questioning unnest_tsibble()

R/tidyr-verbs.R

@@ -167,13 +167,12 @@ unnest_check_tsibble <- function(data, key, index) {
   data
 }
 
+#' Unnest a data frame consisting of tsibbles to a tsibble
+#'
 #' @param data A data frame contains homogenous tsibbles in the list-columns.
 #' @param cols Names of columns to unnest.
 #' @inheritParams as_tsibble
 #' @keywords internal
-#' @examples
-#' nested_stock %>% 
-#'   unnest_tsibble(cols = data, key = stock)
 #' @export
 unnest_tsibble <- function(data, cols, key = NULL, validate = TRUE) {
   if (missing(cols)) {
@@ -195,13 +194,13 @@ unnest_tsibble <- function(data, cols, key = NULL, validate = TRUE) {
     new_lst <- unnested_names[map_lgl(unnested_data, is_list)]
     old_lst <- data_names[map_lgl(data, is_list)]
     lst_cols <- setdiff(old_lst, new_lst)
-    # checking if the nested columns has `tbl_ts` class (only for the first row)
-    first_nested <- data[lst_cols][1L, ]
-    eval_col <- purrr::imap(first_nested, dplyr::first)
-    tsbl_col <- map_lgl(eval_col, is_tsibble)
+    # checking if the nested columns has `tbl_ts` class
+    tsbl_col <- map_lgl(data[lst_cols], validate_list_of_tsibble)
     if (sum(tsbl_col) == 0) {
-      abort("Unnested columns contain no tsibble object.")
+      abort("Unnested columns contain no tsibble columns.")
     }
+    first_nested <- data[lst_cols][1L, ]
+    eval_col <- purrr::imap(first_nested, dplyr::first)
 
     tsbl <- eval_col[tsbl_col][[1L]]
     idx <- index(tsbl)

tests/testthat/test-tidyr.R

@@ -196,7 +196,7 @@ test_that("dplyr verbs for lst_ts", {
   # )
   expect_error(
     unnest_tsibble(nest_t %>% mutate(data = 1), cols = data),
-    "contain no tsibble object."
+    "contain no tsibble columns."
   )
   expect_is(nest_t %>% select(data2 = data), "lst_ts")
   expect_is(nest_t %>% group_by(State), "grouped_df")