global-mode-string)
+  (let ((inhibit-read-only t))
+    (erase-buffer)
+    (insert (propertize "Loading message..."
+                        'face 'mu4e-system-face 'intangible t))))
+
+;;;
 (provide 'mu4e-view)
 ;;; mu4e-view.el ends here