initial-test-data

The initial-test-data is a tool to create a text fixture for Rails applications.

Overview

Although the Rails itself has a standard mechanism to initialize the database in the test environment (ActiveRecord::FixtureSet), it is rather cumbersome to construct a real (often complicated) data structure from YAML files.

The initial-test-data provides a way to create a test fixture using Active Record, Factory Girl, etc.

It also offers utility methods called store and fetch to register and access the initialized data.

Installation

Add the following line to Gemfile:

gem 'initial-test-data', group: :test

Run bin/bundle install on the terminal.

Configuration of test framework

MiniTest

Edit test/test_helper.rb like this:

ENV['RAILS_ENV'] ||= 'test'
require File.expand_path('../../config/environment', __FILE__)
require 'rails/test_help'
require 'initial-test-data/factory_girl' # If you use the Factory Girl

InitialTestData.import

class ActiveSupport::TestCase
  include InitialTestData::Utilities

  # (snip)
end

Note that the default value of the first argument of import method is 'test', so you can omit it when your test scripts are located in the test directory.

RSpec

Edit spec/rails_helper.rb like this:

ENV["RAILS_ENV"] ||= 'test'
require 'spec_helper'
require File.expand_path("../../config/environment", __FILE__)
require 'rspec/rails'
require 'initial-test-data/factory_girl' # If you use the Factory Girl

RSpec.configure do |config|
  config.include InitialTestData::Utilities

  config.before(:suite) do
    InitialTestData.import('spec')
  end
end

Usage

Synopsis

• Create initial_data subdirectory in the test or spec directory.
• Put any ruby scripts on this file.
• Run your test suite.

Caching data

The initial-test-data generates the md5 digest of all ruby scripts in the initial_data directory and app/models directory, then stores it to the _initial_data_digest table of the test database.

When the generated md5 digest is equal to the previously stored value, data initializing process will be skipped.

Load Order

The files in the initial_data directory are loaded in alphabetical order. If you control the load order, you should make a YAML file called _index.yml, which has a content like this:

- products
- customers
- orders

Options for the InitialTestData.import method

except

The initial-test-data utilizes the database_cleaner gem to truncate all tables except _initial_data_digest and schema_migrations.

If you want to keep some tables intact, specify the except option:

RSpec.configure do |config|
  config.before(:suite) do
    InitialTestData.import('spec', except: %w(country_names))
  end
end

only

Contrary to the except option, when you use this, only the specified tables are initialized:

RSpec.configure do |config|
  config.before(:suite) do
    InitialTestData.import('spec', only: %w(customers products))
  end
end

Note that the except and only options are used to construct the options passed to the DatabaseCleaner.strategy= method.

monitoring

By default the initial-test-data monitors the initial_data directory under the test directory (or the directory specified by the first argument) and the app/models directory.

If you want to add monitoring target directories, specify monitoring option to the InitialTestData.import method:

RSpec.configure do |config|
  config.before(:suite) do
    InitialTestData.import('spec',
      monitoring: [ 'app/services', 'lib', 'spec/factories' ]
  end
end

You should use relative paths from the Rails.root.

quiet

Specify true to this option in order to suppress the info messages from the initial-test-data.

Utility methods: store and fetch

The initial-test-data provides two utility methods, store and fetch, to make it easy to refer the initialized records in your tests.

You can use the store method within the initialization scripts in order to register an ActiveRecord object by name:

include InitialTestData::Utilities

# Using Active Record
store(Customer.create(...), :john)
store(ShopOwner.create(...), :mike)

# Using Factory Girl
store(create(:customer, ...), :john)
store(create(:shop_owner, ...), :john)

Then, you can get this record with fetch method in the test scripts:

customer = fetch(:customer, :john)
shop_owner = fetch(:shop_owner, :mike)

The fetch method treats :john and "john" as the same key.

Note that the initial-test-data creates a YAML file named initial_data_record_ids.yml in the tmp directory to track the primary key values of registered records. Please do not remove or tamper it.

Environment variable REINIT

If you want to enforce the initialization process, add REINIT=1 before the command:

REINIT=1 bin/rake test

When you want to skip it, place REINIT=0 before the command:

REINIT=0 bin/rake test

Example

MiniTest and Active Record

# test/initial_data/customers.rb

include InitialTestData::Utilities

0.upto(9) do |n|
  c = Customer.create(
    email: "test#{n}@example.com",
    given_name: 'John',
    family_name: 'Doe'
  )
  store(c, "test#{n}")
end

# test/integration/manage_customers_test.rb

require 'test_helper'

class ManageCustomersTest < ActionDispatch::IntegrationTest
  test "Change the name of a customer" do
    customer = fetch(:customer, :test0)

    get "/customers/#{customer.id}/edit"
    assert_response :success

    patch "/customers/#{customer.id}",
      customer: { given_name: 'Mike', family_name: 'Smith' }
    assert_redirected_to [ assigns(:customer) ]

    follow_redirect!
    assert_select "h1", "Listing Customers"

    customer.reload

    assert_equal 'Mike', customer.given_name
    assert_equal 'Smith', customer.family_name
  end
end

RSpec, Capybara and Factory Girl

# Gemfile

...
group :test do
  gem 'rspec-rails'
  gem 'factory_girl_rails'
  gem 'initial-test-data'
end
...

# spec/rails_helper.rb

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

FactoryGirl.reload
...

# spec/factories/customers.rb

FactoryGirl.define do
  factory(:customer) do
    sequence(:email) { |n| "test#{n}@example.com" }
    given_name 'John',
    family_name 'Doe'
  end
end

# spec/initial_data/customers.rb

include FactoryGirl::Syntax::Methods
include InitialTestData::Utilities

0.upto(9) do |n|
  c = create(:customer, email: "test#{n}@example.com")
  store(c, "test#{n}")
end

# spec/features/manage_customers_spec.rb

require 'rails_helper'

feature 'Manage customers' do
  let(:customer) { fetch(:customer, :test0) }

  scenario 'Change the name of a customer' do
    visit root_path

    find('table.customers td', text: customer.email)
      .find(:xpath, '..').click_link('Edit')

    fill_in 'Given Name', with: 'John'
    fill_in 'Family Name', with: 'Doe'
    click_button 'Update'

    customer.reload
    expect(customer.given_name).to eq('John')
    expect(customer.family_name).to eq('Doe')
  end
end

License

The initial-test-data is distributed under the MIT license. (MIT-LICENSE)

Author

Tsutomu Kuroda (t-kuroda@oiax.jp)