CircleCI Simplecov artifact (https://circleci.com/docs/code-coverage)

.simplecov

SimpleCov.coverage_dir('tmp/coverage')

# save to CircleCI's artifacts directory if we're on CircleCI
# see https://circleci.com/docs/code-coverage
if ENV['CIRCLE_ARTIFACTS']
  dir = File.join(ENV['CIRCLE_ARTIFACTS'], 'coverage')
  SimpleCov.coverage_dir(dir)
end

require 'simplecov-csv'
require 'simplecov-cobertura'
require 'simplecov-json'
require 'simplecov-text'

SimpleCov.formatters = [
  SimpleCov::Formatter::HTMLFormatter,
  SimpleCov::Formatter::CSVFormatter,
  SimpleCov::Formatter::CoberturaFormatter,
  SimpleCov::Formatter::JSONFormatter,
  SimpleCov::Formatter::TextFormatter
]

SimpleCov.start 'rails'

Gemfile

group :test do
  gem 'simplecov', require: false
  gem 'simplecov-cobertura', require: false
  gem 'simplecov-csv', require: false
  gem 'simplecov-json', require: false
  gem 'simplecov-text', require: false
end

spec-rails_helper.rb

# This file is copied to spec/ when you run 'rails generate rspec:install'
ENV['RAILS_ENV'] ||= 'test'

require File.expand_path('../../config/environment', __FILE__)
# Prevent database truncation if the environment is production
abort("The Rails environment is running in production mode!") if Rails.env.production?
require 'spec_helper'
require 'rspec/rails'

Dir[Rails.root.join("spec/support/**/*.rb")].each { |f| require f }

# Checks for pending migrations before tests are run.
# If you are not using ActiveRecord, you can remove this line.
ActiveRecord::Migration.maintain_test_schema!

RSpec.configure do |config|
  # The different available types are documented in the features, such as in
  # https://relishapp.com/rspec/rspec-rails/docs
  config.infer_spec_type_from_file_location!
end