From 871e1a8ab2bb1f46076efdb634719af325762ab7 Mon Sep 17 00:00:00 2001
From: Michael Mikonos <127171689+mknos@users.noreply.github.com>
Date: Fri, 29 Nov 2024 13:17:38 +0800
Subject: [PATCH] ed: prevent trailing '/' when setting filename

* The usage "f abc/" is technically invalid because it would point to a directory
* Subsequent "e" or "w" commands fail because ed does not operate on directories
* GNU ed 1.20 added validation to prevent this usage; add it here because it would flag bad user input slightly earlier
---
 bin/ed | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/bin/ed b/bin/ed
index 4cd04e26..48d8ff18 100755
--- a/bin/ed
+++ b/bin/ed
@@ -579,9 +579,8 @@ sub edFilename {
         return E_ADDREXT;
     }
     if (defined($args[0])) {
-        if ($args[0] =~ m/\A\!/) {
-            return E_FNAME;
-        }
+        return E_FNAME if $args[0] =~ m/\A\!/;
+        return E_FNAME if $args[0] =~ m/\/\Z/;
         $RememberedFilename = $args[0];
     }
     if (defined($RememberedFilename)) {