Fix tempdir() issue in test case & update doc.

Author: yanboliang

R/pkg/R/context.R

@@ -236,7 +236,7 @@ setCheckpointDir <- function(sc, dirName) {
 #'
 #' @rdname spark.addFile
 #' @param path The path of the file to be added
-#' @param recursive Recursive or not if the path is directory. Default is FALSE.
+#' @param recursive Whether to add files recursively from the path. Default is FALSE.
 #' @export
 #' @examples
 #'\dontrun{

R/pkg/inst/tests/testthat/test_context.R

@@ -180,7 +180,8 @@ test_that("add and get file to be downloaded with Spark job on every node", {
   unlink(path)
 
   # Test add directory recursively.
-  path <- tempdir()
+  path <- paste0(tempdir(), "/", "recursive_dir")
+  dir.create(path)
   dir_name <- basename(path)
   path1 <- paste0(path, "/", "hello.txt")
   file.create(path1)