test_that("ggcosinor makes a ggplot", {
	data("twins")
	scos <- cosinor(rDYX ~ hour, twins, 24)
	mcos <- cosinor(rDYX ~ hour, twins, c(24, 12))
	pcos <- expect_message(cosinor(rDYX ~ hour, twins, 24, "patid"))
	g <- expect_message(expect_warning(ggcosinor(mcos)))
	expect_s3_class(g, "ggplot")

	gg <- expect_message(expect_warning(ggcosinor(list(scos, mcos))))
	expect_s3_class(gg, "ggplot")
})