master 078cfe80729 2/2: Preserve point when inserting date stamps in ERC

[F. Jason Park]

branch: master
commit 078cfe807295038fa321c9297e24de5145065622
Author: F. Jason Park <jp@neverwas.me>
Commit: F. Jason Park <jp@neverwas.me>

    Preserve point when inserting date stamps in ERC
    
    * lisp/erc/erc-stamp.el (erc-stamp-mode, erc-stamp-disable): Move
    remaining local teardown business to `erc-stamp--setup' and use
    `erc-buffer-do' instead of `erc-with-all-buffers-of-server' to
    emphasize that all ERC buffers are affected.
    (erc-stamp--insert-date-stamp-as-phony-message): Move `erc--msg-props'
    binding to `erc-stamp--lr-date-on-pre-modify'.
    (erc-stamp--lr-date-on-pre-modify): Bind `erc--msg-props' here so that
    the related guard condition in `erc-add-timestamp' is satisfied and
    `erc-insert-timestamp-function' runs.  This fixes a regression new in
    ERC 5.6 and introduced by c68dc778 "Manage some text props for ERC
    insertion-hook members".  Also, `save-excursion' when narrowing to
    prevent point from being dislodged after submitting input at the
    prompt.
    (erc-insert-timestamp-left-and-right): Don't initialize date stamps
    when `erc-timestamp-format-left' is nil or consists only of newlines,
    and enable fallback behavior in such cases on behalf of users without
    informing them.  Allow global hook members to run first so that those
    owned by `scrolltobottom' and similar can see the unadulterated input.
    Fix wrong hook name.
    (erc-stamp--setup): Fix wrong hook name.  Kill all local vars here
    instead of sharing this duty with the minor-mode toggle.  (Bug#60936)
---
 lisp/erc/erc-stamp.el | 43 ++++++++++++++++++++++++-------------------
 1 file changed, 24 insertions(+), 19 deletions(-)

diff --git a/lisp/erc/erc-stamp.el b/lisp/erc/erc-stamp.el
index b3812470a4d..412740ac192 100644
--- a/lisp/erc/erc-stamp.el
+++ b/lisp/erc/erc-stamp.el
@@ -187,12 +187,7 @@ from entering them and instead jump over them."
    (remove-hook 'erc-send-modify-hook #'erc-add-timestamp)
    (remove-hook 'erc-mode-hook #'erc-stamp--recover-on-reconnect)
    (remove-hook 'erc--pre-clear-functions #'erc-stamp--reset-on-clear)
-   (erc-with-all-buffers-of-server nil nil
-     (erc-stamp--setup)
-     (kill-local-variable 'erc-stamp--last-stamp)
-     (kill-local-variable 'erc-timestamp-last-inserted)
-     (kill-local-variable 'erc-timestamp-last-inserted-left)
-     (kill-local-variable 'erc-timestamp-last-inserted-right))))
+   (erc-buffer-do #'erc-stamp--setup)))
 
 (defvar erc-stamp--invisible-property nil
   "Existing `invisible' property value and/or symbol `timestamp'.")
@@ -664,11 +659,7 @@ printed just after each line's text (no alignment)."
 (defun erc-stamp--insert-date-stamp-as-phony-message (string)
   (cl-assert (string-empty-p string))
   (setq string erc-stamp--current-datestamp-left)
-  (cl-assert string)
   (let ((erc-stamp--skip t)
-        (erc--msg-props (map-into `((erc-msg . datestamp)
-                                    (erc-ts . ,(erc-stamp--current-time)))
-                                  'hash-table))
         (erc-insert-modify-hook `(,@erc-insert-modify-hook
                                   erc-stamp--propertize-left-date-stamp))
         ;; Don't run hooks that aren't expecting a narrowed buffer.
@@ -684,11 +675,17 @@ printed just after each line's text (no alignment)."
              (erc-stamp--current-datestamp-left rendered)
              (erc-insert-timestamp-function
               #'erc-stamp--insert-date-stamp-as-phony-message))
-    (save-restriction
-      (narrow-to-region (or erc--insert-marker erc-insert-marker)
-                        (or erc--insert-marker erc-insert-marker))
-      (let (erc-timestamp-format erc-away-timestamp-format)
-        (erc-add-timestamp)))))
+    (save-excursion
+      (save-restriction
+        (narrow-to-region (or erc--insert-marker erc-insert-marker)
+                          (or erc--insert-marker erc-insert-marker))
+        ;; Forget current `erc-cmd', etc.
+        (let ((erc--msg-props
+               (map-into `((erc-msg . datestamp)
+                           (erc-ts . ,(erc-stamp--current-time)))
+                         'hash-table))
+              erc-timestamp-format erc-away-timestamp-format)
+          (erc-add-timestamp))))))
 
 (defvar erc-stamp-prepend-date-stamps-p nil
   "When non-nil, date stamps are not independent messages.
@@ -714,9 +711,13 @@ requirements related to `erc-legacy-invisible-bounds-p'.
 Additionally, ensure every date stamp is identifiable as such so
 that internal modules can easily distinguish between other
 left-sided stamps and date stamps inserted by this function."
-  (unless (or erc-stamp--date-format-end erc-stamp-prepend-date-stamps-p)
-    (add-hook 'erc-insert-pre-hook #'erc-stamp--lr-date-on-pre-modify -95 t)
-    (add-hook 'erc-send-pre-functions #'erc-stamp--lr-date-on-pre-modify -95 t)
+  (unless (or erc-stamp--date-format-end erc-stamp-prepend-date-stamps-p
+              (and (or (null erc-timestamp-format-left)
+                       (string-empty-p ; compat
+                        (string-trim erc-timestamp-format-left "\n")))
+                   (setq erc-stamp-prepend-date-stamps-p t)))
+    (add-hook 'erc-insert-pre-hook #'erc-stamp--lr-date-on-pre-modify 10 t)
+    (add-hook 'erc-pre-send-functions #'erc-stamp--lr-date-on-pre-modify 10 t)
     (let ((erc--insert-marker (point-min-marker))
           (end-marker (point-max-marker)))
       (set-marker-insertion-type erc--insert-marker t)
@@ -817,7 +818,11 @@ Return the empty string if FORMAT is nil."
       (erc-munge-invisibility-spec))
     ;; Undo local mods from `erc-insert-timestamp-left-and-right'.
     (remove-hook 'erc-insert-pre-hook #'erc-stamp--lr-date-on-pre-modify t)
-    (remove-hook 'erc-send-pre-functions #'erc-stamp--lr-date-on-pre-modify t)
+    (remove-hook 'erc-pre-send-functions #'erc-stamp--lr-date-on-pre-modify t)
+    (kill-local-variable 'erc-stamp--last-stamp)
+    (kill-local-variable 'erc-timestamp-last-inserted)
+    (kill-local-variable 'erc-timestamp-last-inserted-left)
+    (kill-local-variable 'erc-timestamp-last-inserted-right)
     (kill-local-variable 'erc-stamp--date-format-end)))
 
 (defun erc-hide-timestamps ()