Add some tests.

regress/cmd-invoke-failure-scope.sh

@@ -0,0 +1,72 @@
+#!/bin/sh
+
+# Command failure scope.
+#
+# Failure scope is the active sequence (CMD_PARSE_SEQUENCE): commands joined by
+# ';' share one scope, so a failure skips the rest of that sequence; commands on
+# separate lines are independent sequences and are not skipped. After a failed
+# inner brace the enclosing sequence still resumes.
+#
+# Each case below creates windows around a deliberately invalid command and the
+# resulting window list shows exactly which commands ran.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -Ltest -f/dev/null"
+$TMUX kill-server 2>/dev/null
+
+TMP=$(mktemp)
+CONF=$(mktemp)
+trap "rm -f $TMP $CONF" 0 1 15
+
+# kill-server is asynchronous, so wait for the old server to actually exit
+# before starting a fresh one (otherwise the next start races a dying server).
+fresh_server() {
+	$TMUX kill-server 2>/dev/null
+	i=0
+	while $TMUX list-sessions >/dev/null 2>&1; do
+		sleep 0.05
+		i=$((i + 1))
+		[ $i -gt 100 ] && break
+	done
+	$TMUX -f/dev/null start \; new-session -d -swork -nbase || exit 1
+}
+
+# $1 label, $2 config body, $3 expected comma-separated window list.
+run() {
+	fresh_server
+	printf '%s\n' "$2" >$CONF
+	$TMUX source-file $CONF >/dev/null 2>&1
+	got=$($TMUX list-windows -t work -F '#{window_name}' | tr '\n' ',')
+	if [ "$got" != "$3" ]; then
+		echo "$1: got [$got] expected [$3]" >&2
+		exit 1
+	fi
+}
+
+# ';' sequence in a brace body: A runs, the bad command skips B (same sequence),
+# the outer sequence resumes so C runs.
+run "semicolon body" 'if-shell true { new-window -dn A ; nonexistent_cmd ; new-window -dn B }
+new-window -dn C' 'base,A,C,'
+
+# Newlines are independent sequences: the bad command skips only itself, so both
+# B and C still run.
+run "newline body" 'if-shell true {
+  new-window -dn A
+  nonexistent_cmd
+  new-window -dn B
+}
+new-window -dn C' 'base,A,B,C,'
+
+# Top-level ';' sequence: failure skips the rest of the line.
+run "top-level semicolon" 'new-window -dn A ; nonexistent_cmd ; new-window -dn B' 'base,A,'
+
+# Top-level newlines: independent, both run.
+run "top-level newline" 'new-window -dn A
+nonexistent_cmd
+new-window -dn B' 'base,A,B,'
+
+$TMUX kill-server 2>/dev/null
+exit 0