From 80713070f41e2cbfec1fa9db923b2a07032f061d Mon Sep 17 00:00:00 2001
From: Gerard Vermeulen <gerard.vermeulen@posteo.net>
Date: Fri, 14 Jun 2024 11:10:41 +0200
Subject: [PATCH] Tweak the `savehist-mode' setup

---
 README.org | 30 ++++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/README.org b/README.org
index 428c943..116ed54 100644
--- a/README.org
+++ b/README.org
@@ -228,6 +228,7 @@ of [[info:emacs#Saving Customizations][saving customizations (info)]].
  recentf-max-saved-items 100
  recentf-mode t
  save-place-mode t
+ savehist-mode t
  scroll-bar-mode nil
  tab-always-indent 'complete
  tool-bar-mode nil
@@ -1353,10 +1354,11 @@ completion in any buffer.
 :END:
 
 Listing [[lst:enable-vertico-mode]] configures and enables =savehist-mode= and
-enables =vertico-mode=.  The documentation src_emacs-lisp{(describe-function
-'savehist-mode)} why it is best to turn on =savehist-mode= in the Emacs init
-file.  BUG: Adding ~eww-history~, ~register-alist~, ~regexp-search-string~, or
-~search-string~ to ~savehist-additional-variables~ fails to save the relevant
+enables =vertico-mode=.  The src_emacs-lisp{(describe-function 'savehist-mode)}
+documentation explains why it is best to turn on =savehist-mode= in the
+=user-init-file=.  Listing [[lst:prune-file-name-history]] allows to prune
+non-existing files from the file name history.  BUG: Adding ~eww-history~ or
+~register-alist~ to ~savehist-additional-variables~ fails to save the relevant
 histories.
 
 #+caption[Enable =savehist-mode= and =vertico-mode=]:
@@ -1364,8 +1366,8 @@ histories.
 #+name: lst:enable-vertico-mode
 #+begin_src emacs-lisp -n :results silent
 (with-eval-after-load 'savehist
-  (setopt savehist-additional-variables '(kill-ring search-ring))
-  (savehist-mode +1))
+  (setopt savehist-additional-variables
+          '(command-history kill-ring regexp-search-ring search-ring)))
 (when (and (ensure-package-installation 'vertico)
            (fboundp 'vertico-directory-delete-char)
            (fboundp 'vertico-directory-delete-word)
@@ -1379,6 +1381,22 @@ histories.
     (keymap-set vertico-map "RET" #'vertico-directory-enter)))
 #+end_src
 
+#+caption[Prune non-existing files from =file-name-history=]:
+#+caption: Prune non-existing files from =file-name-history=.
+#+name: lst:prune-file-name-history
+#+begin_src emacs-lisp -n :results silent
+(defun prune-file-name-history ()
+  "Prune non-existing files from `file-name-history'."
+  (interactive)
+  (let ((old (length file-name-history)) ok)
+    (dolist (name file-name-history)
+      (when (file-exists-p name)
+        (push name ok)))
+    (setq file-name-history (nreverse ok))
+    (message "Pruned `file-name-history' from `%S' to `%S' files"
+             old (length file-name-history))))
+#+end_src
+
 #+attr_latex: :booktabs yes :float table
 #+caption[Vertico key map bindings]:
 #+caption: Vertico key map bindings.