Add mixture to brulee's tunable

NEWS.md

@@ -33,6 +33,8 @@
 
 * Fixed bug where some models fit using `fit_xy()` couldn't predict (#1166).
 
+* `tunable()` now references a dials object for the `mixture` parameter (#1236)
+
 ## Breaking Change
 
 * For quantile prediction, the `quantile` argument to `predict()` has been deprecate in facor of `quantile_levels`. This does not affect models with mode `"quantile regression"`. 

R/tunable.R

@@ -206,10 +206,9 @@ brulee_mlp_engine_args <-
     "largest",                         list(pkg = "dials", fun = "rate_largest"),
     "rate_schedule",                  list(pkg = "dials", fun = "rate_schedule"),
     "step_size",                     list(pkg = "dials", fun = "rate_step_size"),
-    "steps",                             list(pkg = "dials", fun = "rate_steps")
+    "mixture",                              list(pkg = "dials", fun = "mixture")
   ) %>%
-  dplyr::mutate(,
-                source = "model_spec",
+  dplyr::mutate(source = "model_spec",
                 component = "mlp",
                 component_id = "engine"
   )

parsnip.Rproj

@@ -1,4 +1,5 @@
 Version: 1.0
+ProjectId: 7f6c9ff5-6b9a-4235-8666-12db5ef65d49
 
 RestoreWorkspace: No
 SaveWorkspace: No

tests/testthat/test-tunable.R

@@ -0,0 +1,22 @@
+test_that('brulee has mixture object', {
+  # for issue 1236
+  mlp_spec <-
+    mlp(
+      hidden_units = tune(),
+      activation =  tune(),
+      penalty = tune(),
+      learn_rate = tune(),
+      epoch = 2000
+    ) %>%
+    set_mode("regression") %>%
+    set_engine("brulee",
+               stop_iter = tune(),
+               mixture = tune(),
+               rate_schedule = tune())
+
+  brulee_res <- tunable(mlp_spec)
+
+  expect_true(
+    length(brulee_res$call_info[brulee_res$name == "mixture"]) > 0
+  )
+})