[elpa] externals/ement cff1c9b45f 1/2: Change: (ement-room-scroll-up-mark-read) Move f-r marker to TOW

[ELPA Syncer]

branch: externals/ement
commit cff1c9b45f8b8d744c40453cad91ff67a479fb0c
Author: Adam Porter <adam@alphapapa.net>
Commit: Adam Porter <adam@alphapapa.net>

    Change: (ement-room-scroll-up-mark-read) Move f-r marker to TOW
---
 README.org    |  1 +
 ement-room.el | 84 ++++++++++++++++++++++++++++++++++-------------------------
 2 files changed, 49 insertions(+), 36 deletions(-)

diff --git a/README.org b/README.org
index 2a5120686e..430b6fb446 100644
--- a/README.org
+++ b/README.org
@@ -307,6 +307,7 @@ Note that, while ~matrix-client~ remains usable, and 
probably will for some time
 + Command ~ement-view-room~, when used for a space, shows a footer explaining 
that the buffer is showing a space rather than a normal room, with a button to 
call ~ement-view-space~ for it (which lists rooms in the space).
 + Command ~ement-describe-room~ shows whether a room is a space or a normal 
room.
 + Command ~ement-view-space~ shows the space's name and alias.
++ Command ~ement-room-scroll-up-mark-read~ moves the fully read marker to the 
top of the window (when the marker's position is within the range of known 
events), rather than only moving it when at the end of the buffer.  (This eases 
the process of gradually reading a long backlog of messages.)
 + Improve readme export settings.
 
 *Fixes*
diff --git a/ement-room.el b/ement-room.el
index 772111cb4a..eaaf2f1ff2 100644
--- a/ement-room.el
+++ b/ement-room.el
@@ -1273,42 +1273,6 @@ otherwise use current room."
                                        "m.image"
                                      "m.file"))))
 
-(declare-function ement-tabulated-room-list-next-unread 
"ement-tabulated-room-list")
-(declare-function ement-room-list-next-unread "ement-room-list")
-(defun ement-room-scroll-up-mark-read ()
-  "Scroll buffer up, marking read and burying when at end."
-  (interactive)
-  (if (= (window-point) (point-max))
-      (progn
-        ;; At the bottom of the buffer: mark read and show next unread room.
-        (when ement-room-mark-rooms-read
-          (ement-room-mark-read ement-room ement-session
-            :read-event (ewoc-data (ement-room--ewoc-last-matching ement-ewoc
-                                     (lambda (data) (ement-event-p data))))
-            :fully-read-event (ewoc-data (ement-room--ewoc-last-matching 
ement-ewoc
-                                           (lambda (data) (ement-event-p 
data))))))
-        (set-buffer-modified-p nil)
-        (if-let ((rooms-window (cl-find-if (lambda (window)
-                                             (member (buffer-name 
(window-buffer window))
-                                                     '("*Ement Taxy*" "*Ement 
Rooms*")))
-                                           (window-list))))
-            ;; Rooms buffer already displayed: select its window and move to 
next unread room.
-            (progn
-              (select-window rooms-window)
-              (funcall (pcase-exhaustive major-mode
-                         ('ement-tabulated-room-list-mode 
#'ement-tabulated-room-list-next-unread)
-                         ('ement-room-list-mode 
#'ement-room-list-next-unread))))
-          ;; Rooms buffer not displayed: bury this room buffer, which should 
usually
-          ;; result in another room buffer or the rooms list buffer being 
displayed.
-          (bury-buffer))
-        (when (member major-mode '(ement-tabulated-room-list-mode 
ement-room-list-mode))
-          ;; Back in the room-list buffer: revert it.
-          (revert-buffer)))
-    ;; Not at the bottom of the buffer: scroll.
-    (condition-case _err
-        (scroll-up-command)
-      (end-of-buffer (set-window-point nil (point-max))))))
-
 (cl-defun ement-room-join (id-or-alias session &key then)
   "Join room by ID-OR-ALIAS on SESSION.
 THEN may be a function to call after joining the room (and when
@@ -2813,6 +2777,54 @@ updates the markers in ROOM's buffer, not on the server; 
see
     ;; big and/or circular to print.  (This was one of those bugs that only 
happens WHEN debugging.)
     nil))
 
+(defun ement-room-scroll-up-mark-read ()
+  "Scroll buffer contents up, move fully read marker, and bury when at end.
+Moves fully read marker to the top of the window (when the
+marker's position is within the range of received events).  At
+end-of-buffer, moves fully read marker to after the last event,
+buries the buffer and shows the next unread room, if any."
+  (declare (function ement-tabulated-room-list-next-unread 
"ement-tabulated-room-list")
+           (function ement-room-list-next-unread "ement-room-list"))
+  (interactive)
+  (if (= (window-point) (point-max))
+      (progn
+        ;; At the bottom of the buffer: mark read and show next unread room.
+        (when ement-room-mark-rooms-read
+          (ement-room-mark-read ement-room ement-session
+            :read-event (ewoc-data (ement-room--ewoc-last-matching ement-ewoc
+                                     (lambda (data) (ement-event-p data))))
+            :fully-read-event (ewoc-data (ement-room--ewoc-last-matching 
ement-ewoc
+                                           (lambda (data) (ement-event-p 
data))))))
+        (set-buffer-modified-p nil)
+        (if-let ((rooms-window (cl-find-if (lambda (window)
+                                             (member (buffer-name 
(window-buffer window))
+                                                     '("*Ement Taxy*" "*Ement 
Rooms*")))
+                                           (window-list))))
+            ;; Rooms buffer already displayed: select its window and move to 
next unread room.
+            (progn
+              (select-window rooms-window)
+              (funcall (pcase-exhaustive major-mode
+                         ('ement-tabulated-room-list-mode 
#'ement-tabulated-room-list-next-unread)
+                         ('ement-room-list-mode 
#'ement-room-list-next-unread))))
+          ;; Rooms buffer not displayed: bury this room buffer, which should 
usually
+          ;; result in another room buffer or the rooms list buffer being 
displayed.
+          (bury-buffer))
+        (when (member major-mode '(ement-tabulated-room-list-mode 
ement-room-list-mode))
+          ;; Back in the room-list buffer: revert it.
+          (revert-buffer)))
+    ;; Not at the bottom of the buffer: scroll.
+    (condition-case _err
+        (scroll-up-command)
+      (end-of-buffer (set-window-point nil (point-max))))
+    (when-let* ((node (ewoc-locate ement-ewoc (window-start)))
+                (event-node (ement-room--ewoc-next-matching ement-ewoc node
+                              #'ement-event-p #'ewoc-prev))
+                (fully-read-pos (and ement-room-fully-read-marker
+                                     (ewoc-location 
ement-room-fully-read-marker)))
+                ((< fully-read-pos (ewoc-location event-node))))
+      ;; Move fully-read marker to top of window.
+      (ement-room-mark-read ement-room ement-session :fully-read-event 
(ewoc-data event-node)))))
+
 ;;;;; EWOC
 
 (cl-defun ement-room--ewoc-next-matching (ewoc node pred &optional (move-fn 
#'ewoc-next))