[R] remove default values in internal booster manipulation functions (#9461)

R-package/R/xgb.load.R

@@ -35,7 +35,12 @@ xgb.load <- function(modelfile) {
   if (is.null(modelfile))
     stop("xgb.load: modelfile cannot be NULL")
 
-  handle <- xgb.Booster.handle(modelfile = modelfile)
+  handle <- xgb.Booster.handle(
+    params = list(),
+    cachelist = list(),
+    modelfile = modelfile,
+    handle = NULL
+  )
   # re-use modelfile if it is raw so we do not need to serialize
   if (typeof(modelfile) == "raw") {
     warning(
@@ -45,9 +50,9 @@ xgb.load <- function(modelfile) {
         " `xgb.unserialize` instead. "
       )
     )
-    bst <- xgb.handleToBooster(handle, modelfile)
+    bst <- xgb.handleToBooster(handle = handle, raw = modelfile)
   } else {
-    bst <- xgb.handleToBooster(handle, NULL)
+    bst <- xgb.handleToBooster(handle = handle, raw = NULL)
   }
   bst <- xgb.Booster.complete(bst, saveraw = TRUE)
   return(bst)