valid_attribute

ValidAttribute

ValidAttribute is a minimalist matcher for validation BDD.

Supported ORMs

• ActiveModel based (ActiveRecord >= 3.0, Mongoid >= 2.0, MongoMapper >= 0.9)
• ActiveRecord <= 2.3
• DataMapper
• Custom (with compatible API, see below)

Installation

If you're using RSpec just add the valid_attribute to your Gemfile AFTER rspec gem.

gem 'valid_attribute'

Then add it to your spec_helper.rb

require 'valid_attribute'

or if you're using Test::Unit, you must use Thoughtbot's shoulda-context

# Gemfile
gem 'shoulda-context'

# test_helper.rb
require 'shoulda-context'
require 'valid_attribute'

If you want to you use it with MiniTest::Spec you can use either shoulda-context (see above) or minitest-matchers:

# Gemfile
gem 'minitest-matchers'

# test_helper.rb
require 'valid_attribute'

Usage

Instead of having validation specific matchers ValidAttribute only cares if the attribute is valid under certain circumstances

class User
  include ActiveModel::Validations

  attr_accessor :email, :name, :password

  validates :email,    :format => { :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i }
  validates :name,     :length => { :minimum => 5 }
  validates :password, :confirmation => true, :presence => true
end

# RSpec
describe User do
  # The .when method can take any number of values that you want to pass
  it { should have_valid(:email).when('[e-mail]', '[e-mail]') }
  it { should_not have_valid(:email).when('fail', 123) }
  it { should have_valid(:name).when('TestName') }
  it { should_not have_valid(:name).when('Test') }

  # Because 'should' works off the the 'subject' in RSpec we can set other values if necessary for a given validation test
  describe 'password' do
    before { subject.password_confirmation = 'password' }
    it { should have_valid(:password).when('password') }
    it { should_not have_valid(:password).when(nil) }
  end

  # Using .when is optional. Without it, the existing value is examined.
  it { should_not have_valid(:email) }
end

# TestUnit
require 'shoulda/context'
class UserTest < Test::Unit::TestCase
  # The .when method can take any number of values that you want to pass
  should have_valid(:email).when('[e-mail]', '[e-mail]')
  should_not have_valid(:email).when('fail', 123)
  should have_valid(:name).when('TestName')
  should_not have_valid(:name).when('Test')

  # Because 'shoulda-context' works off the 'subject' we can set other values if necessary for a given validation test
  context 'password' do
    subject { User.new(:password_confirmation => 'password') }
    should have_valid(:password).when('password')
    should_not have_valid(:password).when(nil)
  end

  # Using .when is optional. Without it, the existing value is examined.
  should_not have_valid(:email)
end

# Minitest::Matchers
require 'minitest/matchers'
describe User do
  subject { User.new }

  it { must have_valid(:email).when('[e-mail]', '[e-mail]') }
  it { wont have_valid(:email).when('fail', 123) }
  it { must have_valid(:name).when('TestName') }
  it { wont have_valid(:name).when('Test') }

  describe 'password' do
    subject { User.new.tap { |u| u.password_confirmation = "password" } }
    it { must have_valid(:password).when('password') }
    it { wont have_valid(:password).when(nil) }
  end
end

Custom Models

Your model should respond to the following methods:

• valid? - only used to generate errors on the model
• errors - should be a Hash of attributes that have the invalid attributes as keys.

The following would be a compatible (albeit unrealistic) model:

class User
  attr_accessor :name

  def errors
    {:name => ["can't be blank"]}
  end

  def valid?
    false
  end
end

Don't Repeat Yourself

# encoding: utf-8

# RSpec
describe User do
  let(:names) { ['TestName', 'Test-name', "O'Namey", 'Maček'] }
  it { should have_valid(:first_name).when *names }
  it { should have_valid(:last_name).when *names }
end

Cloning

If you feel that the setters are mutating parts of the object when testing multiple values you can force the test subject be cloned in between each test

it { should have_valid(:name).when('Brian').clone }

Be aware the cloning can cause some unpredicatable results and may lead to more pain than help

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Licensed under the MIT license