diff --git a/tests/testthat/_snaps/grf.md b/tests/testthat/_snaps/grf.md
new file mode 100644
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+++ b/tests/testthat/_snaps/grf.md
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+# grf classification
+
+    Code
+      translate(set_mode(set_engine(rand_forest(mtry = 100, trees = 1, min_n = 1000),
+      "grf"), "classification"))
+    Output
+      Random Forest Model Specification (classification)
+      
+      Main Arguments:
+        mtry = 100
+        trees = 1
+        min_n = 1000
+      
+      Computational engine: grf 
+      
+      Model fit template:
+      grf::probability_forest(X = missing_arg(), Y = missing_arg(), 
+          weights = missing_arg(), mtry = min_cols(~100, x), num.trees = 1, 
+          min.node.size = min_rows(~1000, x), num.threads = 1)
+
+---
+
+    ! 100 columns were requested but there were 29 predictors in the data.
+    i 29 predictors will be used.
+
+# grf regression
+
+    Code
+      translate(set_mode(set_engine(rand_forest(mtry = 100, trees = 1, min_n = 1000),
+      "grf"), "regression"))
+    Output
+      Random Forest Model Specification (regression)
+      
+      Main Arguments:
+        mtry = 100
+        trees = 1
+        min_n = 1000
+      
+      Computational engine: grf 
+      
+      Model fit template:
+      grf::regression_forest(X = missing_arg(), Y = missing_arg(), 
+          weights = missing_arg(), mtry = min_cols(~100, x), num.trees = 1, 
+          min.node.size = min_rows(~1000, x), num.threads = 1)
+
+# grf quantile regression
+
+    Code
+      translate(set_mode(set_engine(rand_forest(mtry = 100, trees = 1, min_n = 1000),
+      "grf"), "quantile regression", quantile_levels = (1:3) / 4))
+    Output
+      Random Forest Model Specification (quantile regression)
+      
+      Main Arguments:
+        mtry = 100
+        trees = 1
+        min_n = 1000
+      
+      Computational engine: grf 
+      
+      Model fit template:
+      grf::quantile_forest(X = missing_arg(), Y = missing_arg(), mtry = min_cols(~100, 
+          x), num.trees = 1, min.node.size = min_rows(~1000, x), num.threads = 1, 
+          quantiles = quantile_levels)
+    Message
+      Quantile levels: 0.25, 0.5, and 0.75.
+
diff --git a/tests/testthat/test-grf.R b/tests/testthat/test-grf.R
new file mode 100644
index 0000000..cdd2c96
--- /dev/null
+++ b/tests/testthat/test-grf.R
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+test_that('grf classification', {
+  skip_if_not_installed("parsnip", minimum_version = "1.3.3.9000")
+  skip_if_not_installed("grf")
+  skip_if_not_installed("modeldata")
+
+  scat_dat <- modeldata::scat
+  scat_tr <- scat_dat[1:94, ]
+  scat_te <- scat_dat[95:110, ]
+
+  expect_snapshot(
+    rand_forest(mtry = 100, trees = 1, min_n = 1000) |>
+      set_engine("grf") |>
+      set_mode("classification") |>
+      translate()
+  )
+
+  expect_snapshot_warning(
+    rand_forest(mtry = 100) |>
+      set_engine("grf") |>
+      set_mode("classification") |>
+      fit(Species ~ ., data = scat_tr)
+  )
+
+  grf_spec <-
+    rand_forest() |>
+    set_engine("grf", seed = 1) |>
+    set_mode("classification")
+
+  set.seed(281)
+  grf_fit <- fit(grf_spec, Species ~ ., data = scat_tr)
+  expect_s3_class(grf_fit$fit, "probability_forest")
+
+  ###
+
+  grf_cls <- predict(grf_fit, scat_te)
+  expect_equal(nrow(grf_cls), nrow(scat_te))
+  expect_equal(
+    grf_cls[0, ],
+    structure(
+      list(
+        .pred_class = structure(
+          integer(0),
+          levels = c("bobcat", "coyote", "gray_fox"),
+          class = "factor"
+        )
+      ),
+      row.names = integer(0),
+      class = c("tbl_df", "tbl", "data.frame")
+    )
+  )
+
+  ###
+
+  grf_prb <- predict(grf_fit, scat_te, type = "prob")
+  expect_equal(nrow(grf_prb), nrow(scat_te))
+  expect_equal(
+    grf_prb[0, ],
+    structure(
+      list(
+        .pred_bobcat = numeric(0),
+        .pred_coyote = numeric(0),
+        .pred_gray_fox = numeric(0)
+      ),
+      row.names = integer(0),
+      class = c("tbl_df", "tbl", "data.frame")
+    )
+  )
+
+  ###
+
+  grf_ci <- predict(grf_fit, scat_te, type = "conf_int")
+  expect_equal(nrow(grf_ci), nrow(scat_te))
+  expect_equal(
+    grf_ci[0, ],
+    structure(
+      list(
+        .pred_lower_bobcat = numeric(0),
+        .pred_lower_coyote = numeric(0),
+        .pred_lower_gray_fox = numeric(0),
+        .pred_upper_bobcat = numeric(0),
+        .pred_upper_coyote = numeric(0),
+        .pred_upper_gray_fox = numeric(0)
+      ),
+      row.names = integer(0),
+      class = c("tbl_df", "tbl", "data.frame"),
+      level = 0.95
+    )
+  )
+})
+
+test_that('grf classification with case weights', {
+  skip_if_not_installed("parsnip", minimum_version = "1.3.3.9000")
+  skip_if_not_installed("grf")
+  skip_if_not_installed("modeldata")
+
+  scat_dat <- modeldata::scat
+  scat_tr <- scat_dat[1:94, ]
+  scat_te <- scat_dat[95:110, ]
+
+  set.seed(281)
+  scat_cw <-
+    scat_tr |>
+    mutate(
+      wts = hardhat::importance_weights(runif(nrow(scat_tr)))
+    )
+  not_missing <- complete.cases(scat_cw)
+
+  set.seed(281)
+  grf_wt_fit <- fit(
+    grf_spec,
+    Species ~ .,
+    data = scat_cw |> select(-wts),
+    case_weights = scat_cw$wts[not_missing]
+  )
+  expect_s3_class(grf_wt_fit$fit, "probability_forest")
+  expect_false(
+    isTRUE(
+      all.equal(
+        grf_wt_fit$fit$predictions,
+        grf_fit$fit$predictions
+      )
+    )
+  )
+  expect_equal(
+    grf_wt_fit$fit$sample.weights,
+    scat_cw$wts[not_missing]
+  )
+
+  set.seed(281)
+  grf_wf_fit <-
+    workflow(Species ~ ., grf_spec) |>
+    add_case_weights(wts) |>
+    fit(scat_cw)
+
+  expect_false(
+    isTRUE(
+      all.equal(
+        grf_fit$fit$predictions,
+        grf_wf_fit$fit$fit$fit$predictions
+      )
+    )
+  )
+  expect_equal(
+    grf_wf_fit$fit$fit$fit$sample.weights,
+    scat_cw$wts
+  )
+})
+
+test_that('grf regression', {
+  skip_if_not_installed("parsnip", minimum_version = "1.3.3.9000")
+  skip_if_not_installed("grf")
+  skip_if_not_installed("modeldata")
+
+  ames_dat <- modeldata::ames[1:100, ]
+  ames_tr <- ames_dat[1:90, ]
+  ames_te <- ames_dat[91:100, ]
+
+  expect_snapshot(
+    rand_forest(mtry = 100, trees = 1, min_n = 1000) |>
+      set_engine("grf") |>
+      set_mode("regression") |>
+      translate()
+  )
+
+  grf_spec <-
+    rand_forest() |>
+    set_engine("grf", seed = 101010101) |>
+    set_mode("regression")
+
+  set.seed(281)
+  grf_fit <- fit(grf_spec, Sale_Price ~ ., data = ames_tr)
+  expect_s3_class(grf_fit$fit, "regression_forest")
+
+  ###
+
+  grf_num <- predict(grf_fit, ames_te)
+  expect_equal(nrow(grf_num), nrow(ames_te))
+  expect_equal(
+    grf_num[0, ],
+    structure(
+      list(.pred = double(0)),
+      row.names = integer(0),
+      class = c("tbl_df", "tbl", "data.frame")
+    )
+  )
+
+  ###
+
+  grf_ci <- predict(grf_fit, ames_te, type = "conf_int")
+  expect_equal(nrow(grf_ci), nrow(ames_te))
+  expect_equal(
+    grf_ci[0, ],
+    structure(
+      list(.pred_lower = double(0), .pred_upper = double(0)),
+      row.names = integer(0),
+      class = c("tbl_df", "tbl", "data.frame"),
+      level = 0.95
+    )
+  )
+})
+
+test_that('grf regression with case weights', {
+  skip_if_not_installed("parsnip", minimum_version = "1.3.3.9000")
+  skip_if_not_installed("grf")
+  skip_if_not_installed("modeldata")
+
+  ames_dat <- modeldata::ames[1:100, ]
+  ames_tr <- ames_dat[1:90, ]
+  ames_te <- ames_dat[91:100, ]
+
+  set.seed(281)
+  ames_cw <-
+    ames_tr |>
+    mutate(
+      wts = hardhat::importance_weights(runif(nrow(ames_tr)))
+    )
+
+  set.seed(281)
+  grf_wt_fit <- fit(
+    grf_spec,
+    Sale_Price ~ .,
+    data = ames_cw |> select(-wts),
+    case_weights = ames_cw$wts
+  )
+  expect_s3_class(grf_wt_fit$fit, "regression_forest")
+  expect_false(
+    isTRUE(
+      all.equal(
+        grf_wt_fit$fit$predictions,
+        grf_fit$fit$predictions
+      )
+    )
+  )
+  expect_equal(
+    grf_wt_fit$fit$sample.weights,
+    ames_cw$wts
+  )
+
+  set.seed(281)
+  grf_wf_fit <-
+    workflow(Sale_Price ~ ., grf_spec) |>
+    add_case_weights(wts) |>
+    fit(ames_cw)
+
+  expect_false(
+    isTRUE(
+      all.equal(
+        grf_fit$fit$predictions,
+        grf_wf_fit$fit$fit$fit$predictions
+      )
+    )
+  )
+  expect_equal(
+    grf_wf_fit$fit$fit$fit$sample.weights,
+    ames_cw$wts
+  )
+})
+
+test_that('grf quantile regression', {
+  skip_if_not_installed("parsnip", minimum_version = "1.3.3.9000")
+  skip_if_not_installed("grf")
+  skip_if_not_installed("modeldata")
+
+  ames_dat <- modeldata::ames[1:100, ]
+  ames_tr <- ames_dat[1:90, ]
+  ames_te <- ames_dat[91:100, ]
+
+  expect_snapshot(
+    rand_forest(mtry = 100, trees = 1, min_n = 1000) |>
+      set_engine("grf") |>
+      set_mode("quantile regression", quantile_levels = (1:3) / 4) |>
+      translate()
+  )
+
+  grf_spec <-
+    rand_forest() |>
+    set_engine("grf") |>
+    set_mode("quantile regression", quantile_levels = (1:3) / 4)
+
+  set.seed(281)
+  grf_fit <- fit(grf_spec, Sale_Price ~ ., data = ames_tr)
+  expect_s3_class(grf_fit$fit, "quantile_forest")
+
+  ###
+
+  grf_qtl <- predict(grf_fit, ames_te)
+  expect_equal(nrow(grf_qtl), nrow(ames_te))
+  expect_equal(
+    grf_qtl[0, ],
+    structure(
+      list(
+        .pred_quantile = structure(
+          list(),
+          quantile_levels = c(0.25, 0.5, 0.75),
+          class = c("quantile_pred", "vctrs_vctr", "list")
+        )
+      ),
+      row.names = integer(0),
+      class = c("tbl_df", "tbl", "data.frame")
+    )
+  )
+})