selectInput with selectize = T (Default) removes duplicate values in choices without a warning()

[yogat3ch]

My specific question was already kindly answered by @wch in #2693. However, it raised an issue around selectize/selectize.js#129 filtering duplicate choices without giving the user a warning or message indicating that it's doing so.

Example application or steps to reproduce the problem

library(shiny)

carrier_choices <- list(
  `Page Plus Cellular (Verizon)` = "number@vzwpix.com",
  `Verizon Wireless` = "number@vzwpix.com"
)
ui <- function(id){
  fluidPage(
    selectInput("b1_carrier", "Carrier", choices = carrier_choices)
  )
}

server <- function(input, output, session) { }
shinyApp(ui, server)

Describe the problem in detail

Note that only the first item shows up because there are duplicate values. If there's a way to warn the developer of this behavior that would probably save them the time trying to figure out where their choices went in a large choice set! 😖

[yogat3ch]

Solved in #2693