From: Juri Linkov <juri@linkov.net>
Date: Sun, 17 Jul 2022 18:04:29 +0000 (+0300)
Subject: * lisp/minibuffer.el (minibuffer-complete-history): Check for history=t.
X-Git-Tag: emacs-29.0.90~1447^2~878
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=60185819b62e1c06161c93ebdc1dc73e7813604b;p=emacs.git

* lisp/minibuffer.el (minibuffer-complete-history): Check for history=t.

Signal a user error when the history is not a list (bug#56613).
---

diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index 9d2abbd1180..a598fe110f2 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -4409,11 +4409,14 @@ Like `minibuffer-complete' but completes on the history items
 instead of the default completion table."
   (interactive)
   (let ((completions-sort nil)
-        (history (mapcar (lambda (h)
-                           ;; Support e.g. `C-x ESC ESC TAB' as
-                           ;; a replacement of `list-command-history'
-                           (if (consp h) (format "%S" h) h))
-                         (symbol-value minibuffer-history-variable))))
+        (history (symbol-value minibuffer-history-variable)))
+    (if (listp history)
+        ;; Support e.g. `C-x ESC ESC TAB' as
+        ;; a replacement of `list-command-history'
+        (setq history (mapcar (lambda (h)
+                                (if (consp h) (format "%S" h) h))
+                              history))
+      (user-error "No history available"))
     (completion-in-region (minibuffer--completion-prompt-end) (point-max)
                           history nil)))