VCR cassettes relative to the current describe/context block

my_class_spec.rb

require 'spec_helper'

module Module1
  describe Module2::MyClass do
    let(:my_instance) { Module1::Module2::MyClass.new('abc', 123) }

    context 'super cool context' do
      # Use cassette Module1_Module2_MyClass/super_cool_context/neat_method.yml
      describe 'neat_method', vcr: relative_cassette('neat_method') do
        subject { my_instance.neat_method(id) }

        it 'does something' do
          # ...
        end

        it 'does something else' do
          # ...
        end
      end
    end
  end
end

vcr_cassette_helpers.rb

# spec/support/vcr_cassette_helpers.rb

# Returns VCR options specifying the path to the given cassette, found in a
# directory for the current context/describe block.
def relative_cassette cassette_name
  context = get_rspec_context(metadata)
  # 'Module1_Module2_MyClass/super_cool_context'
  path_to_cassette = context.map {|name| name.gsub(/::/, '_').gsub(/\s/, '_') }.
                             join('/')
  {cassette_name: path_to_cassette + '/' + cassette_name}
end

# e.g., ["Module1::Module2::MyClass", "super cool context"]
def get_rspec_context metadata, context=[]
  if metadata.has_key?(:example_group)
    get_rspec_context metadata[:example_group], context
  end
  context << metadata[:description_args]
  context.reject(&:blank?).map {|args| args.first.to_s }
end