Switch to code @yihui wrote in the PR review (after testing it)

R/hugo.R

@@ -190,20 +190,12 @@ install_theme = function(theme, theme_example = FALSE, update_config = TRUE, for
 #'   (e.g. a post or a page).
 new_content = function(path, kind = 'default', open = interactive()) {
   if (missing(kind)) kind = default_kind(path)
-  ## Hugo doesn't work well with non .md file terminations
-  ## So for those cases we will temporarely change the file termination
-  ## to md, run hugo, then change back the file termination.
-  path_temp = gsub(paste0(tools::file_ext(path), '$'), 'md', path)
-  file.copy(path, path_temp)
-  if(path_temp != path) on.exit(unlink(path_temp), add = TRUE)
-  hugo_cmd(c('new', shQuote(path_temp), c('-k', kind)))
-
-  file_temp = content_file(path_temp)
-  if(path_temp != path) on.exit(unlink(file_temp), add = TRUE)
-  ## If we do this after fixing the file termination it doesn't work
-  hugo_toYAML(file_temp)
-  file = gsub('md$', tools::file_ext(path), file_temp)
-  file.copy(file_temp, file)
+  path2 = with_ext(path, '.md')
+  file  = content_file(path)
+  file2 = content_file(path2)
+  hugo_cmd(c('new', shQuote(path2), c('-k', kind)))
+  hugo_toYAML(file2)
+  file.rename(file2, file)
   if (open) open_file(file)
   file
 }