bug#37073: 26.2.90; query-replace-regexp undo feature missing quote the regexps

[Tino Calancha <tino.calancha@gmail.com>]

Tags: patch

That causes the undo feature to fail if the replacement contains special characters.

emacs -Q

C-x b *foo* RET
M-: (insert "theorem 1\ntheorem 2\ntheorem 3") RET
M-<
M-C-%
theorem \([0-9]+\) RET
\,(format "theorem \\ref{theo_%s}" \1) RET
SPC
SPC
u
q

;; Buffer *foo* now contains:
theorem 1ref{theo_1}
theorem 2ref{theo_2}
theorem 3

;; Expected:
theorem 1
theorem 2
theorem 3


--8<-----------------------------cut here---------------start------------->8---
commit 9f9c56cfa99b1e6fe296ec591ab335521e185e55
Author: Tino Calancha <tino.calancha@gmail.com>
Date:   Sun Aug 18 15:57:59 2019 +0200

    Fix query-replace-regexp undo feature
    
    * lisp/replace.el (perform-replace): Quote regexp (Bug#37073).
    * test/lisp/replace-tests.el (query-replace-undo-bug37073): Add test

diff --git a/lisp/replace.el b/lisp/replace.el
index 08feb8eae7..fb703abd92 100644
--- a/lisp/replace.el
+++ b/lisp/replace.el
@@ -2614,7 +2614,7 @@ perform-replace
                                    (setq real-match-data
                                          (save-excursion
                                            (goto-char (match-beginning 0))
-                                           (looking-at search-string)
+                                           (looking-at (regexp-quote search-string)) ; Bug#37073
                                            (match-data t (nth 2 elt)))
                                          noedit
                                          (replace-match-maybe-edit
diff --git a/test/lisp/replace-tests.el b/test/lisp/replace-tests.el
index cd30633e37..f96bd9cf05 100644
--- a/test/lisp/replace-tests.el
+++ b/test/lisp/replace-tests.el
@@ -454,5 +454,15 @@ replace-tests--query-replace-undo
       input "a" "B" ((?\s . (1 2 3)) (?E . (4)) (?U . (5))) ?q
       (string= input (buffer-string))))))
 
+(ert-deftest query-replace-undo-bug37073 ()
+  "Test for https://debbugs.gnu.org/37073 ."
+  (let ((input "theorem 1\ntheorem 2\ntheorem 3"))
+    (should
+     (replace-tests-with-undo
+      input "theorem \\([0-9]+\\)"
+      "theorem \\\\ref{theo_\\1}"
+      ((?\s . (1 2)) (?U . (3)))
+      ?q
+      (string= input (buffer-string))))))
 
 ;;; replace-tests.el ends here

--8<-----------------------------cut here---------------end--------------->8---

In GNU Emacs 26.2.90 (build 19, x86_64-pc-linux-gnu, GTK+ Version 3.24.5)
 of 2019-08-18 built
Repository revision: 3f00db7ca6d40312651a302842561e7fb168ee99