Gemfile

# Add poltergeist gem to Gemfile, in :test group,
# then run `bundle` to install
group :test do
  ...
  gem 'poltergeist'
  ...
end

INSTALL_PHANTOMJS.md

JavaScript Testing with PhantomJS

PhantomJS is required to run JavaScript-dependent specs.

Install PhantomJS on Ubuntu

SSH into your Vagrant Virtual Machine if you're using one, then run the following commands to install PhantomJS:

curl -sL https://deb.nodesource.com/setup | sudo bash -
sudo apt-get install nodejs
npm install -g phantomjs

Install PhantomJS on Mac OS X

Only do this if you're not using Vagrant:

Follow installation instructions for Mac OS X: http://phantomjs.org/download.html

spec->features->sample_spec.rb

# For any specs that require JS, in a describe block (top-level or nested), 
# specify the option `js: true`

describe "Searching widgets", js: true do
  
  it "shows 10 results" do
    ... 
  end
  
end

spec->rails_helper.rb

# 1. Add 'require "capybara/poltergeist" to rails_helper.rb below
# existing 'require "capybara/rspec" line.
# AND
# 2. Set Capybara's JavaScript driver to be :poltergeist

ENV["RAILS_ENV"] ||= 'test'
require 'spec_helper'
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'
require "capybara/rails"
require "capybara/rspec"
require "capybara/poltergeist" # Add this line to require poltergeist

# Specs flagged with `js: true` will use Capybara's JS driver. Set
# that JS driver to :poltergeist
Capybara.javascript_driver = :poltergeist

# We want to load config from spec/support/database_cleaner.rb, so ensure this line is uncommented
# in your rails_helper.rb
Dir[Rails.root.join("spec/support/**/*.rb")].each { |f| require f }

...

RSpec.configure do |config|
  ...
  # IMPORTANT! Ensure that config.use_transactional_fixtures is false 
  config.use_transactional_fixtures = false
  ...
end

spec->support->database_cleaner.rb

RSpec.configure do |config|  
  config.before(:suite) do
    DatabaseCleaner.clean_with(:truncation)
  end

  config.before(:each) do
    DatabaseCleaner.strategy = :transaction
  end

  # Configure DatabaseCleaner to use truncation strategy with
  # JavaScript (js: true) specs.
  #
  # We want to ensure we're not using transactions as the work they do is
  # isolated to one database connection. One database connection is used by
  # the specs, and another, separate database connection is 
  # used by the app server phantomjs interacts with. Truncation, when *not*
  # inside a transaction, affects all database connections, so truncation is
  # what we need!
  # http://www.railsonmaui.com/tips/rails/capybara-phantomjs-poltergeist-rspec-rails-tips.html
  # http://devblog.avdi.org/2012/08/31/configuring-database_cleaner-with-rails-rspec-capybara-and-selenium/ 
  config.before(:each, js: true) do
    DatabaseCleaner.strategy = :truncation
  end
 
  config.before(:each) do
    DatabaseCleaner.start
  end
 
  config.after(:each) do
    DatabaseCleaner.clean
  end
end