changes for #208

Author: topepo

NEWS.md

@@ -2,6 +2,8 @@
 
 * Some default parameter ranges were updated for SVM, KNN, and MARS models. 
 
+* [A bug](https://github.com/tidymodels/parsnip/issues/208) was fixed related to using data descriptors and `fit_xy()`. 
+
 # parsnip 0.0.3.1
 
 Test case update due to CRAN running extra tests [(#202)](https://github.com/tidymodels/parsnip/issues/202)

R/fit_helpers.R

@@ -79,7 +79,7 @@ xy_xy <- function(object, env, control, target = "none", ...) {
 
   # if descriptors are needed, update descr_env with the calculated values
   if (requires_descrs(object)) {
-    data_stats <- get_descr_form(env$formula, env$data)
+    data_stats <- get_descr_xy(env$x, env$y)
     scoped_descrs(data_stats)
   }
 

tests/testthat/test_descriptors.R

@@ -249,3 +249,21 @@ test_that("can be temporarily overriden at evaluation time", {
 })
 
 
+# ------------------------------------------------------------------------------
+
+test_that("system-level descriptor tests", {
+  skip_if_not_installed("xgboost")
+  expect_error(
+    boost_tree(mode = "regression", mtry = .cols()) %>%
+      set_engine("xgboost") %>%
+      fit_xy(x = mtcars[, -1], y = mtcars$mpg),
+    NA
+  )
+  expect_error(
+    boost_tree(mode = "regression", mtry = .cols()) %>%
+      set_engine("xgboost") %>%
+      fit(mpg ~ ., data = mtcars),
+    NA
+  )
+
+})