Prettier for Ruby
@prettier/plugin-ruby
is a prettier plugin for the Ruby programming language and its ecosystem. prettier
is an opinionated code formatter that supports multiple languages and integrates with most editors. The idea is to eliminate discussions of style in code review and allow developers to get back to thinking about code design instead.
For example, the below code segment:
d=[30644250780,9003106878,
30636278846,66641217692,4501790980,
671_24_603036,131_61973916,66_606629_920,
30642677916,30643069058];a,s=[],$*[0]
s.each_byte{|b|a<<("%036b"%d[b.
chr.to_i]).scan(/\d{6}/)}
a.transpose.each{ |a|
a.join.each_byte{\
|i|print i==49?\
($*[1]||"#")\
:32.chr}
puts
}
when run through @prettier/plugin-ruby
will generate:
d = [
30_644_250_780,
9_003_106_878,
30_636_278_846,
66_641_217_692,
4_501_790_980,
671_24_603036,
131_61973916,
66_606629_920,
30_642_677_916,
30_643_069_058
]
a, s = [], $*[0]
s.each_byte { |b| a << ("%036b" % d[b.chr.to_i]).scan(/\d{6}/) }
a.transpose.each do |a|
a.join.each_byte { |i| print i == 49 ? ($*[1] || "#") : 32.chr }
puts
end
Getting started
The @prettier/plugin-ruby
plugin for prettier
is a small wrapper around the Syntax Tree gem that provides a Ruby formatter for prettier
. It does this by keeping a Ruby server running in that background that prettier
can communicate with when it needs to format a Ruby file. This means that in order to function, you will need to have both the requisite node
and ruby
dependencies installed. Because of this configuration, there are a couple of ways that you can get setup to use this plugin.
- If you're already using
prettier
in your project to format other files in your project and want to install this as a plugin, you can install it usingnpm
. - If you're not using
prettier
yet in your project, then we recommend using the Syntax Tree gem directly instead of using this plugin. - Note that this plugin also ships a gem named
prettier
which is a wrapper around theprettier
CLI and includes this plugin by default, but we no longer recommend its use. If you're using that gem, you should migrate to using Syntax Tree instead.
To run prettier
with the Ruby plugin as an npm
package, you're going to need ruby
(version 2.7
or newer) and node
(version 16
or newer).
If you're using the npm
CLI, then add the plugin by:
npm install --save-dev prettier @prettier/plugin-ruby
Or if you're using yarn
, then add the plugin by:
yarn add --dev prettier @prettier/plugin-ruby
You'll also need to add the necessary Ruby dependencies. You can do this by running:
gem install bundler prettier_print syntax_tree syntax_tree-haml syntax_tree-rbs
The prettier
executable is now installed and ready for use:
./node_modules/.bin/prettier --plugin=@prettier/plugin-ruby --write '**/*'
Using Prettier >= 3.0
You need to tell Prettier to use the plugin, add the following to your existing prettier configuration file.
{
"plugins": ["@prettier/plugin-ruby"]
}
Configuration
Below are the options (from src/plugin.js
) that @prettier/plugin-ruby
currently supports:
API Option | CLI Option | Default | Description |
---|---|---|---|
printWidth |
--print-width |
80 |
Same as in Prettier (see prettier docs). |
requirePragma |
--require-pragma |
false |
Same as in Prettier (see prettier docs). |
rubyExecutablePath |
"ruby" |
Allows you to configure your Ruby executable path. | |
rubyPlugins |
--ruby-plugins |
"" |
The comma-separated list of plugins to require. See Syntax Tree. |
rubySingleQuote |
--ruby-single-quote |
false |
Whether or not to default to single quotes for Ruby code. See Syntax Tree. |
tabWidth |
--tab-width |
2 |
Same as in Prettier (see prettier docs). |
trailingComma |
--trailing-comma |
es5 |
Almost same as in Prettier (see prettier docs). Will be on for any value except none . |
Any of these can be added to your existing prettier configuration file. For example:
{
"tabWidth": 4
}
Or, they can be passed to prettier
as arguments:
bundle exec rbprettier --tab-width 4 --write '**/*'
Ignoring code
Sometimes you want to leave your formatting in place and have prettier
not format it, but continue to format the rest of the file. prettier
has the ability to do this with prettier-ignore
comments, but because the underlying formatter for this plugin is Syntax Tree, you instead would use a stree-ignore
comment.
Usage with RuboCop
RuboCop and Prettier for Ruby serve different purposes, but there is overlap with some of RuboCop's functionality. Prettier provides a RuboCop configuration file to disable the rules which would clash. To enable this file, add the following configuration at the top of your project's .rubocop.yml
:
inherit_from:
- node_modules/@prettier/plugin-ruby/rubocop.yml
Usage with an editor
For supported editor integrations, you should follow the instructions for installing the integration, then install the npm version of this plugin as a development dependency of your project. For most integrations, that should be sufficient. For convenience, the instructions for integrating with VSCode are used as an example below:
- Install the Prettier - Code Formatter extension.
- Add the npm
@prettier/plugin-ruby
package to your project as described above. - Configure in your
settings.json
(formatOnSave
is optional):
{
"[ruby]": {
"editor.defaultFormatter": "esbenp.prettier-vscode",
"editor.formatOnSave": true
}
}
Refer to this issue if you're having difficulties.
Contributing
Thanks so much for your interest in contributing! You can contribute in many ways, including:
- Contributing code to fix any bugs on GitHub.
- Reporting issues on GitHub.
- Supporting
prettier/plugin-ruby
on OpenCollective. Your organization's logo will show up here with a link to your website.
License
The package is available as open source under the terms of the MIT License.