projpred-related seed fix and docs/NEWS

NEWS.md

@@ -13,6 +13,7 @@ all additive predictor terms specified in the same formula. (#1492)
 and incompatible with the newly implemented global shrinkage prior framework.
 * No longer support multiple deprecated prior options for categorical and
 multivariate models after around 3 years of deprecation. (#1420)
+* Deprecate argument `newdata` of `get_refmodel.brmsfit()`. (#1502)
 
 ### Bug Fixes
 
@@ -95,6 +96,7 @@ over-dispersed and zero-inflated binomial response models thanks to Hayden
 Rabel. (#1319 & #1311)
 * Display `ppd_*` plots in `pp_check` via argument `prefix`. (#1313)
 * Support the `log` link in binomial and beta type families. (#1316)
+* Support **projpred**'s augmented-data projection. (#1292, #1294)
 
 ### Other changes
 

R/projpred.R

@@ -21,6 +21,9 @@
 #'   \code{TRUE} requires a \pkg{projpred} version >= 2.4.0.
 #' @param brms_seed A seed used to infer seeds for \code{\link{kfold.brmsfit}}
 #'   and for sampling group-level effects for new levels (in multilevel models).
+#'   If \code{NULL}, then \code{\link{set.seed}} is not called at all. If not
+#'   \code{NULL}, then the pseudorandom number generator (PRNG) state is reset
+#'   (to the state before calling this function) upon exiting this function.
 #' @param ... Further arguments passed to
 #' \code{\link[projpred:init_refmodel]{init_refmodel}}.
 #'
@@ -66,9 +69,11 @@ get_refmodel.brmsfit <- function(object, newdata = NULL, resp = NULL,
   # Infer "sub-seeds":
   if (exists(".Random.seed", envir = .GlobalEnv)) {
     rng_state_old <- get(".Random.seed", envir = .GlobalEnv)
-    on.exit(assign(".Random.seed", rng_state_old, envir = .GlobalEnv))
   }
   if (!is.null(brms_seed)) {
+    if (exists(".Random.seed", envir = .GlobalEnv)) {
+      on.exit(assign(".Random.seed", rng_state_old, envir = .GlobalEnv))
+    }
     set.seed(brms_seed)
   }
   kfold_seed <- sample.int(.Machine$integer.max, 1)
@@ -186,6 +191,10 @@ get_refmodel.brmsfit <- function(object, newdata = NULL, resp = NULL,
   }
 
   # prepare data passed to projpred
+  if (!is.null(newdata)) {
+    warning2("Argument 'newdata' of get_refmodel.brmsfit() is deprecated and ",
+             "will be removed in the future.")
+  }
   data <- current_data(
     object, newdata, resp = resp, check_response = TRUE,
     allow_new_levels = TRUE