Testing Deep Stack Traces

[shikokuchuo]

I think it was mentioned that deep stack traces aren't currently being tested.

This was precisely the one thing that I nearly broke prior to releasing mirai 2.5.0.

library(shiny)
library(mirai)

ui <- fluidPage(
  textOutput("out")
)

server <- function(input, output, session) {
  output$out <- renderText({
    mirai({
      Sys.sleep(1)
      elephant()
    })
  })
}

shinyApp(ui, server)

The above should throw a warning in the console, showing the deep stack trace.

@schloerke if shinytest2 can already handle this, then I suggest we find a way to get this into shinycoreci. Otherwise let's think of a way to do this other than manually! Thanks.

[schloerke]

@shikokuchuo Sorry for the mis communication.

Shiny does have it in test-stacks.R and test-deep-stacks.R.

In our IRL convo I was trying to go for "if other packages are going to test deep stack traces. If they do, it will change."

And when testthat is released, the stacks will break again.

[shikokuchuo]

Right - I do remember you saying that. It was more the "it will change" part that was slightly alarming, in that I wasn't sure what that entailed. If it's just snapshot output that's of no concern to me.

The breakage I was referring to above was of the evaluation stack not being found (because the error was not thrown from a promise domain-wrapped then()) - so the deep stack trace mechanism would error. I guess that can only be an error on my part!

But nevertheless it would be comforting to test the above snippet in shinycoreci - should I transfer the issue there?