format_num(): added na_label arg

Author: pvictor

NEWS.md

@@ -2,6 +2,7 @@ apexcharter 0.4.5
 ==================
 
 * Updated ApexCharts.js to 4.7.0 (see https://github.com/apexcharts/apexcharts.js/releases).
+* `format_num()`: added `na_label` argument to specify how to represent missing values.
 
 
 

R/format.R

@@ -7,22 +7,32 @@
 #' @param suffix Character string to append after formatted value.
 #' @param locale Localization to use, for example \code{"fr-FR"} for french,
 #'  see possible values here: \url{https://github.com/d3/d3-format/tree/master/locale}.
+#' @param na_label The label to use when value is `NA`.
 #'
 #' @return a \code{JS} function
 #' @export
 #'
 #' @importFrom htmlwidgets JS
 #'
 #' @example examples/format.R
-format_num <- function(format, prefix = "", suffix = "", locale = "en-US") {
+format_num <- function(format,
+                       prefix = "",
+                       suffix = "",
+                       locale = "en-US",
+                       na_label = "-") {
   check_locale_d3(locale)
   path <- system.file(file.path("d3-format-locale", paste0(locale, ".json")), package = "apexcharter")
-  if (path != "") {
+  if (!identical(path, "")) {
     locale <- paste(readLines(con = path, encoding = "UTF-8"), collapse = "")
   }
+  if (is.character(na_label) && length(na_label) == 1) {
+    na_label <- sprintf("if (value === null) return '%s';", na_label)
+  } else {
+    na_label <- ""
+  }
   JS(sprintf(
-    "function(value) {var locale = formatLocale(JSON.parse('%s')); return '%s' + locale.format('%s')(value) + '%s';}",
-    locale, prefix, format, suffix
+    "function(value) {%s var locale = formatLocale(JSON.parse('%s')); return '%s' + locale.format('%s')(value) + '%s';}",
+    na_label, locale, prefix, format, suffix
   ))
 }