Interrupt or error during callback causes terminal to not echo output

[wch]

If you run this code in a terminal, then press Ctrl-C before it finishes, then quit R, the terminal will no longer echo text that is typed. Running reset restores it to normal.

R
library(later)

later(function() {
  cat("start...")
  Sys.sleep(5)
  cat("done.\n")
})

However, catching the interrupt prevents the problem:

R
library(later)

later(function() {
  cat("start...")
  tryCatch({
    Sys.sleep(5)
  }, 
  interrupt = function(e) {
    cat("interrupt")
  })
  cat("done.\n")
})

Some more information about this type of problem: https://askubuntu.com/a/172747/131896

In itself, this isn't a big problem, but it makes me wonder if other things are not being cleaned up properly.

> sessioninfo::session_info()
─ Session info ───────────────────────────────────────────────────────────────
 setting  value                       
 version  R version 3.4.2 (2017-09-28)
 os       macOS High Sierra 10.13.1   
 system   x86_64, darwin15.6.0        
 ui       X11                         
 language (EN)                        
 collate  en_US.UTF-8                 
 tz       <NA>                        
 date     2017-11-21                  

─ Packages ───────────────────────────────────────────────────────────────────
 package     * version    date       source                      
 clisymbols    1.2.0      2017-05-21 CRAN (R 3.4.0)              
 later       * 0.6.0.9000 2017-11-21 Github (r-lib/later@c1c3b09)
 Rcpp          0.12.13    2017-09-28 cran (@0.12.13)             
 sessioninfo   1.0.0      2017-06-21 CRAN (R 3.4.1)              
 withr         2.1.0      2017-11-01 CRAN (R 3.4.2)              

[wch]

The same happens if there's an error in the callback:

later::later(function() {
  stop("asdf")
})