From d928682b389f09a66afaa65de382da2a7426d9a6 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Fri, 25 Sep 2026 14:45:18 +0100
Subject: [PATCH] 5438 test.

---
 regress/socket-path.sh | 57 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 regress/socket-path.sh

diff --git a/regress/socket-path.sh b/regress/socket-path.sh
new file mode 100644
index 000000000..eb3b2dbfe
--- /dev/null
+++ b/regress/socket-path.sh
@@ -0,0 +1,57 @@
+#!/bin/sh
+
+# The socket directory must be an existing absolute path without "..". An
+# empty $TMUX_TMPDIR is skipped.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+unset TMUX TMUX_TMPDIR
+
+TMP=$(mktemp -d)
+TMP=$(cd "$TMP" && pwd -P)
+L="testSP$$"
+DEFAULT="$(cd /tmp && pwd -P)/tmux-$(id -u)/$L"
+
+cleanup()
+{
+	"$TEST_TMUX" -S "$DEFAULT" kill-server 2>/dev/null
+	"$TEST_TMUX" -S "$TMP/tmux-$(id -u)/$L" kill-server 2>/dev/null
+	rm -rf "$TMP" "$DEFAULT" "$DEFAULT.lock"
+}
+trap cleanup 0 1 15
+
+# check_path expected env...
+check_path()
+{
+	expected=$1; shift
+	env "$@" "$TEST_TMUX" -L"$L" -f/dev/null new -d 'sleep 60' || exit 1
+	actual=$(env "$@" "$TEST_TMUX" -L"$L" display -p '#{socket_path}')
+	env "$@" "$TEST_TMUX" -L"$L" kill-server
+	[ "$actual" = "$expected" ] || exit 1
+}
+
+# check_error expected env...
+check_error()
+{
+	expected=$1; shift
+	if actual=$(env "$@" "$TEST_TMUX" -L"$L" -f/dev/null new -d \
+	    'sleep 60' 2>&1); then
+		env "$@" "$TEST_TMUX" -L"$L" kill-server
+		exit 1
+	fi
+	[ "$actual" = "$expected" ] || exit 1
+}
+
+check_path "$DEFAULT" TMUX_TMPDIR=
+check_path "$TMP/tmux-$(id -u)/$L" TMUX_TMPDIR="$TMP"
+
+check_error "socket directory tmp is not an absolute path" TMUX_TMPDIR=tmp
+check_error "couldn't resolve socket directory $TMP/missing (No such file or directory)" \
+    TMUX_TMPDIR="$TMP/missing"
+check_error "socket directory $TMP/.. contains .." TMUX_TMPDIR="$TMP/.."
+check_error "socket directory /../tmp contains .." TMUX_TMPDIR=/../tmp
+check_error "socket directory $TMP/../.. contains .." TMUX_TMPDIR="$TMP/../.."
+
+exit 0