test parsnip "overhead"

tests/testthat/test_fit_interfaces.R

@@ -154,3 +154,23 @@ test_that("fit() can handle attributes on a vector outcome", {
     ignore_attr = TRUE
   )
 })
+
+test_that("overhead of parsnip interface is minimal (#1071)", {
+  skip_on_cran()
+  skip_on_covr()
+
+  timing <- function(expr) {
+    expr <- substitute(expr)
+    system.time(replicate(100, eval(expr)))[["elapsed"]]
+  }
+
+  time_engine <-
+    timing(lm(mpg ~ ., mtcars))
+  time_parsnip_form <-
+    timing(fit(linear_reg(), mpg ~ ., mtcars))
+  time_parsnip_xy <-
+    timing(fit_xy(linear_reg(), mtcars[2:11], mtcars[1]))
+
+  expect_true(time_parsnip_form / time_engine < 4.5)
+  expect_true(time_parsnip_xy / time_engine < 6)
+})