From 6f65e6a60449f1e4884987ee3d56199a46fdb82c Mon Sep 17 00:00:00 2001
From: Daniel Mendler <mail@daniel-mendler.de>
Date: Tue, 1 Aug 2023 17:45:17 +0200
Subject: compat-29: Add bidi-string-strip-control-characters

---
 NEWS.org        | 1 +
 compat-29.el    | 8 ++++++++
 compat-tests.el | 6 ++++++
 compat.texi     | 7 ++++++-
 4 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/NEWS.org b/NEWS.org
index 7e41ec1..edf39af 100644
--- a/NEWS.org
+++ b/NEWS.org
@@ -4,6 +4,7 @@
 
 * Development
 
+- compat-29: Add function =bidi-string-strip-control-characters=.
 - compat-29: Add function =char-uppercase-p=.
 - compat-29: Add function =window-configuration-equal-p=.
 
diff --git a/compat-29.el b/compat-29.el
index 3db94c9..28e9105 100644
--- a/compat-29.el
+++ b/compat-29.el
@@ -508,6 +508,14 @@ thus overriding the value of the TIMEOUT argument to that function.")
     (when message (message "%s" message))
     exitfun))
 
+;;;; Defined in characters.el
+
+(compat-defun bidi-string-strip-control-characters (string) ;; <compat-tests:bidi-string-strip-control-characters>
+  "Strip bidi control characters from STRING and return the result."
+  (apply #'string (seq-filter (lambda (char)
+                                (not (memq char bidi-control-characters)))
+                              string)))
+
 ;;;; Defined in simple.el
 
 (compat-defun char-uppercase-p (char) ;; <compat-tests:char-uppercase-p>
diff --git a/compat-tests.el b/compat-tests.el
index 02fa536..19c13ed 100644
--- a/compat-tests.el
+++ b/compat-tests.el
@@ -1843,6 +1843,12 @@
   (dolist (c (list ?a ?b ?α ?β))
     (should-not (char-uppercase-p c))))
 
+(ert-deftest compat-bidi-string-strip-control-characters ()
+  (should-equal (bidi-string-strip-control-characters (apply #'string bidi-control-characters)) "")
+  (should-equal (bidi-string-strip-control-characters "\x202e") "")
+  (should-equal (bidi-string-strip-control-characters "abc") "abc")
+  (should-equal (bidi-string-strip-control-characters "x\x202ey\x202ez") "xyz"))
+
 (ert-deftest compat-string-split ()
   (should-equal '("a" "b" "c") (split-string "a b c"))
   (should-equal '("a" "b" "c") (string-split "a b c")))
diff --git a/compat.texi b/compat.texi
index 1c9e278..4ec60a9 100644
--- a/compat.texi
+++ b/compat.texi
@@ -2613,6 +2613,11 @@ The name follows the convention of other string functions.
 @xref{Creating Strings,,,elisp}.
 @end defun
 
+@c based on lisp/international/characters.el
+@defun bidi-string-strip-control-characters string
+Strip bidi control characters from @var{string} and return the result.
+@end defun
+
 @c copied from lispref/buffers.texi
 @defun buffer-match-p condition buffer-or-name &optional arg
 This function checks if a buffer designated by @code{buffer-or-name}
@@ -2914,7 +2919,7 @@ local map.
 @xref{Key Binding Commands,,,elisp}.
 @end defun
 
-@c based on from lisp/keymap.el
+@c based on lisp/keymap.el
 @defun keymap-substitute keymap olddef newdef &optional oldmap prefix
 Replace @var{olddef} with @var{newdef} for any keys in @var{keymap}
 now defined as @var{olddef}.  In other words, @var{olddef} is replaced
-- 
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