MiniTest and VCR: one cassette per test?

test_with_cassette.rb

module TestWithCassette
  # cribbed from Rails and modified for VCR
  # https://github.com/rails/rails/blob/b451de0d6de4df6bc66b274cec73b919f823d5ae/activesupport/lib/active_support/testing/declarative.rb#L9
  def test_with_cassette(name, vcr_options = {}, &block)
    auto_cassette_name = name.gsub(/\s+/, '_')
    test_name = "test_#{auto_cassette_name}".to_sym

    if block_given?
      group = vcr_options.delete(:group)
      group_prefix =  "#{group}/" if group.present?
      cassette = vcr_options.fetch(:cassette, auto_cassette_name)
      vcr_options = { tag: group }.merge(vcr_options) if group

      define_method(test_name) do
        VCR.use_cassette("#{group_prefix}#{cassette}", vcr_options) do
          instance_eval &block
        end
      end
    else
      define_method(test_name) do
        flunk "No implementation provided for #{name}"
      end
    end
  end
end

very_example_test.rb

class VeryExampleTest < ActiveSupport::TestCase
  extend TestWithCassette

  # automatic cassette 'do_something', in 
  # test method test_do_something. 
  test_with_cassette 'do something' do
    # …
  end

  # optional group name will add a :tag with that group name to use_cassette,
  # as well as put the cassette in a subdir named after group
  test_with_cassette 'something else', group: :examples do
    # …
  end

  # override tag, override cassette name, supply other VCR options
  test_with_cassette 'much options', group: :examples, cassette: 'custom_name', tag: :whatever, vcr_options: :supported do
    # …
  end
end