From 7959a63ce258c90eb3c7947ab3318c5531eb37d9 Mon Sep 17 00:00:00 2001
From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Mon, 18 Dec 2023 23:47:56 -0500
Subject: [PATCH] (eval-expression): Fix bug#67196
* lisp/simple.el (eval-expression--debug): New function.
(eval-expression): Use it together with `handler-bind` instead of
let-binding `debug-on-error`.
---
lisp/simple.el | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)
diff --git a/lisp/simple.el b/lisp/simple.el
index 4f6d2ee12c3..692c0dacefc 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2087,6 +2087,9 @@ of the prefix argument for `eval-expression' and
((= num -1) most-positive-fixnum)
(t eval-expression-print-maximum-character)))))
+(defun eval-expression--debug (err)
+ (funcall debugger 'error err :backtrace-base #'eval-expression--debug))
+
;; We define this, rather than making `eval' interactive,
;; for the sake of completion of names like eval-region, eval-buffer.
(defun eval-expression (exp &optional insert-value no-truncate char-print-limit)
@@ -2120,23 +2123,17 @@ this command arranges for all errors to enter the debugger."
(cons (read--expression "Eval: ")
(eval-expression-get-print-arguments current-prefix-arg)))
- (let (result)
+ (let* (result
+ (runfun
+ (lambda ()
+ (setq result
+ (values--store-value
+ (eval (let ((lexical-binding t)) (macroexpand-all exp))
+ t))))))
(if (null eval-expression-debug-on-error)
- (setq result
- (values--store-value
- (eval (let ((lexical-binding t)) (macroexpand-all exp)) t)))
- (let ((old-value (make-symbol "t")) new-value)
- ;; Bind debug-on-error to something unique so that we can
- ;; detect when evalled code changes it.
- (let ((debug-on-error old-value))
- (setq result
- (values--store-value
- (eval (let ((lexical-binding t)) (macroexpand-all exp)) t)))
- (setq new-value debug-on-error))
- ;; If evalled code has changed the value of debug-on-error,
- ;; propagate that change to the global binding.
- (unless (eq old-value new-value)
- (setq debug-on-error new-value))))
+ (funcall runfun)
+ (handler-bind ((error #'eval-expression--debug))
+ (funcall runfun)))
(let ((print-length (unless no-truncate eval-expression-print-length))
(print-level (unless no-truncate eval-expression-print-level))
--
2.39.5