RSpec

opal-rspec allows opal to use rspec for running specs in javascript environments. It comes with built-in support for running rspec with standard web browser formatters. Also, async spec examples are supported to reflect browser usage of ruby applications.

describe User do
 it "can be created with a name" do
 expect(User.new).to_not be_persisted
 end
end

Installation

Add the opal-rspec gem to your Gemfile:

# Gemfile
gem 'opal'
gem 'opal-rspec'

Running specs

In a Browser

opal-rspec can use sprockets to build and serve specs over a simple rack server. Add the following to a config.ru file:

# config.ru
require 'bundler'
Bundler.require
sprockets_env = Opal::RSpec::SprocketsEnvironment.new
run Opal::Server.new(sprockets: sprockets_env) { |s|
 s.main = 'opal/rspec/sprockets_runner'
 s.append_path 'spec'
 s.debug = false
}

Then run the rack server bundle exec rackup and visit http://localhost:9292 in any web browser.

Async examples

opal-rspec adds support for async specs to rspec. These specs are defined using #async instead of #it:

describe MyClass do
 # normal example
 it 'does something' do
 expect(:foo).to eq(:foo)
 end
 # async example
 async 'does something else, too' do
 # ...
 end
end

This just marks the example as running async. To actually handle the async result, you also need to use a run_async call inside some future handler:

async 'HTTP requests should work' do
 HTTP.get('/users/1.json') do |res|
 run_async {
 expect(res).to be_ok
 }
 end
end

The block passed to run_async informs the runner that this spec is finished so it can move on. Any failures/expectations run inside this block will be run in the context of the example.