HasSecureToken extension for shoulda-matchers gem while using has_secure_token gem

application.rb

# config/application.rb
module YourApp
  class Application < Rails::Application

    # ...

    # Auto load lib folder
    config.autoload_paths << Rails.root.join('lib')
  end
end

have_secure_token.rb

# lib/shoulda/matchers/active_model/have_secure_token.rb
module Shoulda
  module Matchers
    module ActiveModel

      def have_secure_token(attr)
        HaveSecureTokenMatcher.new(attr)
      end

      # @private
      class HaveSecureTokenMatcher
        attr_reader :failure_message

        EXPECTED_METHODS = [
          :regenerate_token,
        ]

        MESSAGES = {
          method_not_found: "expected %{subject} to respond to %{methods}",
          did_not_persist_record: "expected %{subject} to be persisted to the database",
          did_not_save_with_secure_token: "expected %{subject} to save and with a secure %{attribute}",
        }

        def initialize(attribute)
          @attribute = attribute.to_sym
        end

        def description
          "have a secure #{attribute}"
        end

        def matches?(subject)
          @subject = subject

          if failure = validate
            key, params = failure
            @failure_message = MESSAGES[key] % { subject: subject.class }.merge(params)
          end

          failure.nil?
        end

        protected

        attr_reader :subject, :attribute

        def validate
          EXPECTED_METHODS << attribute
          missing_methods = EXPECTED_METHODS.select {|m| !subject.respond_to?(m) }

          if missing_methods.present?
            [:method_not_found, { methods: missing_methods.to_sentence }]
          else
            subject.send("#{attribute}=", nil)
            subject.regenerate_token

            if subject.changed?
              [:did_not_persist_record, {}]
            end

            if subject.send(attribute).nil?
              [:did_not_save_with_secure_token, { attribute: attribute }]
            end
          end
        end
      end
    end
  end
end

shoulda-matchers.rb

# config/initializers/shoulda-matchers.rb
require 'shoulda/matchers/active_model/have_secure_token_matcher'