Subject: 29.0.60; Fix regexp pattern case in hi-lock

From: Juri Linkov <[email-masked]>
Date: Wed, 21 Dec 2022 19:29:11 +0200

Version: 29.0.60
Tags: patch

0. emacs -Q
1. Type [ M-< C-s [ M-s h r RET M-s h u

Debugger entered--Lisp error: (invalid-regexp "Unmatched [ or [^")
  hi-lock--regexps-at-point()
  command-execute(unhighlight-regexp)

Here is a patch to fix this error:

diff --git a/lisp/hi-lock.el b/lisp/hi-lock.el
index a45e74eca26..bc631747e6d 100644
--- a/lisp/hi-lock.el
+++ b/lisp/hi-lock.el
@@ -569,24 +569,29 @@ hi-lock--regexps-at-point
       (when (and face-before face-after (not (eq face-before face-after)))
         (setq face-before nil))
       (when (or face-after face-before)
-        (let* ((hi-text
-                (buffer-substring-no-properties
-                 (if face-before
-                     (or (previous-single-property-change (point) 'face)
-                         (point-min))
-                   (point))
-                 (if face-after
-                     (or (next-single-property-change (point) 'face)
-                         (point-max))
-                   (point)))))
+        (let* ((beg (if face-before
+                        (or (previous-single-property-change (point) 'face)
+                            (point-min))
+                      (point)))
+               (end (if face-after
+                        (or (next-single-property-change (point) 'face)
+                            (point-max))
+                      (point))))
           ;; Compute hi-lock patterns that match the
           ;; highlighted text at point.  Use this later in
           ;; during completing-read.
           (dolist (hi-lock-pattern hi-lock-interactive-patterns)
-            (let ((regexp (or (car (rassq hi-lock-pattern hi-lock-interactive-lighters))
-                              (car hi-lock-pattern))))
-              (if (string-match regexp hi-text)
-                  (push regexp regexps)))))))
+            (let ((pattern (or (rassq hi-lock-pattern hi-lock-interactive-lighters)
+                               (car hi-lock-pattern))))
+              (cond
+               ((stringp pattern)
+                (when (string-match pattern (buffer-substring-no-properties beg end))
+                  (push pattern regexps)))
+               ((functionp (cadr pattern))
+                (save-excursion
+                  (goto-char beg)
+                  (when (funcall (cadr pattern) end)
+                    (push (car pattern) regexps))))))))))
     regexps))
 
 (defvar-local hi-lock--unused-faces nil