--file with empty file differs in behavior from grep

[mqudsi]

What version of ripgrep are you using?

0.8.1

What operating system are you using ripgrep on?

Linux/WSL

Describe your question, feature request, or bug.

From man grep:

-f FILE, --file=FILE
Obtain patterns from FILE, one per line. If this option is used multiple times or is combined with the -e (--regexp) option, search for all patterns given. The empty file contains zero patterns, and therefore matches nothing.

rg's behavior here is to treat an empty file as matching everything instead:

touch empty.txt
rg -l -f empty.txt
# prints all files

See also #783

[BurntSushi]

I don't understand what your goal is here. ripgrep differs from grep in many ways. Are you asking for better docs? A change in behavior?

[mqudsi]

Sorry, I should have been clearer. I was requesting that the same handling of an empty file passed to -f be used. The logic is that rg may be programmatically invoked against a generated matches.txt, in which case there is value in treating an empty file as not matching anything.

[BurntSushi]

OK, I agree. I had a chance to review #783 as well, and I agree that ripgrep should probably be consistent with grep here.

[mqudsi]

Thanks, much appreciated!

[mqudsi]

Thanks!