My awesome RSpec hacks

my_awesome_rspec_hacks.rb

## Context + metadata
shared_context 'Logged as a user', role: true do
  let(:user) { |example| create :user, example.metadata[:role] }
  before { login_as user }
end

scenario "Login as a client", role: :client
scenario "Login as a customer", role: :customer
scenario "Login as an admin", role: :admin


## Running chrome headless by default and chrome on demand
Capybara.register_driver :headless_chrome do |app|
  capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
    chromeOptions: { args: %w(headless disable-gpu window-size=1200,720) }
  )
  Capybara::Selenium::Driver.new app, browser: :chrome, desired_capabilities: capabilities
end

Capybara.register_driver :chrome do |app|
  Capybara::Selenium::Driver.new app, browser: :chrome
end

Capybara.default_driver = ENV['CHROME'] ? :chrome : :headless_chrome
# A common quite mode
`rspec`
# A debug mode
`CHROME=1 rspec`


## API specs sugar methods
module ApiSpecHelpers
  # easy response navigation
  def resp_json(*keys, &block)
    payload = keys.reduce(JSON.parse(response.body)) { |acc, k| acc[k] }
    yield payload if block_given?
    payload
  end
  # a universal method to test json API
  def fetch(url, options = {})
    params = options.fetch(:params, {})
    headers = options.fetch(:headers, {})
    case options.fetch(:method, :get)
    when :get then get(url, params: params, headers: headers)
    when :post then post(url, params: params.to_json, headers: { 'content-type' => 'application/json' }.merge(headers))
    when :put then put(url, params: params.to_json, headers: { 'content-type' => 'application/json' }.merge(headers))
    else
      raise NotImplementedError, "fetch doesn't support #{options.fetch(:method)}"
    end
  end
end
      
config.include(ApiSpecHelpers, type: :request)
      
it 'fetches a resent posts' do
  expect(fetch('/api/posts')).to eq(200)
  resp_json('data', 0, 'categories') do |categories|
    expect(categories).to include('Fun RSpec')
    expect(categories).not_to include('Boring JUnit')
  end
end
  
it 'publish a new post' do
  payload = { data: { name: "A new gist post", description: "A post in a gist way. Less words, more code!" } }
  expect(fetch('/api/posts', { method: 'POST', body: payload })).to eq(201)
  expect(resp_json('data', 'id')).to be_present
end


## Testing a different attribute sets
RSpec.describe 'A different behaviours' do
  let(:params) { {} }
  let(:form)   { PostForm.new(params) }
  subject(:publish_post) { form.save }
  
  it 'rejects a post by missing fields' do
    expect(publish_post).to be_falsy
    expect(form.errors[:name]).to eq(["can't be blank"])
  end
  
  it 'rejects a post by not accepting GDPR' do
    params.merge!(name: '10 reasons why mutation is awesome', description: 'Yes, it is. But use it carefully')
    expect(publish_post).to be_falsy
    expect(form.errors[:base]).to include("Please accept private policy first")
    expect(form.errors[:name]).to eq(["can't be blank"])
  end
  
  it 'finally published a post' do
    params.merge!(name: 'Coffee is a good start of a day', description: 'Some people say...', accept_policy: true)
    expect(publish_post).to be_truthy
    expect(form.record).to be_persisted
  end
end