Add test script for server error cases

util/test_error_cases.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+gameid=${gameid:-devtest}
+minetest=$dir/../bin/minetest
+testspath=$dir/../tests
+conf_server=$testspath/server.conf
+worldpath=$testspath/world
+
+[ -e "$minetest" ] || { echo "executable $minetest missing"; exit 1; }
+
+write_config () {
+	printf '%s\n' >"$conf_server" \
+		helper_mode=error mg_name=singlenode "$@"
+}
+
+run () {
+	timeout 10 "$@"
+	r=$?
+	echo "Exit status: $r"
+	[ $r -eq 124 ] && echo "(timed out)"
+	if [ $r -ne 1 ]; then
+		echo "-> Test failed"
+		exit 1
+	fi
+}
+
+rm -rf "$worldpath"
+mkdir -p "$worldpath/worldmods"
+
+ln -s "$dir/helper_mod" "$worldpath/worldmods/"
+
+args=(--server --config "$conf_server" --world "$worldpath" --gameid $gameid)
+
+# make sure we can tell apart sanitizer and minetest errors
+export ASAN_OPTIONS="exitcode=42"
+export MSAN_OPTIONS="exitcode=42"
+
+# see helper_mod/init.lua for the different types
+for n in $(seq 1 4); do
+	write_config error_type=$n
+	run "$minetest" "${args[@]}"
+	echo "---------------"
+done
+
+echo "All done."
+exit 0