RSpec + Rails Without rspec-rails @ RoRoSyd November 2015

Transcript

1. @JonRowe
   RSPEC + RAILS
   Without rspec-rails
   

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2. History
   2179 commits, 194 people since 2009
   
   Thin wrapper over Rails helpers
   

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3. Why
   Rails is integrated
   
   Rails is opinionated
   
   Rails is slow(er) to boot
   

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4. How
   Load components of Rails as needed
   
   Change how we test
   

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5. How
   PORO Specs
   
   Model Specs
   
   Controller Specs
   
   Acceptance / Feature Specs
   
   Other Specs
   

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6. Autoloading
   To autoload or not to autoload.
   
   `require` works… but can be painful
   
   Rails constant lookup can be surprising
   

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7. require 'bundler/setup'
   gem_paths =
   Dir[
   File.join Bundler.bundle_path,
   “/gems/**/lib”
   ]
   app_paths =
   Dir[
   File.expand_path(‘./lib/**'),
   File.expand_path(‘./app/**')
   ]
   (gem_paths + app_paths).each do |path|
   ActiveSupport::Dependencies
   .autoload_paths << File.expand_path(path)
   end
   ActiveSupport::Dependencies.hook!
   

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8. PORO Specs
   Plain old Ruby specs
   
   No change!
   

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9. Model Specs
   Need to load the database beforehand
   
   Don’t use `describe Model`
   

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10. module Support::Database
    def self.setup!
    return true if defined?(@connection)
    require ‘yaml’; require ‘active_record'
    config = YAML.load(ERB.new(
    IO.read(‘config/database.yml')
    ).result)
    @connection = ActiveRecord::Base
    .establish_connection(config[‘test'])
    ActiveRecord::Base
    .raise_in_transactional_callbacks = true
    true
    end
    end
    RSpec.configuration.before :context, :db do
    Support::Database.setup!
    end
    

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11. RSpec.describe 'MyModel', :db do
    let(:models) do
    (1..6).map { |i| MyModel.create! hidden: false }
    end
    describe '.active' do
    it 'returns all active models' do
    models[0..2].each do |model|
    model.update_attributes! hidden: tru
    end
    expect(
    MyModel.active
    ).to match_array models[3..-1]
    end
    end
    end
    

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12. # For verified doubles with ActiveRecord
    ::RSpec::Mocks.configuration
    .when_declaring_verifying_double do |possible|
    target = possible.target
    if target.respond_to?(:define_attribute_methods)
    possible.target.define_attribute_methods
    end
    end
    

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13. Controller Specs
    Don’t
    

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14. Controller Specs
    

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15. Controller Specs
    Controller specs are already fullstack
    
    Too hard to isolate them
    
    Refactor logic to services and test or…
    
    Write acceptance tests
    

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16. Acceptance Specs
    Are still (as slow as) Rails
    
    Partition from your suite
    

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17. require 'capybara/dsl'
    RSpec.configure do |config|
    config.include Capybara::DSL, :app
    config.before :context, :app do
    unless Capybara.app
    require ‘config/environment.rb’
    Capybara.app = Rails.application
    end
    Capybara.asset_host =
    "http://localhost:#{ENV['PORT'] || '8080'}"
    end
    config.after :example, :app do
    Capybara.reset_sessions!
    end
    end
    

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18. RSpec.describe 'Downloading a report', :app, :db do
    include Support::AdminHelper
    before do
    sign_in_as a_valid_admin
    end
    context 'when statistics are present' do
    it 'produces a csv' do
    visit "/admin"
    click_link 'Download CSV'
    expect {
    CSV.parse body
    }.to_not raise_error CSV::ParseError
    end
    end
    end
    

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19. RSpec.configure do |config|
    config.register_ordering :global do |examples|
    acceptance, unit = examples.partition do |ex|
    ex.metadata[:acceptance]
    end
    unit.shuffle + acceptance.shuffle
    end
    end
    

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20. Other
    Services / Presenters / Forms / ETC
    
    As long as they’re PORO(ish), work fine
    
    Mailers work with `email_spec`
    

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21. Other
    View / Request / Etc
    
    Not SRP, write acceptance specs or…
    
    Use `rspec-rails`
    
    

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22. THANKS
    @JONROWE
    

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23. CODE
    https://gist.github.com/JonRowe/867423bab8201b1f852b
    

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