need local chunk options in hook_purl() to check if user has set erro…

…r=TRUE for that chunk

also close #2338

NEWS.md

@@ -18,7 +18,7 @@
 
 - Unbalanced chunk delimiters (fences) in R Markdown documents are strictly prohibited now.
 
-- For code chunks with `error = TRUE`, `purl()` and `hook_purl()` will wrap the code in `try({...})` (thanks, @jeroen, #2368).
+- For code chunks with `error = TRUE`, `purl()` and `hook_purl()` will wrap the code in `try({...})` (thanks, @bastistician #2338, @jeroen #2368).
 
 ## MINOR CHANGES
 

R/hooks-extra.R

@@ -146,7 +146,10 @@ hook_purl = function(before, options, ...) {
     .knitEnv$tangle.params = NULL
   }
 
-  code = tangle_mask(options$code, options$eval, options$error)
+  # `options` contains merged chunk options, but we need to check if
+  # `error=TRUE` in local chunk options, so retrieve options from knit_code
+  error = attr(knit_code$get(options$label), 'chunk_opts')[['error']]
+  code = tangle_mask(options$code, options$eval, error)
   if (is.character(output)) {
     code = c(
       if (file.exists(output)) read_utf8(output),