* lisp/isearch.el: Improve 'isearch-allow-motion' feature (bug#50466)

* lisp/isearch.el: Add recenter to 'isearch-motion' property of
'end-of-buffer' to maximize the number of search hits on the screen.
In 'isearch-motion' property of 'scroll-up-command' use 'recenter 0'
for the first line of the screen.
(isearch-beginning-of-buffer)
(isearch-end-of-buffer): Sync logic from 'isearch-allow-motion' part
of isearch-pre-command-hook.  Direct users to isearch-allow-motion
in the docstrings.
(isearch-pre-command-hook): Don't override shifted 'isearch-yank-on-move'
in 'isearch-allow-motion'.

1 files changed, 20 insertions, 9 deletions

diff --git a/lisp/isearch.el b/lisp/isearch.el
index bebc80adb30..3f5e642fd28 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -2003,7 +2003,8 @@ Move point to the beginning of the buffer and search forwards from the top.
 \\<isearch-mode-map>
 With a numeric argument, go to the ARGth absolute occurrence counting from
 the beginning of the buffer.  To find the next relative occurrence forwards,
-type \\[isearch-repeat-forward] with a numeric argument."
+type \\[isearch-repeat-forward] with a numeric argument.
+You might want to use `isearch-allow-motion' instead of this command."
   (interactive "p")
   (if (and arg (< arg 0))
       (isearch-end-of-buffer (abs arg))
@@ -2011,8 +2012,11 @@ type \\[isearch-repeat-forward] with a numeric argument."
     ;; don't forward char in isearch-repeat
     (setq isearch-just-started t)
     (goto-char (point-min))
-    (let ((isearch-repeat-on-direction-change nil))
-      (isearch-repeat 'forward arg))))
+    (let ((current-direction (if isearch-forward 'forward 'backward))
+          (isearch-repeat-on-direction-change nil))
+      (isearch-repeat 'forward arg)
+      (unless (eq current-direction (if isearch-forward 'forward 'backward))
+        (isearch-repeat current-direction)))))
 
 (defun isearch-end-of-buffer (&optional arg)
   "Go to the last occurrence of the current search string.
@@ -2020,14 +2024,18 @@ Move point to the end of the buffer and search backwards from the bottom.
 \\<isearch-mode-map>
 With a numeric argument, go to the ARGth absolute occurrence counting from
 the end of the buffer.  To find the next relative occurrence backwards,
-type \\[isearch-repeat-backward] with a numeric argument."
+type \\[isearch-repeat-backward] with a numeric argument.
+You might want to use `isearch-allow-motion' instead of this command."
   (interactive "p")
   (if (and arg (< arg 0))
       (isearch-beginning-of-buffer (abs arg))
     (setq isearch-just-started t)
     (goto-char (point-max))
-    (let ((isearch-repeat-on-direction-change nil))
-      (isearch-repeat 'backward arg))))
+    (let ((current-direction (if isearch-forward 'forward 'backward))
+          (isearch-repeat-on-direction-change nil))
+      (isearch-repeat 'backward arg)
+      (unless (eq current-direction (if isearch-forward 'forward 'backward))
+        (isearch-repeat current-direction)))))
 
 
 ;;; Toggles for `isearch-regexp-function' and `search-default-mode'.
@@ -2939,9 +2947,9 @@ See also the related option `isearch-allow-motion'."
 (put 'beginning-of-buffer 'isearch-motion
      '((lambda () (goto-char (point-min))) . forward))
 (put 'end-of-buffer 'isearch-motion
-     '((lambda () (goto-char (point-max))) . backward))
+     '((lambda () (goto-char (point-max)) (recenter -1 t)) . backward))
 (put 'scroll-up-command 'isearch-motion
-     '((lambda () (goto-char (window-end)) (recenter 1 t)) . forward))
+     '((lambda () (goto-char (window-end)) (recenter 0 t)) . forward))
 (put 'scroll-down-command 'isearch-motion
      '((lambda () (goto-char (window-start)) (recenter -1 t)) . backward))
 
@@ -3076,7 +3084,10 @@ See more for options in `search-exit-option'."
      ;; Handle motion command functions.
      ((and isearch-allow-motion
            (symbolp this-command)
-           (get this-command 'isearch-motion))
+           (get this-command 'isearch-motion)
+           ;; Don't override `isearch-yank-on-move' used below.
+           (not (and (eq isearch-yank-on-move 'shift)
+                     this-command-keys-shift-translated)))
       (let* ((property (get this-command 'isearch-motion))
              (function (car property))
              (current-direction (if isearch-forward 'forward 'backward))