test_that("Master fit function unifies MLE, Bootstrap, and Bayes correctly", {
  data("burr_data", package = "BivTrigBurr")

  set.seed(123)
  fit_all <- fit_sps_bxii(x = burr_data$x, y = burr_data$y,
                          methods = c("mle", "boot", "bayes"),
                          B = 10, n_iter = 200, burn_in = 50)

  expect_s3_class(fit_all, "sps_bxii_fit")
  expect_false(is.null(fit_all$mle))
  expect_false(is.null(fit_all$boot))
  expect_false(is.null(fit_all$bayes))
  expect_false(is.null(fit_all$summary_table))
  expect_false(is.null(fit_all$criteria))

  expect_output(print(fit_all))
})