From d08a2507fa4e51860ea136f96074bf87013cdc42 Mon Sep 17 00:00:00 2001
From: Jonathan McPherson <jonathan@rstudio.com>
Date: Thu, 24 Apr 2014 15:28:07 -0700
Subject: [PATCH] fail when attempting to insert a shiny app into a cached
 chunk

---
 R/app.R | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/R/app.R b/R/app.R
index 786c914eb..2ae2660c3 100644
--- a/R/app.R
+++ b/R/app.R
@@ -240,6 +240,8 @@ knit_print.shiny.appobj <- function(x, ...) {
       "Shiny applications not supported in static R Markdown documents")
   }
   else {
+    if (isTRUE(as.logical(knitr::opts_current$get("cache"))))
+      stop("Shiny applications cannot be used in cached chunks.")
     path <- addSubApp(x)
     output <- tags$iframe(src=path, width=width, height=height,
                           class="shiny-frame")