Ripgrep

counsel-rg

Lately, due to working with a large code base, I've grown more and more fond of counsel-rg. It's an Elisp wrapper around ripgrep - a relatively new recursive grep tool that aims to be faster than the competition (ag, git grep, pt, ack etc).

Besides being really fast, rg also has some really nice command switches. One such switch is especially useful for Emacs:

-M, --max-columns NUM : Don't print lines longer than this limit in bytes. Longer lines are omitted, and only the number of matches in that line is printed.

The -M switch is useful twofold:

• Emacs is slow when dealing with long lines (by long I mean thousands of chars per line)
• Emacs is slow at accepting a huge amount of output from a process

For each character you add to your input, counsel-rg starts a new shell command to recalculate the matches with the new input. This means that in order to avoid keyboard lag there's only about 0.1 seconds available for both:

1. Running the shell command.
2. Accepting output from the shell command.

So I'm quite happy that rg speeds up both steps. Less time spent on these steps provides for much smoother searching.

counsel-grep-or-swiper

I also work with large log files, one file at a time. For a long time, I've used counsel-grep-or-swiper as my main search command:

(global-set-key (kbd "C-s") 'counsel-grep-or-swiper)

But for a 40Mb log file with really long lines counsel-grep-or-swiper started to lag a bit. I tried counsel-rg, and it was actually faster than grep, although it was searching the whole directory. So I thought, why not use rg instead of grep? The switch is actually really easy and required only a simple user customization:

(setq counsel-grep-base-command
 "rg -i -M 120 --no-heading --line-number --color never '%s' %s")

Outro

If you haven't tried ripgrep so far, I suggest you give it a go. Happy hacking!

And if you're a C hacker and have some free time on your hands, why not look at the long lines and the process output issues in Emacs? I'd be very grateful:)