fix: add default S3 methods to varPro-family wrappers (gg_isopro, gg_beta_varpro, gg_ivarpro) (#136)

* fix(gg_isopro): add default S3 method, remove dead inner guard

gg_isopro had no default method: the friendly "expects an isopro object"
stop() lived inside gg_isopro.isopro, which is only reachable when the
object already inherits 'isopro', so it was dead code. A wrong-class input
got R's stock "no applicable method for 'gg_isopro'" error instead.

Add gg_isopro.default emitting the clear class error (matching the
gg_beta_uvarpro / gg_sdependent pattern) and drop the unreachable inner
check. Adds a dispatch-error test (needs no varPro fit, runs on CRAN).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* fix(gg_beta_varpro,gg_ivarpro): add default S3 methods, remove dead guards

Same fix as gg_isopro, extended to its two varPro-family siblings so the
whole family is consistent with gg_beta_uvarpro / gg_sdependent. Each had an
unreachable `if (!inherits(object, "varpro")) stop(...)` inside its .varpro
method; a wrong-class input got R's generic "no applicable method" error.

Add gg_beta_varpro.default and gg_ivarpro.default emitting the clear class
error, drop the dead inner guards, and add fit-free dispatch-error tests
(run on CRAN). The 6 classic wrappers (gg_error/gg_vimp/gg_variable/
gg_rfsrc/gg_roc/gg_brier) still lack .default but have no dead guards and
are deferred to a post-release consistency pass.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* refactor(gg_beta_uvarpro): drop dead inner class guard

gg_beta_uvarpro already has a .default method (added with the wrapper), but
its .uvarpro method still carried the unreachable `if (!inherits(object,
"uvarpro")) stop(...)` guard. Remove it so the whole varPro family is
consistent (no dead guards, class errors handled by .default). Behavior is
unchanged — wrong-class input still errors via gg_beta_uvarpro.default.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: ehrlinger

NAMESPACE

@@ -22,12 +22,15 @@ S3method(calc_roc,randomForest)
 S3method(calc_roc,rfsrc)
 S3method(gg_beta_uvarpro,default)
 S3method(gg_beta_uvarpro,uvarpro)
+S3method(gg_beta_varpro,default)
 S3method(gg_beta_varpro,varpro)
 S3method(gg_brier,rfsrc)
 S3method(gg_error,randomForest)
 S3method(gg_error,randomForest.formula)
 S3method(gg_error,rfsrc)
+S3method(gg_isopro,default)
 S3method(gg_isopro,isopro)
+S3method(gg_ivarpro,default)
 S3method(gg_ivarpro,varpro)
 S3method(gg_rfsrc,randomForest)
 S3method(gg_rfsrc,rfsrc)

NEWS.md

@@ -3,6 +3,12 @@ Version: 3.4.0
 
 ggRandomForests v3.4.0
 ======================
+* `gg_isopro()`, `gg_beta_varpro()`, and `gg_ivarpro()` now have `default` S3
+  methods, so a wrong-class input gives a clear "expected a '<class>' object"
+  error (naming the class it got) instead of R's generic "no applicable
+  method". This makes the varPro-family wrappers consistent with
+  `gg_beta_uvarpro()` / `gg_sdependent()`; the previously-unreachable inner
+  class checks were removed.
 * Fix: `gg_partial_rfsrc()` now computes partial dependence correctly for
   `factor` predictors. It was passing factor *labels* as
   `partial.values` to `randomForestSRC::partial.rfsrc()`, which imposes a

R/gg_beta_uvarpro.R

@@ -77,10 +77,6 @@ gg_beta_uvarpro.default <- function(object, ..., cutoff = NULL,
 #' @export
 gg_beta_uvarpro.uvarpro <- function(object, ..., cutoff = NULL,
                                     beta_fit = NULL) {
-  if (!inherits(object, "uvarpro")) {
-    stop("gg_beta_uvarpro: expected a 'uvarpro' object from varPro::uvarpro().",
-         call. = FALSE)
-  }
   .assert_scalar_numeric_or_null(cutoff, "cutoff", "gg_beta_uvarpro")
 
   # Resolve the beta matrix (cache path)

R/gg_beta_varpro.R

@@ -183,13 +183,17 @@ gg_beta_varpro <- function(object, ..., cutoff = NULL, beta_fit = NULL,
   UseMethod("gg_beta_varpro", object)
 }
 
+#' @export
+gg_beta_varpro.default <- function(object, ..., cutoff = NULL,
+                                   beta_fit = NULL, which_class = NULL) {
+  stop("gg_beta_varpro: expected a 'varpro' object from varPro::varpro(); ",
+       "got an object of class ", paste(class(object), collapse = "/"), ".",
+       call. = FALSE)
+}
+
 #' @export
 gg_beta_varpro.varpro <- function(object, ..., cutoff = NULL,
                                   beta_fit = NULL, which_class = NULL) {
-  if (!inherits(object, "varpro")) {
-    stop("gg_beta_varpro: expected a 'varpro' object from varPro::varpro().",
-         call. = FALSE)
-  }
   fam <- object$family
   if (!fam %in% c("regr", "class")) {
     stop(sprintf(

R/gg_isopro.R

@@ -172,12 +172,14 @@ gg_isopro <- function(object, ..., newdata = NULL) {
 }
 
 #' @export
-gg_isopro.isopro <- function(object, ..., newdata = NULL) {
-  if (!inherits(object, "isopro")) {
-    stop("gg_isopro expects a 'isopro' object from varPro::isopro().",
-         call. = FALSE)
-  }
+gg_isopro.default <- function(object, ..., newdata = NULL) {
+  stop("gg_isopro: expected an 'isopro' object from varPro::isopro(); ",
+       "got an object of class ", paste(class(object), collapse = "/"), ".",
+       call. = FALSE)
+}
 
+#' @export
+gg_isopro.isopro <- function(object, ..., newdata = NULL) {
   ntree <- tryCatch(
     as.integer(object$isoforest$ntree),
     error = function(e) NA_integer_

R/gg_ivarpro.R

@@ -158,14 +158,19 @@ gg_ivarpro <- function(object, ..., which_obs = NULL, which_class = NULL,
   UseMethod("gg_ivarpro", object)
 }
 
+#' @export
+gg_ivarpro.default <- function(object, ..., which_obs = NULL,
+                               which_class = NULL, cutoff = NULL,
+                               ivarpro_fit = NULL) {
+  stop("gg_ivarpro: expected a 'varpro' object from varPro::varpro(); ",
+       "got an object of class ", paste(class(object), collapse = "/"), ".",
+       call. = FALSE)
+}
+
 #' @export
 gg_ivarpro.varpro <- function(object, ..., which_obs = NULL,
                               which_class = NULL, cutoff = NULL,
                               ivarpro_fit = NULL) {
-  if (!inherits(object, "varpro")) {
-    stop("gg_ivarpro: expected a 'varpro' object from varPro::varpro().",
-         call. = FALSE)
-  }
   fam <- object$family
   if (!fam %in% c("regr", "class")) {
     stop(sprintf(

tests/testthat/test_gg_beta_varpro.R

@@ -1,3 +1,10 @@
+test_that("gg_beta_varpro: non-varpro input errors via the default method", {
+  # No varPro fit needed — the default method fires before any varpro work.
+  expect_error(gg_beta_varpro(data.frame(a = 1:3)),
+               "expected a 'varpro' object")
+  expect_error(gg_beta_varpro(1:3), "got an object of class integer")
+})
+
 test_that("gg_beta_varpro returns the expected tidy shape", {
   b <- .beta_fit_mtcars()
   v <- .varpro_mtcars()

tests/testthat/test_gg_isopro.R

@@ -19,6 +19,15 @@ make_iso_fit <- function(seed = 1L, method = "rnd", ntree = 25, sampsize = 16) {
   )
 }
 
+test_that("gg_isopro: non-isopro input errors via the default method", {
+  # No varPro fit needed — the default method fires before any isopro work,
+  # so this runs everywhere (incl. CRAN).
+  expect_error(gg_isopro(data.frame(a = 1:3)),
+               "expected an 'isopro' object")
+  expect_error(gg_isopro(1:3),
+               "got an object of class integer")
+})
+
 test_that("gg_isopro: returns gg_isopro data.frame with correct columns", {
   fit <- make_iso_fit()
   gg  <- gg_isopro(fit)

tests/testthat/test_gg_ivarpro.R

@@ -1,3 +1,12 @@
+# ---- Dispatch --------------------------------------------------------------
+
+test_that("gg_ivarpro: non-varpro input errors via the default method", {
+  # No varPro fit needed — the default method fires before any varpro work.
+  expect_error(gg_ivarpro(data.frame(a = 1:3)),
+               "expected a 'varpro' object")
+  expect_error(gg_ivarpro(1:3), "got an object of class integer")
+})
+
 # ---- Shape ----------------------------------------------------------------
 
 test_that("gg_ivarpro regression returns long-format tidy frame", {