shoulda-matchers.md

Shoulda matchers Provide one liner solutions for testing common functinoalities (like rails validations, AR relations and controller behaviors)

Example

Without matchers

it 'validates presence of name attribute' do
  subject.name = nil
  
  is_expected.to_not be_valid
  expect(user.errors.full_messages).to include "Name can't be blank"
end

Using matchers

it { is_expected.to validate_presence_of(:name) }

Real example - Amazon account model

it do
  is_expected.to validate_presence_of(:upload_limit)
  is_expected.to validate_numericality_of(:upload_limit).is_greater_than_or_equal_to(0)
  is_expected.to validate_presence_of(:delist_limit)
  is_expected.to validate_numericality_of(:delist_limit).is_greater_than_or_equal_to(0)
  is_expected.to validate_presence_of(:region)
  is_expected.to validate_inclusion_of(:region).in_array(described_class::REGIONS)
end