The command
rdoc --dry-run --root=lib --format=darkfish --op=rdocs
aborts with
No such file or directory @ rb_sysopen - /home/FISRONA/gitwrk/vp5/rdocs/js/search_index.js
unless directory rdocs already contains files from a previous generation. It seems that --dry-run doesnt anticipate, that these intermediate directories will be generated in time.
Using rdoc 4.2.0 (Cygwin)