bug#65379: 29.1.50; isearch started through `isearch-resume' incorrectly moves point after failure

bug#65379: 29.1.50; isearch started through `isearch-resume' incorrectly moves point after failure

[Jens Schmidt via Bug reports for GNU Emacs, the Swiss army knife of text editors]

One of the more arcane features of isearch ... I do not actually
use that, but I modeled one of my personal isearch functions after
`isearch-resume´ and came across this issue.

emacs -Q

M-: (setq isearch-resume-in-command-history t) RET

Then execute:

  f                     ;; self-insert-command
  o                     ;; self-insert-command
  o                     ;; self-insert-command
  b                     ;; self-insert-command
  a                     ;; self-insert-command
  r                     ;; self-insert-command
  b                     ;; self-insert-command
  a                     ;; self-insert-command
  z                     ;; self-insert-command
  <return>              ;; newline
  C-<home>              ;; beginning-of-buffer
  C-s                   ;; isearch-forward
  f                     ;; isearch-printing-char
  o                     ;; isearch-printing-char
  o                     ;; isearch-printing-char
  b                     ;; isearch-printing-char
  a                     ;; isearch-printing-char
  r                     ;; isearch-printing-char
  b                     ;; isearch-printing-char
  a                     ;; isearch-printing-char
  z                     ;; isearch-printing-char
  <return>              ;; isearch-exit
  C-<home>              ;; beginning-of-buffer
  C-x <escape> <escape> ;; repeat-complex-command
  <return>              ;; read--expression-try-read
  C-s                   ;; isearch-repeat-forward

=> point jumps to bob and the complete buffer gets highlighted on the
   search failure after the `C-s'

I'm not an isearch expert, but I think the remedy should be to add a
call to `isearch-push-state' before the call to `isearch-update' in
function `isearch-resume':

diff --git a/lisp/isearch.el b/lisp/isearch.el
index 3d2bbda4975..14f335f4cea 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -4640,6 +4640,7 @@ isearch-resume
 	isearch-message message
 	isearch-case-fold-search case-fold)
   (isearch-search)
+  (isearch-push-state)
   (isearch-update))
 
At least that helps preventing the incorrect behavior, and most other
calls to `isearch-update' have a preceeding call to `isearch-push-state'
in isearch.el.  But that doesn't mean anything, of course, so somebody
else should review that.

bug#65379: 29.1.50; isearch started through `isearch-resume' incorrectly moves point after failure

[Juri Linkov]

close 65379 30.0.50
thanks

> One of the more arcane features of isearch ... I do not actually
> use that, but I modeled one of my personal isearch functions after
> `isearch-resume´ and came across this issue.

Thanks for the bug report.  I don't use `isearch-resume',
so never noticed this bug.

> I'm not an isearch expert, but I think the remedy should be to add a
> call to `isearch-push-state' before the call to `isearch-update' in
> function `isearch-resume':
>
> diff --git a/lisp/isearch.el b/lisp/isearch.el
> index 3d2bbda4975..14f335f4cea 100644
> --- a/lisp/isearch.el
> +++ b/lisp/isearch.el
> @@ -4640,6 +4640,7 @@ isearch-resume
>  	isearch-message message
>  	isearch-case-fold-search case-fold)
>    (isearch-search)
> +  (isearch-push-state)
>    (isearch-update))
>
> At least that helps preventing the incorrect behavior, and most other
> calls to `isearch-update' have a preceeding call to `isearch-push-state'
> in isearch.el.  But that doesn't mean anything, of course, so somebody
> else should review that.

You are absolutely right.  This is the correct way to fix it.
Now pushed to master.  Thanks for the patch.