Setting up Ruby for VSCode

Feb 4, 2021

Here is a little guide to setting up IntelliSense and auto-completion on VSCode for Ruby quickly. Requirements

Might seem a bit obvious, but you need the following in your computer:

VSCode

Ruby

What will be installed?

Rubocop

From its page: The Ruby Linter/Formatter that Serves and Protects. It’s just that. A linter and formatter that takes rules from a configuration file ad applies them to Ruby files.

Airbnb Ruby style guide

I use this one because its widespread and sane. I also use their JavaScript style guide.

Solargraph

Solargraph is a Ruby gem that provides intellisense features through Microsoft’s language server protocol. It can also lint and format code, but I find Rubocop better for that task.

Ruby extension for VSCode

Solargraph extension for VSCode

What is IntelliSense?

In a nutshell, IntelliSense provides autocomplete for your code (names for methods, classes, etc) and also inline documentation. For example, if you want to apply a Ruby method on an array, it will present you with all the methods for arrays as you type. It’s very useful and can speed up coding a lot.

The installation

Gem installation

In a terminal, enter this command:

gem install solargraph rubocop-airbnb

It installs Solargraph and the Airbnb extension for Rubocop, which in turn installs Rubocop. It’s better to install Rubocop in this way only because VSCode reports of conflicting versions in the system otherwise. Extension installation

Then, we install the VSCode extensions. You could look for ruby.rebornix and castwide.solargraph on the extension marketplace inside VSCode or copy/paste this commands on the command palette (usually Ctrl/Cmd + Shift + P or F1.)

ext install rebornix.Ruby
ext install castwide.solargraph

Note: remember to remove the > that appears on the command palette.

Configurations

System configuration

Rubocop will take a global configuration file on your home directory. In Linux the path is /home/<your-username> and on Windows it should be C:\Users\<your-username>.

The filename is .rubocop.yml and it must contain these two lines.

require:
- rubocop-airbnb

VSCode settings

In VSCode, we need to edit settings.json. Copy and paste these lines and edit them with your values.

"ruby.interpreter.commandPath": "path/to/ruby",
"ruby.useLanguageServer": true,
"ruby.useBundler": true,

"solargraph.commandPath": "path/to/solargraph",
"solargraph.formatting": true,
"solargraph.diagnostics": true,
"[ruby]": { "editor.defaultFormatter": "castwide.solargraph" },

To find the correct paths to Ruby and Solargraph, enter these commands depending on your OS.

Linux

which ruby which solargraph
Windows
where ruby where solargraph

And that’s it. With that, VSCode is now a great environment for writing Ruby code.