return NULL instead of character(0) if input is NULL and dir = TRUE (#…

…950)
yihui · Apr 12, 2015 · efc40eb · efc40eb
1 parent 2e2a853
commit efc40eb
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/R/utils.R b/R/utils.R
@@ -646,6 +646,7 @@ is_windows = function() .Platform$OS.type == 'windows'
 current_input = function(dir = FALSE) {
   input = knit_concord$get('infile')
   outwd = opts_knit$get('output.dir')
+  if (is.null(input)) return()
   if (dir) {
     if (is.null(outwd)) {
       warning('Cannot determine the directory of the input document')