context("gppm-plotlong")
test_that("simple", {
  thePlot <- plot(demoLGCM)
  expect_identical(class(thePlot), c("gg", "ggplot"))
})

test_that("select all arguments", {
  thePlot <- plot(demoLGCM, c(1, 2, 3), "t", "ID", "y")
  expect_identical(class(thePlot), c("gg", "ggplot"))
})