Disable autoloading with a R/_disable_autoload.R file.

Author: trestletech

R/app.R

@@ -314,9 +314,9 @@ initAutoReloadMonitor <- function(dir) {
 #' adjacent to the `app.R`/`server.R`/`ui.R` files.
 #'
 #' Since Shiny 1.5.0, this function is called by default when running an
-#' application. If it causes problems, you can opt out by using
-#' `options(shiny.autoload.r=FALSE)`. Note that in a future version of Shiny,
-#' this option will no longer be available. If you set this option, it will
+#' application. If it causes problems, there are two ways to opt out. You can
+#' either place a file named `_disable_autoload.R` in your R/ directory, or
+#' set `options(shiny.autoload.r=FALSE)`. If you set this option, it will
 #' affect any application that runs later in the same R session, potentially
 #' breaking it, so after running your application, you should unset option with
 #' `options(shiny.autoload.r=NULL)`
@@ -339,6 +339,13 @@ loadSupport <- function(appDir, renv=new.env(parent=globalenv()), globalrenv=glo
   }
 
   helpersDir <- file.path(appDir, "R")
+
+  disabled <- list.files(helpersDir, pattern="_disable_autoload\\.r$", recursive=FALSE, ignore.case=TRUE)
+  if (length(disabled) > 0){
+    message("R/_disable_autoload.R detected; not loading the R/ directory automatically")
+    return(invisible(renv))
+  }
+
   helpers <- list.files(helpersDir, pattern="\\.[rR]$", recursive=FALSE, full.names=TRUE)
 
   if (length(helpers) > 0){

man/loadSupport.Rd

@@ -0,0 +1,2 @@
+
+helper2 <- "abc"

tests/test-helpers/app6-disabled/R/_DISABLE_autoload.r

@@ -0,0 +1,2 @@
+
+helper1 <- 123

tests/test-helpers/app6-disabled/R/helperCap.R

@@ -0,0 +1,2 @@
+
+helper2 <- "abc"

tests/test-helpers/app6-disabled/R/helperLower.r

@@ -0,0 +1 @@
+global <- "ABC"

tests/test-helpers/app6-disabled/global.R

@@ -24,6 +24,12 @@ test_that("loadSupport messages to inform about loading", {
                  "Automatically loading 1 .R file")
 })
 
+test_that("loadSupport skips if _disable_autoload.R found", {
+  expect_message(loadSupport(test_path("../test-helpers/app6-disabled"), renv=environment(), globalrenv=NULL),
+                 "disable_autoload.R detected; not loading")
+  expect_false(exists("helper1"))
+})
+
 test_that("Can suppress sourcing global.R", {
   # Confirm that things blow up if we source global.R
   expect_error(loadSupport(test_path("../test-helpers/app3-badglobal")))