From e55c693d1a1e68e57c1e77cd56e65d227c173a9f Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 5 Oct 2026 14:46:14 +0100
Subject: [PATCH] Test for 5688.

---
 regress/cmd-parse-condition.sh | 75 ++++++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 regress/cmd-parse-condition.sh

diff --git a/regress/cmd-parse-condition.sh b/regress/cmd-parse-condition.sh
new file mode 100644
index 000000000..c5487cc2f
--- /dev/null
+++ b/regress/cmd-parse-condition.sh
@@ -0,0 +1,75 @@
+#!/bin/sh
+
+# Assignments and commands must use the first matching conditional branch.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+CONF=$(mktemp)
+trap '$TMUX kill-server 2>/dev/null; rm -f "$CONF"' 0
+trap 'exit 1' 1 2 15
+$TMUX new-session -d || exit 1
+
+branch()
+{
+	printf '%%%s %s%s' "$1" "$2" "$sep"
+	printf '%sPARSE_BRANCH=%s%sset -g @branch %s%s' \
+	    "$prefix" "$3" "$sep" "$3" "$sep"
+}
+
+# Cover no, one and two elif branches, with and without else, all condition
+# values, and nesting inside both an active and an inactive outer branch.
+for mode in normal hidden inline; do
+	prefix=
+	sep='
+'
+	[ "$mode" = hidden ] && prefix='%hidden '
+	[ "$mode" = inline ] && sep=' '
+	for elifs in 0 1 2; do
+		bits=0
+		while [ "$bits" -lt "$((1 << (elifs + 1)))" ]; do
+			for otherwise in 0 1; do
+				for outer in 0 1; do
+					expected=unchanged
+					{
+						printf '%s\n' 'PARSE_BRANCH=unchanged' \
+						    'set -g @branch unchanged'
+						printf '%%if %s\n' "$outer"
+						n=0
+						while [ "$n" -le "$elifs" ]; do
+							condition=$(((bits >> n) & 1))
+							directive=elif
+							[ "$n" -eq 0 ] && directive=if
+							branch "$directive" "$condition" "$n"
+							if [ "$condition" -eq 1 ] &&
+							    [ "$expected" = unchanged ]; then
+								expected=$n
+							fi
+							n=$((n + 1))
+						done
+						if [ "$otherwise" -eq 1 ]; then
+							branch else '' else
+							[ "$expected" = unchanged ] && expected=else
+						fi
+						printf '%s\n' '%endif' '%endif' \
+						    'set -g @value "$PARSE_BRANCH"'
+					} >"$CONF"
+					[ "$outer" -eq 0 ] && expected=unchanged
+					$TMUX source-file "$CONF" || exit 1
+					out=$($TMUX display-message -p '#{@value}:#{@branch}')
+					if [ "$out" != "$expected:$expected" ]; then
+						echo "$mode, $elifs elifs, bits=$bits, else=$otherwise, outer=$outer"
+						echo "Expected $expected:$expected, got $out"
+						cat "$CONF"
+						exit 1
+					fi
+				done
+			done
+			bits=$((bits + 1))
+		done
+	done
+done
+
+exit 0