TLDR; Click here to jump to the end if you just want fast Ruby tests in VS Code.

I should have done this years ago, if only I knew.

I’ve been doing a lot more JavaScript recently, one of the things I’ve fallen in love with is the speed of testing and the interface provided in VS Code shown below.

I spend at least as much time if not more in Ruby and am a strong believer in optimising my workflow especially when it clearly pays dividends.

After a little bit of research, I find the Ruby Test Explorer extension for VS Code providing a similar UI to the one that VS Code Jest provides.

I start using this and within a day become very frustrated about how slow it is and find myself reverting back to the terminal.

Today I found myself doing a bit of housekeeping and increasing test coverage in a few areas of TechTalks, that want for instant feedback returns so I investigate further.

Running RSpec with Spring

How have I never considered this? Also, why is not the default?

Simply adding spring-commands-rspec reduced my single file tests from 4.5s to 0.4s a whopping 91.1% decrease in execution time.

Setup

1. Install VS Code Ruby Test Explorer extension.

2. Add the spring-commands-rspec gem to your project

    gem 'spring-commands-rspec', group: :development, require: false
   

3. Generate the RSpec binstub

    $ bundle exec spring binstub rspec
   

4. Configure Ruby Test Explorer to use Spring.

   Ensure the following is set in your workspace or user settings. Mine is within my project at ./.vscode/settings.json.

    {
      "rubyTestExplorer.rspecCommand": "bundle exec spring rspec"
    }
   

Result

Before	After