master 47612514a9e 5/8: Fix right-sided stamps commingling with erc-prompt

[F. Jason Park]

branch: master
commit 47612514a9e04d6f41568c3f0cdeae837c2eae19
Author: F. Jason Park <jp@neverwas.me>
Commit: F. Jason Park <jp@neverwas.me>

    Fix right-sided stamps commingling with erc-prompt
    
    * lisp/erc/erc-stamp.el (erc-insert-timestamp-left-and-right): Fix bug
    that saw the prompt being inserted after messages but just inside the
    narrowed operating portion of the buffer, which meant remaining
    modification hooks would see it upon visiting.  Thanks to Corwin Brust
    for catching this.
    * test/lisp/erc/erc-fill-tests.el (erc-fill-wrap--monospace): Use
    custom `erc-prompt' function to guarantee invariants asserted by
    `erc--assert-input-bounds' are preserved throughout.  (Bug#60936)
---
 lisp/erc/erc-stamp.el           |  6 +++--
 test/lisp/erc/erc-fill-tests.el | 57 ++++++++++++++++++++++-------------------
 2 files changed, 34 insertions(+), 29 deletions(-)

diff --git a/lisp/erc/erc-stamp.el b/lisp/erc/erc-stamp.el
index 57fd7f39e50..c8fd7c35392 100644
--- a/lisp/erc/erc-stamp.el
+++ b/lisp/erc/erc-stamp.el
@@ -704,10 +704,12 @@ left-sided stamps and date stamps inserted by this 
function."
   (unless erc-stamp--date-format-end
     (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)
-    (let ((erc--insert-marker (point-min-marker)))
+    (let ((erc--insert-marker (point-min-marker))
+          (end-marker (point-max-marker)))
       (set-marker-insertion-type erc--insert-marker t)
       (erc-stamp--lr-date-on-pre-modify nil)
-      (narrow-to-region erc--insert-marker (point-max))
+      (narrow-to-region erc--insert-marker end-marker)
+      (set-marker end-marker nil)
       (set-marker erc--insert-marker nil)))
   (let* ((ct (or erc-stamp--current-time (erc-stamp--current-time)))
          (ts-right (with-suppressed-warnings
diff --git a/test/lisp/erc/erc-fill-tests.el b/test/lisp/erc/erc-fill-tests.el
index f6c4c268017..80f5fd22ac6 100644
--- a/test/lisp/erc/erc-fill-tests.el
+++ b/test/lisp/erc/erc-fill-tests.el
@@ -203,36 +203,39 @@
   (unless (>= emacs-major-version 29)
     (ert-skip "Emacs version too low, missing `buffer-text-pixel-size'"))
 
-  (erc-fill-tests--wrap-populate
-
-   (lambda ()
-     (should (= erc-fill--wrap-value 27))
-     (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
-     (erc-fill-tests--compare "monospace-01-start")
-
-     (ert-info ("Shift right by one (plus)")
-       ;; Args are all `erc-fill-wrap-nudge' +1 because interactive "p"
-       (ert-with-message-capture messages
-         ;; M-x erc-fill-wrap-nudge RET =
-         (ert-simulate-command '(erc-fill-wrap-nudge 2))
-         (should (string-match (rx "for further adjustment") messages)))
-       (should (= erc-fill--wrap-value 29))
-       (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
-       (erc-fill-tests--compare "monospace-02-right"))
-
-     (ert-info ("Shift left by five")
-       ;; "M-x erc-fill-wrap-nudge RET -----"
-       (ert-simulate-command '(erc-fill-wrap-nudge -4))
-       (should (= erc-fill--wrap-value 25))
-       (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
-       (erc-fill-tests--compare "monospace-03-left"))
+  (let ((erc-prompt (lambda () "ABC>")))
+    (erc-fill-tests--wrap-populate
 
-     (ert-info ("Reset")
-       ;; M-x erc-fill-wrap-nudge RET 0
-       (ert-simulate-command '(erc-fill-wrap-nudge 0))
+     (lambda ()
        (should (= erc-fill--wrap-value 27))
        (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
-       (erc-fill-tests--compare "monospace-04-reset")))))
+       (erc-fill-tests--compare "monospace-01-start")
+
+       (ert-info ("Shift right by one (plus)")
+         ;; Args are all `erc-fill-wrap-nudge' +1 because interactive "p"
+         (ert-with-message-capture messages
+           ;; M-x erc-fill-wrap-nudge RET =
+           (ert-simulate-command '(erc-fill-wrap-nudge 2))
+           (should (string-match (rx "for further adjustment") messages)))
+         (should (= erc-fill--wrap-value 29))
+         (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
+         (erc-fill-tests--compare "monospace-02-right"))
+
+       (ert-info ("Shift left by five")
+         ;; "M-x erc-fill-wrap-nudge RET -----"
+         (ert-simulate-command '(erc-fill-wrap-nudge -4))
+         (should (= erc-fill--wrap-value 25))
+         (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
+         (erc-fill-tests--compare "monospace-03-left"))
+
+       (ert-info ("Reset")
+         ;; M-x erc-fill-wrap-nudge RET 0
+         (ert-simulate-command '(erc-fill-wrap-nudge 0))
+         (should (= erc-fill--wrap-value 27))
+         (erc-fill-tests--wrap-check-prefixes "*** " "<alice> " "<bob> ")
+         (erc-fill-tests--compare "monospace-04-reset"))
+
+       (erc--assert-input-bounds)))))
 
 (defun erc-fill-tests--simulate-refill ()
   ;; Simulate `erc-fill-wrap-refill-buffer' synchronously and without