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Register expressions for export in test mode

exportTestValues(..., quoted_ = FALSE, env_ = parent.frame(),
  session_ = getDefaultReactiveDomain())


... Named arguments that are quoted or unquoted expressions that will be captured and evaluated when snapshot URL is visited.
quoted_ Are the expression quoted? Default is FALSE.
env_ The environment in which the expression should be evaluated.
session_ A Shiny session object.


This function registers expressions that will be evaluated when a test export event occurs. These events are triggered by accessing a snapshot URL.


This function only has an effect if the app is launched in test mode. This is done by calling runApp() with test.mode=TRUE, or by setting the global option shiny.testmode to TRUE.


## Only run this example in interactive R sessions if (interactive()) { options(shiny.testmode = TRUE) # This application shows the test snapshot URL; clicking on it will # fetch the input, output, and exported values in JSON format. shinyApp( ui = basicPage( h4("Snapshot URL: "), uiOutput("url"), h4("Current values:"), verbatimTextOutput("values"), actionButton("inc", "Increment x") ), server = function(input, output, session) { vals <- reactiveValues(x = 1) y <- reactive({ vals$x + 1 }) observeEvent(input$inc, { vals$x <<- vals$x + 1 }) exportTestValues( x = vals$x, y = y() ) output$url <- renderUI({ url <- session$getTestSnapshotUrl(format="json") a(href = url, url) }) output$values <- renderText({ paste0("vals$x: ", vals$x, "\ny: ", y()) }) } ) }