test_that("bcat_plt_diag returns patchwork object", {
  m <- lm(mpg ~ wt + hp, data = mtcars)
  p <- bcat_plt_diag(m, tests = FALSE)
  expect_true(inherits(p, "patchwork"))
})

test_that("bcat_plt_diag works with which parameter", {
  m <- lm(mpg ~ wt + hp, data = mtcars)
  p <- bcat_plt_diag(m, which = c(1, 2), tests = FALSE)
  expect_true(inherits(p, "patchwork") || inherits(p, "ggplot"))
})