branch: externals/vertico
commit 95d0d4c9aa0d13e4333cec0fdfdf19487e282a28
Author: Daniel Mendler <m...@daniel-mendler.de>
Commit: Daniel Mendler <m...@daniel-mendler.de>
Guard Vertico hooks to automatically show stack traces
---
CHANGELOG.org | 5 +++++
README.org | 20 +++-----------------
vertico.el | 35 +++++++++++++++++++++++++++++------
3 files changed, 37 insertions(+), 23 deletions(-)
diff --git a/CHANGELOG.org b/CHANGELOG.org
index 8d15a5967c..4d6e1a23de 100644
--- a/CHANGELOG.org
+++ b/CHANGELOG.org
@@ -2,6 +2,11 @@
#+author: Daniel Mendler
#+language: en
+* Development
+
+- Guard Vertico hooks to automatically print stack traces in order to ease
+ debugging.
+
* Version 2.1 (2025-04-19)
- =vertico-flat-format=: Customizable =:spacer= string.
diff --git a/README.org b/README.org
index 9e8381e57b..2fa61ce9ed 100644
--- a/README.org
+++ b/README.org
@@ -502,23 +502,9 @@ assignment to the FSF.
* Debugging Vertico
-When you observe an error in the =vertico--exhibit= post command hook, you
should
-install an advice to enforce debugging. This allows you to obtain a stack trace
-in order to narrow down the location of the error. The reason is that post
-command hooks are automatically disabled (and not debugged) by Emacs. Otherwise
-Emacs would become unusable, given that the hooks are executed after every
-command.
-
-#+begin_src emacs-lisp
-(setq debug-on-error t)
-
-(defun force-debug (func &rest args)
- (condition-case e
- (apply func args)
- ((debug error) (signal (car e) (cdr e)))))
-
-(advice-add #'vertico--exhibit :around #'force-debug)
-#+end_src
+Vertico will automatically print a stack trace to the =*Messages*= buffer when
an
+error is detected. The stack trace allows you to narrow down the exact code
+location which caused the error.
* Problematic completion commands
diff --git a/vertico.el b/vertico.el
index efab3dca23..6c97e9a3d4 100644
--- a/vertico.el
+++ b/vertico.el
@@ -463,14 +463,37 @@ The value should lie between 0 and vertico-count/2."
(put-text-property beg next 'face (remq face (ensure-list val)) obj))
(setq beg next))))
+(defun vertico--debug (&rest _)
+ "Debugger used by `vertico--guard'."
+ (require 'backtrace)
+ (declare-function backtrace-to-string "backtrace")
+ (declare-function backtrace-get-frames "backtrace")
+ (let ((inhibit-message t))
+ (message "Vertico detected an error:\n%s"
+ (backtrace-to-string (backtrace-get-frames #'vertico--debug))))
+ (let (message-log-max)
+ (message "%s %s"
+ (propertize "Vertico detected an error:" 'face 'error)
+ (substitute-command-keys "Press \\[view-echo-area-messages] to
see the stack trace")))
+ nil)
+
+(defmacro vertico--guard (&rest body)
+ "Guard BODY showing a stack trace on error."
+ `(condition-case nil
+ (let ((debug-on-error t)
+ (debugger #'vertico--debug))
+ ,@body)
+ ((debug error) nil)))
+
(defun vertico--exhibit ()
"Exhibit completion UI."
- (let ((buffer-undo-list t)) ;; Overlays affect point position and undo list!
- (vertico--update 'interruptible)
- (vertico--prompt-selection)
- (vertico--display-count)
- (vertico--display-candidates (vertico--arrange-candidates))
- (vertico--resize)))
+ (vertico--guard
+ (let ((buffer-undo-list t)) ;; Overlays affect point position and undo list!
+ (vertico--update 'interruptible)
+ (vertico--prompt-selection)
+ (vertico--display-count)
+ (vertico--display-candidates (vertico--arrange-candidates))
+ (vertico--resize))))
(defun vertico--goto (index)
"Go to candidate with INDEX."
