Inconsistency with selectInput when choices=NULL in regards of multiple parameter

[Raphael N]

Hello everyone,

I have two selectInput. One with multiple = TRUE and one with multiple = FALSE. Both of them have the choices parameter equals to NULL.

With the one input with multiple=TRUE, the input value is NULL.

With the other one, it forces it to "".

I have been in the code under it and it seems that in that case shiny:::selectizeIt will always put the argument nonempty to TRUE and so the value will be forced to "".

Is there a way to force having a NULL value ?

Here is a code to demonstrate this issue :

library(shiny)

ui <- fluidPage(

  column(6,

         selectInput(inputId = "input1",

                     label = "input1",

                     choices = NULL,

                     selected = NULL,

                     multiple = FALSE

                     ),

         verbatimTextOutput("output1")

  ),

  column(6,

         selectInput(inputId = "input2",

                     label = "input2",

                     choices = NULL,

                     selected = NULL,

                     multiple = TRUE

                     ),

         verbatimTextOutput("output2")

  )

)

server <- shinyServer(function(input, output, session){

  output$output1 <- renderPrint(

    list(choices = input$input1,

         is.null = is.null(input$input1),

         length = length(input$input1))

  )

  output$output2 <- renderPrint(

    list(choices = input$input2,

         is.null = is.null(input$input2),

         length = length(input$input2))

  )

})

shinyApp(ui, server)

Thanks