Add replace_leading_whitespace function

R/replace_leading_whitespace.R

@@ -0,0 +1,28 @@
+#' Reformat strings with leading whitespace for HTML
+#'
+#' @param x Target string
+#' @param tab_width Number of spaces to compensate for tabs
+#'
+#' @return String with   replaced for leading whitespace
+#' @export
+#'
+#' @examples
+#' x <- c(" Hello there", "  Goodbye Friend ",  "\tNice to meet you", "  \t What are you up to? \t \t ")
+#' replace_leading_whitespace(x)
+#'
+#' replace_leading_whitespace(x, tab=2)
+#'
+replace_leading_whitespace <- function(x, tab_width=4) {
+  # Pull out the leading whitespace chunk
+  leading_spaces <- stringr::str_match(x, "^([ \\t])+")[,1]
+  # Count spaces and tabs, factor in tab width
+  spaces <- stringr::str_count(leading_spaces, pattern = " ")
+  tabs <- stringr::str_count(leading_spaces, pattern = "\\t") * tab_width
+  leading_length <- as.integer(spaces + tabs)
+
+  # Build the &nbsp; string and combine with the trimmed string
+  nbsp_string <- map_chr(leading_length, \(.x) paste(rep("&nbsp;", .x), collapse=""))
+  minus_whitespace <- stringr::str_trim(x, side=left)
+  paste(nbsp_string, minus_whitespace, sep="")
+}
+