RSpec

Rspec Config

1. gem install rspec

group :development, :test do
  gem 'byebug', '~> 9.1'
  gem 'factory_girl_rails', '~> 4.9'
  gem 'launchy', '~> 2.4', '>= 2.4.3'
  gem 'pry-rails', '~> 0.3.6'
  gem 'rspec-rails', '~> 3.0'
  gem 'spring', '~> 2.0', '>= 2.0.2'
  gem 'web-console', '~> 3.5', '>= 3.5.1'
end

group :test do
  gem 'capybara', '~> 2.15', '>= 2.15.4'
  gem 'database_cleaner', '~> 1.6', '>= 1.6.1'
  gem 'faker', '~> 1.8', '>= 1.8.4'
  gem 'rspec', '~> 3.7'
  gem 'shoulda-matchers', '~> 3.1', '>= 3.1.2'
end

1.1  gem 'rspec-rails' in the dev group so it will create spec once we create the controller via rails g model 

2. rspec --init..

3.rails generate rspec:model user

4. rails generate rspec:controller User

5. copy the below to spec_helper:

ENV["RAILS_ENV"] ||= 'test'
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'

6.create test db:

.7.rake db:test:prepare

8.databasecleaner is a tool used to clean db when u need to clear the db:

in spec_helper:
require 'database_cleaner'
DatabaseCleaner.strategy = :truncation, { :only => %w[users] }
in array give name u need.
then DatabaseCleaner.clean whenever you need to clean user
the common point is at after RSpec.config or at  before(:all) do last

in psql manually create test_db and do rake db:migrate RAILS_ENV=test
 

8. gem install factory girl and do the below line to config page in spec_helper

config.before(:all) do
  FactoryGirl.reload
end

9. to clear table data in test db:
spec_helper:

config.after :all do
    ActiveRecord::Base.subclasses.each(&:delete_all)
  end

10.to view test db:  rails c test

if below error 
undefined method `sign_in' for #<RSpec::Core:
then add below line to spec_helper:
config.include Devise::TestHelpers, type: :controller