DeleteFile = FALSE in renderImage doesn't work

I have a problem with the deleteFile = FALSE argument for renderImage. In short, it deletes the image file anyway.

As a short test case, I have ui.R

 library(shiny)              
 shinyUI(fluidPage(
   titlePanel("Testing ..."),  
   sidebarLayout(   
       sidebarPanel(),            
       mainPanel(
          imageOutput("f1")
       )
   )     
 ))

      

        
        
        
      

    

and server.R

library(shiny)

shinyServer(function(input, output,session) {

   output$f1 <- renderImage({
      list(src="f1.png", deleteFile = FALSE)
   }) 
})

      

        
        
        
      

    

where f1.png is some png image file. When I run this, it displays the image ok, but also deletes it from the folder, exactly what deleteFile = FALSE shouldn't do.

I'm on a Win7 machine, if that matters.

Wolfgang

Added: I have now found another way to do it using

output$f1 <- renderText({
    HTML("<img src=\"f1.png\">")
})

      

        
        
        
      

    

and uiOutput in ui.R and that works great, but the original question remains, why are brilliant ones deleting image files despite the deleteFile = FALSE argument?

Wolfgang