more checks/tests for model and engine

Author: topepo

R/aaa_models.R

@@ -25,10 +25,9 @@ all_modes <- c("classification", "regression", "censored regression")
 
 # ------------------------------------------------------------------------------
 
-
 parsnip <- rlang::new_environment()
 parsnip$models <- NULL
-parsnip$modes <- c("regression", "classification", "unknown")
+parsnip$modes <- c(all_modes, "unknown")
 
 # ------------------------------------------------------------------------------
 
@@ -160,6 +159,23 @@ stop_incompatible_engine <- function(spec_engs, mode) {
   rlang::abort(msg)
 }
 
+stop_missing_engine <- function(cls) {
+  info <-
+    get_from_env(cls) %>%
+    dplyr::group_by(mode) %>%
+    dplyr::summarize(msg = paste0(unique(mode), " {",
+                                  paste0(unique(engine), collapse = ", "),
+                                  "}"),
+                     .groups = "drop")
+  if (nrow(info) == 0) {
+    rlang::abort(paste0("No known engines for `", cls, "()`."))
+  }
+  msg <- paste0(info$msg, collapse = ", ")
+  msg <- paste("Missing engine. Possible mode/engine combinations are:", msg)
+  rlang::abort(msg)
+}
+
+
 # check if class and mode and engine are compatible
 check_spec_mode_engine_val <- function(cls, eng, mode) {
   all_modes <- c("unknown", all_modes)
@@ -172,6 +188,7 @@ check_spec_mode_engine_val <- function(cls, eng, mode) {
   # Cases where the model definition is in parsnip but all of the engines
   # are contained in a different package
   if (nrow(model_info) == 0) {
+    check_mode_with_no_engine(cls, mode)
     return(invisible(NULL))
   }
 
@@ -219,6 +236,12 @@ check_spec_mode_engine_val <- function(cls, eng, mode) {
   invisible(NULL)
 }
 
+check_mode_with_no_engine <- function(cls, mode) {
+  spec_modes <- get_from_env(paste0(cls, "_modes"))
+  if (!(mode %in% spec_modes)) {
+    stop_incompatible_mode(spec_modes, cls)
+  }
+}
 
 check_engine_val <- function(eng) {
   if (rlang::is_missing(eng) || length(eng) != 1 || !is.character(eng))

R/arguments.R

@@ -79,7 +79,7 @@ set_mode <- function(object, mode) {
   cls <- class(object)[1]
   if (rlang::is_missing(mode)) {
     spec_modes <- rlang::env_get(get_model_env(), paste0(cls, "_modes"))
-    stop_incompatible_mode(spec_modes)
+    stop_incompatible_mode(spec_modes, cls)
   }
   check_spec_mode_engine_val(cls, object$engine, mode)
   object$mode <- mode

R/engines.R

@@ -71,16 +71,16 @@ load_libs <- function(x, quiet, attach = FALSE) {
 #' translate(mod, engine = "glmnet")
 #' @export
 set_engine <- function(object, engine, ...) {
+  mod_type <- class(object)[1]
   if (!inherits(object, "model_spec")) {
     rlang::abort("`object` should have class 'model_spec'.")
   }
 
   if (rlang::is_missing(engine)) {
-    avail_eng <- possible_engines(object)
-    stop_incompatible_engine(avail_eng)
+    stop_missing_engine(mod_type)
   }
   object$engine <- engine
-  check_spec_mode_engine_val(class(object)[1], object$engine, object$mode)
+  check_spec_mode_engine_val(mod_type, object$engine, object$mode)
 
   if (object$engine == "liquidSVM") {
     lifecycle::deprecate_soft(
@@ -90,7 +90,7 @@ set_engine <- function(object, engine, ...) {
   }
 
   new_model_spec(
-    cls = class(object)[1],
+    cls = mod_type,
     args = object$args,
     eng_args = enquos(...),
     mode = object$mode,

man/details_gen_additive_mod_mgcv.Rd

@@ -13,7 +13,7 @@ defaults <-
 param <-
  boost_tree() %>% 
   set_engine("C5.0") %>% 
-  set_mode("regression") %>% 
+  set_mode("classification") %>% 
   tunable() %>% 
   dplyr::select(-source, -component, -component_id, parsnip = name) %>% 
   dplyr::mutate(

man/extract-parsnip.Rd

@@ -13,7 +13,7 @@ defaults <-
 param <-
  decision_tree() %>% 
   set_engine("C5.0") %>% 
-  set_mode("regression") %>% 
+  set_mode("classification") %>% 
   tunable() %>% 
   dplyr::select(-source, -component, -component_id, parsnip = name) %>% 
   dplyr::mutate(

man/rmd/boost_tree_C5.0.Rmd

@@ -83,6 +83,25 @@ test_that("unavailable modes for an engine and vice-versa", {
     "Available modes for engine C5"
   )
 
+  expect_error(
+    proportional_hazards() %>% set_mode("regression"),
+    "Available modes for engine proportional_hazards"
+  )
+
+  expect_error(
+    linear_reg() %>% set_mode(),
+    "Available modes for engine linear_reg"
+  )
+
+  expect_error(
+    linear_reg() %>% set_engine(),
+    "Missing engine"
+  )
+
+  expect_error(
+    proportional_hazards() %>% set_engine(),
+    "No known engines for"
+  )
 })