Inputs component(s) in set_input can't be provided as variables

[gladkia]

Summary

It seems that in the current version of set_inputs one has to hard-code the input components.

App and evaluation

Please find a simple app with example uses of set_input below:

library(shinytest2) 

two_radio_buttons_app <- shinyApp(ui <- fluidPage(
  radioButtons("rd1", "rd1", letters[1:5]),
  radioButtons("rd2", "rd2", LETTERS[1:5]),
  textOutput("rd_out")
  
),
server <- function(input, output, session) {
  output$rd_out <-
    renderText(sprintf("info: rd1:%s rd2:%s", input$rd1, input$rd2))
  
})

app <- shinytest2::AppDriver$new(two_radio_buttons_app, name = "two_radio_buttons_app")
on.exit({
  print(app$get_logs())
  app$stop()
  rm(app)
})

test_that("evaluate `set_input`", {
  print("### providing input component as hard-coded data")
  print(app$get_value(input = "rd1"))
  app$set_inputs(rd1 = "b")
  print(app$get_value(input = "rd1"))
  app$set_inputs(rd1 = "e")
  print(app$get_value(input = "rd1"))
  
  print(app$get_value(input = "rd2"))
  app$set_inputs(rd2 = "C")
  print(app$get_value(input = "rd2"))
  app$set_inputs(rd2 = "D")
  print(app$get_value(input = "rd2"))
  
  print("### providing input component as variables")
  rd1_v1 <- "b"
  rd1_id <- "rd1"
  rd1_v2 <- "c"
  print(app$get_value(input = "rd1"))
  
  # value can be provided as variable
  app$set_inputs("rd1" = rd1_v1)
  print(app$get_value(input = "rd1"))
  
  # input component can be provided as variable (solution #1)
  app$set_inputs(`as.name(rd1_id)` = rd1_v2)
  print(app$get_value(input = "rd1"))
  
  # input component can be provided as variable (solution #2)
  rv <- structure(rd1_v2, names = rd1_id)
  app$set_inputs(rv)
  print(app$get_value(input = "rd1"))
})

Output from testthat

And here is the output of testthat::test_file("code_above.R")

[ FAIL 0 | WARN 0 | SKIP 0 | PASS 0 ][1] 
"### providing input component as hard-coded data"
[1] "a"
[1] "b"
[1] "e"
[1] "A"
[1] "C"
[1] "D"
[1] "### providing input component as variables"
[1] "e"
[1] "b"
[1] "b"
[ FAIL 1 | WARN 0 | SKIP 0 | PASS 0 ]{shinytest2} R  info   20:17:48.02 Start AppDriver initialization
(...)
{chromote}   JS info   20:17:54.55 shinytest2; Unable to find input binding for element with id as.name(rd1_id)
{shinytest2} R  info   20:17:54.55 Error received while setting inputs: Unable to find input binding for element with id as.name(rd1_id)
{shinytest2} R  info   20:17:54.66 Getting all values
{shinytest2} R  info   20:17:55.08 Setting inputs: ''
{shiny}      R  stderr ----------- Loading required package: shiny
{shiny}      R  stderr ----------- Running application in test mode.
{shiny}      R  stderr ----------- 
{shiny}      R  stderr ----------- Listening on http://127.0.0.1:5059

── Error (shinytest2.R:52): evaluate `set_input` ───────────────────────────────
Error in `app_queue_inputs(self, private, input_values)`: Assertion on 'rlang::is_named(inputs)' failed: Must be TRUE.
Backtrace:
 1. app$set_inputs(rv)
      at shinytest2.R:52:2
 2. shinytest2:::app_set_inputs(...)
      at shinytest2/R/app-driver.R:433:6
 3. shinytest2:::app_queue_inputs(self, private, input_values)
      at shinytest2/R/app-driver-set-inputs.R:43:2
 4. checkmate::assert_true(rlang::is_named(inputs))
      at shinytest2/R/app-driver-set-inputs.R:72:2
 5. checkmate::makeAssertion(x, res, .var.name, add)
 6. checkmate:::mstop(...)

[ FAIL 1 | WARN 0 | SKIP 0 | PASS 0 ]

[gadenbuie]

Hi @gladkia, thanks for posting this issue and for following up with a PR!

As you may have noticed while looking at the source code, $set_inputs() uses rlang::list2(...) to process the input values. This function supports !!!, the splicing operator, so you can construct a list outside of set_inputs() and use it to set the input values.

all_to_value_b <- list(rd1 = "b", rd2 = "B")
app$set_inputs(!!!all_to_value_b)

[gladkia]

Hi @gadenbuie,

Thanks for the quick answer. Awesome. Now I see how powerful the solution with rlang::list2(...) is :)!

It would be great to add some info to the vignette and maybe sth in the tests to let the users know that such a great and simple solution is possible :). I mean sth similar to the updated version of the PR.

[gadenbuie]

Thanks @gladkia, I agree it would be helpful to mention this in the documentation and think your updated PR is a good start! Barret will likely review your PR when we pick up work in shinytest2 again (please don't be alarmed if it takes a little while for us to get to it).