[lang-ref] カラでないときに代替値を出す ( bash )

@test "returns value if not empty" {

	# ex: masking
	password=
	log="password:${password:+**********}"
	[ "$log" = "password:" ]

	password="asfdsfasa"
	log="password:${password:+**********}"
	[ "$log" = "password:**********" ]


}