free_mutant/spec/unit/mutant/isolation_spec.rb

RSpec.describe Mutant::Isolation::None do
  before do
    @initial = 1
  end

  describe '.run' do
    let(:object) { described_class }

    it 'does not isolate side effects' do
      object.call { @initial = 2 }
      expect(@initial).to be(2)
    end

    it 'return block value' do
      expect(object.call { :foo }).to be(:foo)
    end

    it 'wraps *all* exceptions' do
      expect { object.call { fail  } }.to raise_error(Mutant::Isolation::Error)
    end

  end
end

RSpec.describe Mutant::Isolation::Fork do
  before do
    @initial = 1
  end

  describe '.run' do
    let(:object) { described_class }

    it 'does isolate side effects' do
      object.call { @initial = 2  }
      expect(@initial).to be(1)
    end

    it 'return block value' do
      expect(object.call { :foo }).to be(:foo)
    end

    it 'wraps Parallel::DeadWorker exceptions' do
      expect { object.call { fail Parallel::DeadWorker } }.to raise_error(Mutant::Isolation::Error)
    end

    it 'wraps Parallel::DeadWorker exceptions caused by crashing ruby' do
      expect do
        object.call do
          # Silence rb_bug writes
          $stderr.reopen(File.open('/dev/null', 'w'))
          fail RbBug.call
        end
      end.to raise_error(Mutant::Isolation::Error)
    end

  end
end