test_that("sparsediscrim::qda_diag fit and prediction", {
  skip_if_not_installed("sparsediscrim")
  skip_if_not_installed("mlbench")

  spd_fit <- sparsediscrim::qda_diag(
    glass_tr |> dplyr::select(RI, Na, Mg),
    glass_tr$Type
  )
  spd_pred <-
    predict(
      spd_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "class"
    )
  spd_prob <-
    predict(
      spd_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "prob"
    )
  expect_no_error(
    d_fit <-
      discrim_quad(regularization_method = "diagonal") |>
      set_engine("sparsediscrim") |>
      fit(Type ~ ., data = glass_tr |> dplyr::select(RI, Na, Mg, Type))
  )
  expect_no_error(
    d_pred <- predict(
      d_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "class"
    )
  )
  expect_no_error(
    d_prob <- predict(
      d_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "prob"
    )
  )
  expect_equal(
    spd_pred,
    d_pred$.pred_class
  )

  expect_equal(
    spd_prob |> tibble::as_tibble(),
    d_prob,
    ignore_attr = TRUE
  )
})


# ------------------------------------------------------------------------------

test_that("sparsediscrim::qda_shrink_mean fit and prediction", {
  skip_if_not_installed("sparsediscrim")
  skip_if_not_installed("mlbench")

  spd_fit <- sparsediscrim::qda_shrink_mean(
    glass_tr |> dplyr::select(RI, Na, Mg),
    glass_tr$Type
  )
  spd_pred <-
    predict(
      spd_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "class"
    )
  spd_prob <-
    predict(
      spd_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "prob"
    )
  expect_no_error(
    d_fit <-
      discrim_quad(regularization_method = "shrink_mean") |>
      set_engine("sparsediscrim") |>
      fit(Type ~ ., data = glass_tr |> dplyr::select(RI, Na, Mg, Type))
  )
  expect_no_error(
    d_pred <- predict(
      d_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "class"
    )
  )
  expect_no_error(
    d_prob <- predict(
      d_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "prob"
    )
  )
  expect_equal(
    spd_pred,
    d_pred$.pred_class
  )

  expect_equal(
    spd_prob |> tibble::as_tibble(),
    d_prob,
    ignore_attr = TRUE
  )
})

# ------------------------------------------------------------------------------

test_that("sparsediscrim::qda_shrink_cov fit and prediction", {
  skip_if_not_installed("sparsediscrim")
  skip_if_not_installed("mlbench")

  spd_fit <- sparsediscrim::qda_shrink_cov(
    glass_tr |> dplyr::select(RI, Na, Mg),
    glass_tr$Type
  )
  spd_pred <-
    predict(
      spd_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "class"
    )
  spd_prob <-
    predict(
      spd_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "prob"
    )
  expect_no_error(
    d_fit <-
      discrim_quad(regularization_method = "shrink_cov") |>
      set_engine("sparsediscrim") |>
      fit(Type ~ ., data = glass_tr |> dplyr::select(RI, Na, Mg, Type))
  )
  expect_no_error(
    d_pred <- predict(
      d_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "class"
    )
  )
  expect_no_error(
    d_prob <- predict(
      d_fit,
      glass_te |> dplyr::select(RI, Na, Mg),
      type = "prob"
    )
  )
  expect_equal(
    spd_pred,
    d_pred$.pred_class
  )

  expect_equal(
    spd_prob |> tibble::as_tibble(),
    d_prob,
    ignore_attr = TRUE
  )
})