gem ripper tags

fast and accurate ctags generator on gem install

Ruby

RubyGems Automatic Ctags Generator

If you do like Vim and Ctags like I or Tim Pope do, you maybe appreciate
automatic generation of ctags for each installed gem. This small project is
based on Tim’s gem-ctags, but the main difference is it does not use
Exuberant Ctags.

Upstream site is at: https://github.com/lzap/gem-ripper-tags

Usage

Install the thing (only Ruby 1.9+):

gem install gem-ripper-tags

Then generate tags for all already installed gems:

gem ripper_tags

Anytime you install a gem now, tags will be automatically created.

gem instal some_gem ...

If you’re using RVM, I recommend extending your global gemset by adding
gem-ripper-tags to ~/.rvm/gemsets/global.gems. Put it at the top so the
gems below it will be indexed.

You can use the gem even with 1.8 gemsets, but since Ruby 1.8 is not
supported, it will (silently) not register the gem hook.

Motivation

Why would you care about not using ctags in the first place? Ctags is a great
project and it does support many (like 50) languages. But Ruby support is very
weak, the parser is not in good condition and it has not been changed 4 years
now.

Ctags doesn’t deal with: module A::B
Ctags doesn’t tag (at least some of) the operator methods like ==
Ctags doesn’t support qualified tags, -type=+
Ctags doesn’t output tags for constants or attributes.

Unfortunately all the others (I found 2) Ruby ctags generators are either
outdated (no Ruby 1.9+ support) or very slow. This project makes use of
ripper-tags that leverages built-in Ruby parser API called Ripper. It is
fast and it works as expected.

Regeneration

If you want to regenerate all tagfiles from scratch, use:

gem ripper_tags --reindex

Emacs support

To support Emacs, you need two steps. First, reindex everything with Emacs
enabled:

gem ripper_tags --reindex --emacs

And make sure this environment variable is set to all shells where you use
“gem install” command so new gems are generated with Emacs TAGS files.

RIPPER_TAGS_EMACS=1

Vim Tips

To easily edit a gem with your current working directory set to the
gem’s root, install gem-browse.

If you have rake.vim installed (which, by the way, is a misleading
name), Vim will already know where to look for the tags file when
editing a gem.

If you have bundler.vim installed, Vim will be aware of all tags
files from all gems in your bundle.

If you want to get crazy, add this to your vimrc to get Vim to search
all gems in your current RVM gemset (requires pathogen.vim):

autocmd FileType ruby let &l:tags = pathogen#legacyjoin(pathogen#uniq(
      \ pathogen#split(&tags) +
      \ map(split($GEM_PATH,':'),'v:val."/gems/*/tags"')))

Tim Pope doesn’t like to get crazy. 😉