* clear up the mu4e headers updating mechanism, so it's more robust (i.e..,

when another window is selected, such as in the case when using the
  speedbar).

  Also, some cleanup in message composition (that would deserve a separate
  commit, but it's too late now...)

emacs/mu4e-hdrs.el

@@ -45,6 +45,17 @@
 (defconst mu4e-hdrs-fringe "  "
   "*internal* The space on the left of message headers to put marks.")
 
+(defun mu4e-hdrs-clear ()
+  "Clear the header buffer and related data structures."
+  (when (buffer-live-p mu4e-hdrs-buffer)
+    (let ((inhibit-read-only t))
+      (with-current-buffer mu4e-hdrs-buffer
+	(erase-buffer)
+	(when mu4e-marks-map (clrhash mu4e-marks-map))
+	(when mu4e-msg-map (clrhash mu4e-msg-map))
+	(when mu4e-thread-info-map (clrhash mu4e-thread-info-map))))))
+
+
 (defun mu4e-hdrs-search (expr &optional full-search)
   "Search in the mu database for EXPR, and switch to the output
 buffer for the results. If FULL-SEARCH is non-nil return all
@@ -54,14 +65,14 @@ results, otherwise, limit number of results to
 	  (inhibit-read-only t)
 	 (esc (replace-regexp-in-string "\"" "\\\\\"" expr))) ;; escape "\"
     (with-current-buffer buf
-      (erase-buffer)
       (mu4e-hdrs-mode)
       (setq
 	global-mode-string (propertize expr 'face 'mu4e-title-face)
 	mu4e-last-expr expr
 	mu4e-hdrs-buffer buf
 	mode-name "mu4e-headers"))
-    (switch-to-buffer mu4e-hdrs-buffer)
+
+    (switch-to-buffer buf)
     (mu4e-proc-find esc ;; '-1' means 'unlimited search'
       (if full-search -1 mu4e-search-results-limit))))
 
@@ -95,8 +106,9 @@ headers."
 	      (point (when marker (marker-position marker))))
 	(when point ;; is the message present in this list?
 	  ;; if it's marked, unmark it now
-	  (when (mu4e-hdrs-docid-is-marked docid) (mu4e-hdrs-mark 'unmark))
-	  ;; first, remove the old one (otherwise, we'd have to headers with
+	  (when (mu4e-hdrs-docid-is-marked docid)
+	    (mu4e-hdrs-mark 'unmark))
+	  ;; first, remove the old one (otherwise, we'd have two headers with
 	  ;; the same docid...
 	  (mu4e-hdrs-remove-handler docid)
 
@@ -120,7 +132,7 @@ headers."
 
 (defun mu4e-hdrs-remove-handler (docid)
   "Remove handler, will be called when a message has been removed
-from the database. This function will hide the remove message in
+from the database. This function will hide the removed message from
 the current list of headers."
   (with-current-buffer mu4e-hdrs-buffer
     (let* ((marker (gethash docid mu4e-msg-map))
@@ -128,7 +140,7 @@ the current list of headers."
 	    (docid-at-pos (and pos (mu4e-hdrs-get-docid pos))))
       (unless marker (error "Message %d not found" docid))
       (unless (eq docid docid-at-pos)
-	(error "At point %d, expected docid %d, but got %d"
+	(error "At point %d, expected docid %d, but got %S"
 	  pos docid docid-at-pos))
       (mu4e-hdrs-remove-header docid pos))))
 
@@ -164,7 +176,7 @@ into a string."
 (defun mu4e-hdrs-header-handler (msg &optional point)
   "Create a one line description of MSG in this buffer, at POINT,
 if provided, or at the end of the buffer otherwise."
-  (let* ( (docid (plist-get msg :docid))
+  (let* ((docid (plist-get msg :docid))
 	  (thread-info
 	    (or (plist-get msg :thread) (gethash docid mu4e-thread-info-map)))
 	  (line
@@ -210,9 +222,8 @@ if provided, or at the end of the buffer otherwise."
     ;; store the thread info, so we can use it when updating the message
     (when  (and thread-info mu4e-thread-info-map)
       (puthash docid thread-info mu4e-thread-info-map))
-    (mu4e-hdrs-add-header line (plist-get msg :docid)
-      (if point point (point-max)))))
-
+    ;; now, append the header line
+    (mu4e-hdrs-add-header line docid point)))
 
 (defun mu4e-hdrs-found-handler (count)
   "Create a one line description of the number of headers found
@@ -278,7 +289,7 @@ after the end of the search results."
       (define-key map "R" 'mu4e-compose-reply)
       (define-key map "F" 'mu4e-compose-forward)
       (define-key map "C" 'mu4e-compose-new)
-      (define-key map "E" 'mu4e-edit-draft)
+      (define-key map "E" 'mu4e-compose-edit)
 
       (define-key map (kbd "RET") 'mu4e-view-message)
       (define-key map [mouse-2]   'mu4e-view-message)
@@ -325,7 +336,6 @@ after the end of the search results."
 	(define-key menumap [previous]  '("Previous" . mu4e-prev-header))
 	(define-key menumap [sepa4] '("--")))
 
-	;;(define-key menumap [draft]  '("Edit draft" . mu4e-compose-new))
       map)))
 
 (fset 'mu4e-hdrs-mode-map mu4e-hdrs-mode-map)
@@ -337,6 +347,8 @@ after the end of the search results."
 (setq mu4e-proc-found-func   'mu4e-hdrs-found-handler)
 (setq mu4e-proc-view-func    'mu4e-hdrs-view-handler)
 (setq mu4e-proc-remove-func  'mu4e-hdrs-remove-handler)
+(setq mu4e-proc-erase-func   'mu4e-hdrs-clear)
+
 ;; this last one is defined in mu4e-send.el
 (setq mu4e-proc-compose-func 'mu4e-send-compose-handler)
 
@@ -391,23 +403,40 @@ after the end of the search results."
 (defvar mu4e-msg-map nil
   "*internal* A map (hashtable) which maps a database (Xapian)
 docid (which uniquely identifies a message to a marker.  where
-marker points to the buffer position for the message.
+marker points to the buffer position for the message
 
 Using this map, we can update message headers which are currently
 on the screen, when we receive (:update ) notices from the mu
 server.")
 
+(defun mu4e-select-headers-window-if-visible ()
+  "When there is a visible window for the headers buffer, make sure
+to select it. This is needed when adding new headers, otherwise
+adding a lot of new headers looks really choppy."
+  (let ((win (get-buffer-window mu4e-hdrs-buffer)))
+    (when win (select-window win)
+)))
+
+
 (defun mu4e-hdrs-add-header (str docid point)
-  "Add header STR with DOCID to the buffer at POINT."
+  "Add header STR with DOCID to the buffer at POINT if non-nil, or
+at (point-max) otherwise."
   (unless docid (error "Invalid message"))
   (when (buffer-live-p mu4e-hdrs-buffer)
     (with-current-buffer mu4e-hdrs-buffer
-      (let ((inhibit-read-only t))
+      (let ((inhibit-read-only t) (point (if point point (point-max))))
+ 	;;(mu4e-select-headers-window-if-visible)
 	(save-excursion
 	  (goto-char point)
+	  ;; make sure the output window is selected, which it wouldn't be if called
+	  ;; from e.g. speedbar (output looks choppy when another window is
+	  ;; selected). We use switch-to-buffer for its window-selecting side-effect -
+	  ;; but only if the window is visible
+
+	  (insert (propertize (concat mu4e-hdrs-fringe str "\n")  'docid docid))
 	  ;; Update `mu4e-msg-map' with MSG, and MARKER pointing to the buffer
 	  ;; position for the message header."
-	  (insert (propertize (concat mu4e-hdrs-fringe str "\n")  'docid docid))
+
 	  ;; note: this maintaining the hash with the markers makes things slow
 	  ;; when there are many (say > 1000) headers. this seems to be mostly
 	  ;; in the use of markers. we use those to find messages when they need
@@ -436,7 +465,8 @@ server.")
     (when marker
       (with-current-buffer mu4e-hdrs-buffer
 	(save-excursion
-	  (let ((inhibit-read-only t) (pos (marker-position marker)))
+	  (let ((inhibit-read-only t)
+		 (pos (marker-position marker)))
 	    (goto-char pos)
 	    (delete-char 2)
 	    (insert (propertize mark 'face 'mu4e-hdrs-marks-face) " ")
@@ -598,30 +628,6 @@ work well."
     (unless docid (error "No message at point."))
     (mu4e-proc-view-msg docid)))
 
-
-(defun mu4e-hdrs-compose (compose-type)
-  "Compose either a reply/forward based on the message at point. or
-start editing it. COMPOSE-TYPE is either `reply', `forward', `edit'
-or `new'."
-  (if (eq compose-type 'new)
-    (mu4e-send-compose-handler 'new)
-    (let ((docid (mu4e-hdrs-get-docid))
-	   ;; note, the first two chars of the line (the mark margin) does *not*
-	   ;; have the 'draft property; thus, we check one char before the end of
-	   ;; the current line instead
-	   (is-draft (get-text-property (- (line-end-position) 1) 'draft)))
-      (unless docid
-	(error "No message at point."))
-      (cond
-	((member compose-type '(reply forward))
-	  (mu4e-proc-compose compose-type docid))
-	((eq compose-type 'edit)
-	  (unless is-draft
-	    (error "Cannot edit a non-draft message"))
-	  (mu4e-proc-compose 'edit docid))
-	(t (error "invalid compose type %S" compose-type))))))
-
-
 (defun mu4e-hdrs-docid-is-marked (docid)
   "Is the given docid marked?"
   (when (gethash docid mu4e-marks-map) t))
@@ -671,8 +677,8 @@ up to `mu4e-search-results-limit' much quicker."
       (mu4e-hdrs-search expr current-prefix-arg)))
 
 (defun mu4e-search-bookmark ()
-  "Search using some bookmarked query. With C-u prefix, show /all/ results, otherwise,
-limit to up to `mu4e-search-results-limit'."
+  "Search using some bookmarked query. With C-u prefix, show /all/ results,
+otherwise, limit to up to `mu4e-search-results-limit'."
   (interactive)
   (let ((query (mu4e-ask-bookmark "Bookmark: ")))
     (when query
@@ -808,28 +814,52 @@ parameter NO-CONFIRMATION is is t, don't ask for confirmation."
 	(mu4e-hdrs-marks-execute)
 	(message nil)))))
 
-(defun mu4e-compose-reply ()
-  "Start composing a reply to the current message."
+
+(defun mu4e-compose (&optional compose-type)
+  "Start composing a message of COMPOSE-TYPE, where COMPOSE-TYPE is
+a symbol, one of `reply', `forward', `edit', `new'. All but `new'
+take the message at point as input. Symbol `edit' is only allowed
+for draft messages."
   (interactive)
-  (with-current-buffer mu4e-hdrs-buffer
-    (mu4e-hdrs-compose 'reply)))
+  (let ((compose-type
+	  (or compose-type
+	    (intern (ido-completing-read "Compose type: "
+		      '("reply" "forward" "edit" "new"))))))
+    (with-current-buffer mu4e-hdrs-buffer
+      ;; 'new is special, since it takes no existing message as arg therefore,
+      ;; we don't need to call thec backend, and call the handler *directly*
+      (if (eq compose-type 'new)
+	(mu4e-send-compose-handler 'new)
+	;; otherwise, we need the doc-id
+	(let ((docid (mu4e-hdrs-get-docid))
+	       (is-draft ))
+	  (unless docid (error "No message at point."))
+
+	  ;; note, the first two chars of the line (the mark margin) does *not*
+	  ;; have the 'draft property; thus, we check one char before the end of
+	  ;; the current line instead
+	  (when (and (eq compose-type 'edit)
+		  (get-text-property (- (line-end-position) 1) 'draft))
+	    (error "Editing only allowed for draft messages"))
+	  ;; talk to the backend
+	  (mu4e-proc-compose compose-type docid))))))
+
+
+(defun mu4e-compose-reply ()
+  "Reply to the current message."
+  (interactive) (mu4e-compose 'reply))
 
 (defun mu4e-compose-forward ()
-  "Start composing a forward to the current message."
-  (interactive)
-  (with-current-buffer mu4e-hdrs-buffer
-    (mu4e-hdrs-compose 'forward)))
+  "Forward the current message."
+  (interactive) (mu4e-compose 'forward))
+
+(defun mu4e-compose-edit ()
+  "Edit the draft message."
+  (interactive) (mu4e-compose 'edit))
 
 (defun mu4e-compose-new ()
-  "Compose a new, empty message."
-  (interactive)
-  (mu4e-hdrs-compose 'new))
-
-(defun mu4e-edit-draft ()
-  "Start editing the existing draft message at point."
-  (interactive)
-  (with-current-buffer mu4e-hdrs-buffer
-    (mu4e-hdrs-compose 'edit)))
+  "Compose a new message."
+  (interactive) (mu4e-compose 'new))
 
 
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