# create test objects
dat <- mice::nhanes
pred <- mice::quickpred(dat)
imp <- mice::mice(dat, printFlag = FALSE)

# tests
test_that("plot_pred creates ggplot object", {
  expect_s3_class(plot_pred(pred), "ggplot")
  expect_s3_class(plot_pred(
    pred,
    method = c("pmm"),
    label = FALSE,
    square = FALSE,
    rotate = TRUE
  ),
  "ggplot")
  expect_s3_class(plot_pred(pred, vrb = c("age", "bmi")), "ggplot")
  expect_s3_class(plot_pred(pred, vrb = c(age, bmi)), "ggplot")
  expect_s3_class(plot_pred(rbind(
    cbind(pred, "with space" = 0), "with space" = 0
  )), "ggplot")
  expect_s3_class(plot_pred(imp, vrb = c("age", "bmi")), "ggplot")
})

test_that("plot_pred with incorrect argument(s)", {
  expect_error(plot_pred(dat))
})