merge pr #732: prompt on unavailable extension packages

Author: simonpcouch

NEWS.md

@@ -12,6 +12,8 @@
 
 * `predict(type = "prob")` will now provide an error if the outcome variable has a level called `"class"` (#720).
 
+* Model type functions will now message informatively if a needed parsnip extension package is not loaded (#731).
+
 # parsnip 0.2.1
 
 * Fixed a major bug in spark models induced in the previous version (#671).

R/arguments.R

@@ -67,7 +67,8 @@ set_args <- function(object, ...) {
     eng_args = object$eng_args,
     mode = object$mode,
     method = NULL,
-    engine = object$engine
+    engine = object$engine,
+    check_missing_spec = FALSE
   )
 }
 

R/bag_mars.R

@@ -47,7 +47,7 @@ print.bag_mars <- function(x, ...) {
   cat("Bagged MARS Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/bag_tree.R

@@ -51,7 +51,7 @@ print.bag_tree <- function(x, ...) {
   cat("Bagged Decision Tree Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/bart.R

@@ -95,7 +95,7 @@ print.bart <- function(x, ...) {
   cat("BART Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if(!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/boost_tree.R

@@ -84,7 +84,7 @@ print.boost_tree <- function(x, ...) {
   cat("Boosted Tree Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/c5_rules.R

@@ -68,7 +68,7 @@ print.C5_rules <- function(x, ...) {
   cat("C5.0 Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/cubist_rules.R

@@ -94,7 +94,7 @@ print.cubist_rules <- function(x, ...) {
   cat("Cubist Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/decision_tree.R

@@ -56,7 +56,7 @@ print.decision_tree <- function(x, ...) {
   cat("Decision Tree Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }

R/discrim_flexible.R

@@ -50,7 +50,7 @@ print.discrim_flexible <- function(x, ...) {
   cat("Flexible Discriminant Model Specification (", x$mode, ")\n\n", sep = "")
   model_printer(x, ...)
 
-  if (!is.null(x$method$fit$args)) {
+  if (is_printable_spec(x)) {
     cat("Model fit template:\n")
     print(show_call(x))
   }