Would be better we also add testUsingScript(). something like this (we already have router.groovy inside tests):

stream().create("f", "queue:foo > transform --expression=payload+'-foo' | %s", fileSink);
		stream().create("b", "queue:bar > transform --expression=payload+'-bar' | %s", fileSink);
		stream().create("script-test", "%s | router --script='org/springframework/xd/dirt/stream/router.groovy'",
				httpSource);