From 4eaff479860dba6ebd840c0c6c242454d0117823 Mon Sep 17 00:00:00 2001
From: Christophe Dervieux <christophe.dervieux@gmail.com>
Date: Mon, 30 Nov 2020 18:38:13 +0100
Subject: [PATCH] handle new prefix in fontawesome 5

---
 R/html_dependencies.R |  6 ++++--
 R/html_document.R     | 13 ++++++++++++-
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/R/html_dependencies.R b/R/html_dependencies.R
index c51f8c397e..23892ca7f6 100644
--- a/R/html_dependencies.R
+++ b/R/html_dependencies.R
@@ -141,7 +141,7 @@ navbar_icon_dependencies <- function(navbar) {
   source <- read_utf8(navbar)
 
   # find icon references
-  res <- regexec('<(span|i) +class *= *("|\') *(fa fa|ion ion)-', source)
+  res <- regexec('<(span|i) +class *= *("|\') *(fa\\w fa|ion ion)-', source)
   matches <- regmatches(source, res)
   libs <- c()
   for (match in matches) {
@@ -151,7 +151,9 @@ navbar_icon_dependencies <- function(navbar) {
   libs <- unique(libs)
 
   # return their dependencies
-  html_dependencies_fonts("fa fa" %in% libs, "ion ion" %in% libs)
+  any_fa <- any(grepl("fa\\w fa", libs))
+  any_ion <- any(grepl("ion ion", libs))
+  html_dependencies_fonts(any_fa, any_ion)
 }
 
 # utility function to return a list of font dependencies based
diff --git a/R/html_document.R b/R/html_document.R
index 2c23dbf2b4..7c40d6b6f8 100644
--- a/R/html_document.R
+++ b/R/html_document.R
@@ -646,7 +646,18 @@ navbar_link_text <- function(x, ...) {
       iconset <- split[[1]][[1]]
     else
       iconset <- ""
-    tagList(tags$span(class = paste(iconset, x$icon)), " ", x$text, ...)
+    # check if a full class is passed for fontawesome
+    # use default 'fas' otherwise
+    # https://github.com/rstudio/rmarkdown/issues/1554
+    class = if (grepl("^fa\\w fa", iconset)) {
+      x$icon
+    } else if (iconset == "fa") {
+      paste("fas", x$icon)
+    } else {
+      # should be other than FontAwesome
+      paste(iconset, x$icon)
+    }
+    tagList(tags$span(class = class), " ", x$text, ...)
   }
   else
     tagList(x$text, ...)