From f93c6dbcaa1c5f90790e8159b1387b999e8fe8ce Mon Sep 17 00:00:00 2001
From: Salim B <git@salim.space>
Date: Wed, 18 Oct 2023 18:48:38 +0200
Subject: [PATCH] Set RNG seed for htmlwidgets IDs (#2294)

`htmlwidgets::setWidgetIdSeed()` needs to be explicitly called for this due to how `htmlwidgets:::createWidgetId()` works
---
 NEWS.md                    | 1 +
 R/build-reference.R        | 7 +++++--
 man/build_reference.Rd     | 4 ++--
 man/build_site.Rd          | 4 ++--
 vignettes/test/widgets.Rmd | 2 +-
 5 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 015e838b00..0a1ea665d0 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -4,6 +4,7 @@
 * Remove redundant entries in the documentation index when multiple explicit `@usage` tags are provided (@klmr, #2302)
 * The article index now sorts vignettes and non-vignette articles alphabetically by their filename (literally, their `basename()`), by default (@jennybc, #2253).
 * Add Catalan translation (@jmaspons, #2333)
+* Set RNG seed for htmlwidgets IDs. This reduces noise in pkgdown reference HTML output when examples generate htmlwidgets (@salim-b, #2294).
 
 # pkgdown 2.0.7
 
diff --git a/R/build-reference.R b/R/build-reference.R
index ef8c94e53d..add462c13a 100644
--- a/R/build-reference.R
+++ b/R/build-reference.R
@@ -139,8 +139,8 @@
 #'   rapidly prototype. It is set to `FALSE` by [build_site()].
 #' @param run_dont_run Run examples that are surrounded in \\dontrun?
 #' @param examples Run examples?
-#' @param seed Seed used to initialize so that random examples are
-#'   reproducible.
+#' @param seed Seed used to initialize random number generation so that
+#'   examples are reproducible.
 #' @param devel Determines how code is loaded in order to run examples.
 #'   If `TRUE` (the default), assumes you are in a live development
 #'   environment, and loads source package with [pkgload::load_all()].
@@ -223,6 +223,9 @@ examples_env <- function(pkg, seed = 1014, devel = TRUE, envir = parent.frame())
   width <- purrr::pluck(pkg, "meta", "code", "width", .default = 80)
   withr::local_options(width = width, .local_envir = envir)
   withr::local_seed(seed)
+  if (requireNamespace("htmlwidgets", quietly = TRUE)) {
+    htmlwidgets::setWidgetIdSeed(seed)
+  }
 
   examples_env <- child_env(globalenv())
   if (file_exists(pre_path)) {
diff --git a/man/build_reference.Rd b/man/build_reference.Rd
index 81561844a4..730c2e2a36 100644
--- a/man/build_reference.Rd
+++ b/man/build_reference.Rd
@@ -31,8 +31,8 @@ rapidly prototype. It is set to \code{FALSE} by \code{\link[=build_site]{build_s
 
 \item{run_dont_run}{Run examples that are surrounded in \\dontrun?}
 
-\item{seed}{Seed used to initialize so that random examples are
-reproducible.}
+\item{seed}{Seed used to initialize random number generation so that
+examples are reproducible.}
 
 \item{override}{An optional named list used to temporarily override
 values in \verb{_pkgdown.yml}}
diff --git a/man/build_site.Rd b/man/build_site.Rd
index cb56aedb00..7b5e80af7d 100644
--- a/man/build_site.Rd
+++ b/man/build_site.Rd
@@ -25,8 +25,8 @@ build_site(
 
 \item{run_dont_run}{Run examples that are surrounded in \\dontrun?}
 
-\item{seed}{Seed used to initialize so that random examples are
-reproducible.}
+\item{seed}{Seed used to initialize random number generation so that
+examples are reproducible.}
 
 \item{lazy}{If \code{TRUE}, will only rebuild articles and reference pages
 if the source is newer than the destination.}
diff --git a/vignettes/test/widgets.Rmd b/vignettes/test/widgets.Rmd
index aee3699602..f4200cc90d 100644
--- a/vignettes/test/widgets.Rmd
+++ b/vignettes/test/widgets.Rmd
@@ -15,7 +15,7 @@ Test spacing above widget.
 
 ```{r, echo=FALSE}
 # set seed for reproducible widget id
-if (requireNamespace("htmltools", quietly = TRUE)) {
+if (requireNamespace("htmlwidgets", quietly = TRUE)) {
   htmlwidgets::setWidgetIdSeed(42)
 }