fixtures_test.rb

require "test_helper"
require "yaml"

class FixtureTest < ActiveSupport::TestCase
  fixtures :all

  Dir[File.join Rails.root, "test", "fixtures", "**", "*.yml"].each do |file|
    if fixtures = YAML.load(IO.read(file))
      kind = File.basename file, ".yml"

      fixtures.each do |key, _|
        define_method "test_#{kind}_#{key}_fixture" do
          model = send kind, key.to_sym
          valid = model.valid?

          assert model.valid?, "Expected #{kind}(:#{key}) to be valid, but " +
            model.errors.full_messages.to_sentence
        end
      end
    end
  end
end