test_that("model_parameters.rlm", {
  skip_if_not_installed("MASS")

  model <- MASS::rlm(formula = mpg ~ am * cyl, data = mtcars)
  s <- summary(model)
  params <- model_parameters(model)
  expect_equal(params$SE, as.vector(coef(s)[, 2]), tolerance = 1e-3)
  expect_equal(params$Coefficient, as.vector(coef(s)[, 1]), tolerance = 1e-3)
  expect_equal(params$t, as.vector(coef(s)[, 3]), tolerance = 1e-3)
  expect_equal(params$df_error, c(28, 28, 28, 28), tolerance = 1e-3)
  expect_equal(
    colnames(params),
    c("Parameter", "Coefficient", "SE", "CI", "CI_low", "CI_high", "t", "df_error", "p")
  )
})