Running examples in 'fabletools-Ex.R' failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: accuracy
> ### Title: Evaluate accuracy of a forecast or model
> ### Aliases: accuracy accuracy.mdl_df accuracy.fbl_ts
> 
> ### ** Examples
> 
> if (requireNamespace("fable", quietly = TRUE)) {
+ library(fable)
+ library(tsibble)
+ library(tsibbledata)
+ library(dplyr)
+ 
+ fit <- aus_production %>%
+   filter(Quarter < yearquarter("2006 Q1")) %>% 
+   model(ets = ETS(log(Beer) ~ error("M") + trend("Ad") + season("A")))
+ 
+ # In-sample training accuracy does not require extra data provided.
+ accuracy(fit)
+ 
+ # Out-of-sample forecast accuracy requires the future values to compare with.
+ # All available future data will be used, and a warning will be given if some
+ # data for the forecast window is unavailable.
+ fc <- fit %>% 
+   forecast(h = "5 years")
+ fc %>% 
+   accuracy(aus_production)
+   
+ # It is also possible to compute interval and distributional measures of
+ # accuracy for models and forecasts which give forecast distributions.
+ fc %>% 
+   accuracy(
+     aus_production,
+     measures = list(interval_accuracy_measures, distribution_accuracy_measures)
+   )
+ }

Attaching package: 'dplyr'

The following object is masked from 'package:tsibble':

    id

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Warning: The future dataset is incomplete, incomplete out-of-sample data will be treated as missing. 
2 observations are missing between 2010 Q3 and 2010 Q4
Error: `vars` must be a character vector.
Backtrace:
     x
  1. \-fc %>% accuracy(aus_production)
  2.   +-base::withVisible(eval(quote(`_fseq`(`_lhs`)), env, env))
  3.   \-base::eval(quote(`_fseq`(`_lhs`)), env, env)
  4.     \-base::eval(quote(`_fseq`(`_lhs`)), env, env)
  5.       \-`_fseq`(`_lhs`)
  6.         \-magrittr::freduce(value, `_function_list`)
  7.           +-base::withVisible(function_list[[k]](value))
  8.           \-function_list[[k]](value)
  9.             +-fabletools::accuracy(., aus_production)
 10.             \-fabletools:::accuracy.fbl_ts(., aus_production)
 11.               +-dplyr::transmute(object, .fc = !!resp, .dist = !!dist, !!!syms(by))
 12.               \-tsibble:::transmute.tbl_ts(...)
 13.                 +-dplyr::mutate(.data, !!!lst_quos)
 14.                 +-fabletools:::mutate.fbl_ts(.data, !!!lst_quos)
 15.                 | \-fabletools::as_fable(...)
 16.                 +-base::NextMethod()
 17.                 \-tsibble:::mutate.tbl
Execution halted