Fiber sample

fiber_spec.rb

# coding: utf-8

require 'rspec'
require 'fiber'

describe 'FiberTest' do
  let(:fiber) do
    Fiber.new do |name|
      last_name = Fiber.yield("#{name}")
      "#{name} #{last_name}"
    end
  end

  describe '.current()' do
    subject { Fiber.current() }
    it { should be_instance_of(Fiber) }
  end

  # Can't yield from root fiber
  describe '.yield()' do
    subject { Fiber.yield("pochi") }
    it do
      expect { subject }.to raise_exception(FiberError)
    end
  end

  describe '#alive?' do
    describe 'when fiber alive' do
      context 'never called' do
        subject { fiber.alive? }
        it { should be_true }
      end

      context 'once called' do
        before { fiber.resume("pochi") }
        subject { fiber.alive? }
        it { should be_true }
      end
    end

    context 'when fiver dead' do
      before { 2.times { |_| fiber.resume("pochi") } }
      subject { fiber.alive? }
      it { should be_false }
    end
  end

  describe '#resume(name)' do
    context 'when once called' do
      subject { fiber.resume("pochi") }
      it { should == "pochi" }
    end

    context "when twice called" do
      before { fiber.resume("pochi") }
      subject { fiber.resume("kuroda") }
      it do
        pending 'Test should not work'
        should = "kuroda pochi"
      end
    end
  end
end

describe 'FiberSample' do
  before do
    @num = 1
    @fiber = Fiber.new do
      loop { Fiber.yield @num; @num+=1 }
    end
  end

  context 'calc' do
    subject { 10.times { |_| @fiber.resume } }
    it { should == 10 }
  end

  context 'calc2' do
    before do
      @twice_fiber = Fiber.new do
        loop { Fiber.yield @num; @num+=2}
      end

      10.times do |_|
        @fiber.resume
        @twice_fiber.resume
      end
    end

    subject do
      @twice_fiber.resume
    end

    it { should == 30 }
  end
end