require 'benchmark'

module BenchmarkHelpers
  def benchmark(description, &block)
    # 1. Nope
    #bm_proc = Proc.new do
    #  db = Proc.new { |bm| bm.report(description, &block) }
    #  Benchmark.bm(description.length, &db)
    #end
    it description do
      Benchmark.bm(description.length) do |bm|
        # 2. Nada
        #bm.report description, &block
        bm.report description do
          # 3. Zilch
          block.yield
        end
      end
    end
  end
end

RSpec.configure do |c|
  c.extend BenchmarkHelpers
end

describe "scopes" do
  it "succeeds" do
    true.should == true # success
    true.should be      # success
  end
  benchmark "throws exception on 'be'" do
    true.should == true # success
    true.should be      # exception
  end
end


rake spec SPEC=spec/benchmark_spec.rb
/home/aaron/.rvm/rubies/ruby-1.9.2-p290/bin/ruby -S bundle exec rspec spec/benchmark_spec.rb

scopes
                      user     system      total        real
how do they work  how do they work (FAILED - 1)

Failures:

  1) scopes how do they work
     Failure/Error: true.should be
     NameError:
       undefined local variable or method `be' for RSpec::Core::ExampleGroup::Nested_1:Class
     # ./spec/benchmark_spec.rb:25:in `block (2 levels) in <top (required)>'
     # ./spec/benchmark_spec.rb:12:in `yield'
     # ./spec/benchmark_spec.rb:12:in `block (3 levels) in benchmark'
     # /home/aaron/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/benchmark.rb:295:in `measure'
     # /home/aaron/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/benchmark.rb:382:in `item'
     # ./spec/benchmark_spec.rb:11:in `block (2 levels) in benchmark'
     # /home/aaron/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/benchmark.rb:178:in `benchmark'
     # /home/aaron/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/benchmark.rb:208:in `bm'
     # ./spec/benchmark_spec.rb:10:in `block in benchmark'