check parameters of metadata utilities

ref #190

Author: wibeasley

R/metadata-utilities.R

@@ -52,17 +52,34 @@
 #'
 #' regex_named_captures(pattern=pattern_boxes, text=choices_2)
 #' }
+#'
+#' path_3         <- system.file(package="REDCapR", "test-data/project-simple/simple-metadata.csv")
+#' ds_metadata_3  <- read.csv(path_3, stringsAsFactors=FALSE)
+#' choices_3      <- ds_metadata_3[ds_metadata_3$field_name=="race", "select_choices_or_calculations"]
+#' regex_named_captures(pattern=pattern_boxes, text=choices_3)
 
 #' @export
 regex_named_captures <- function( pattern, text, perl=TRUE ) {
+
+  checkmate::assert_character(pattern, any.missing=F, min.chars=0L, len=1)
+  checkmate::assert_character(text   , any.missing=F, min.chars=0L, len=1)
+  checkmate::assert_logical(  perl   , any.missing=F)
+
   match <- gregexpr(pattern, text, perl=perl)[[1]]
   capture_names <- attr(match, "capture.names")
-  d <- as.data.frame(matrix(NA, nrow=length(attr(match, "match.length")), ncol=length(capture_names)))
+  d <- as.data.frame(matrix(
+    data  = NA_character_,
+    nrow  = length(attr(match, "match.length")),
+    ncol  = length(capture_names)
+  ))
   colnames(d) <- capture_names
 
+
   for( column_name in colnames(d) ) {
     d[[column_name]] <- mapply(
-      function (start, len) substr(text, start, start+len-1L),
+      function (start, len) {
+        substr(text, start, start+len-1L)
+      },
       attr(match, "capture.start" )[, column_name],
       attr(match, "capture.length")[, column_name]
     )
@@ -73,6 +90,8 @@ regex_named_captures <- function( pattern, text, perl=TRUE ) {
 #' @rdname metadata_utilities
 #' @export
 checkbox_choices <- function( select_choices ) {
+  checkmate::assert_character(select_choices, any.missing=F, len=1, min.chars=1)
+
   #The weird ranges are to avoid the pipe character; PCRE doesn't support character negation.
   pattern_checkboxes <- "(?<=\\A| \\| )(?<id>\\d{1,}), (?<label>[\x21-\x7B\x7D-\x7E ]{1,})(?= \\| |\\Z)"