Peck

Peck is a concurrent spec framework.

Getting Started

You can install Peck as a gem.

$ gem install peck

Write a little test.

require 'peck/flavors/vanilla'

describe MicroMachine do
  it "drives really fast" do
    MicroMachine.should.drives(:fast)
  end
end

And enjoy the output.

ruby -rubygems spec/micro_machine_spec.rb -e ''
.
1 spec, 0 failures, finished in 0.0 seconds.

Why another framework/test library/spec language?

I guess that's something you will have to find out for yourself. For us a spec framework needs two things: a good way to describe intention of the specs and flexibility to work with the different types of project we work on.

We really like Bacon and test/spec but we've found that they're to limiting in some of our projects. Bacon doesn't work really well with Rails and test/spec needs test/unit, which will be gone in Ruby 1.9.

In some projects we find that we have an enormous amount of little specs which beg to be run concurrently.

Peck tries to be what we, and maybe you, need it to be. Within reason of course.

Peck can be concurrent

Peck has two run modes: serial and concurrent. Right now that's a global setting for the whole suite.

Peck.concurrency = 9

Some projects don't allow concurrency because either the code or the test suite aren't thread safe. We've also found that some suites actually run slower in threads.

Peck can host your own spec syntax

When implementing your own spec syntax you only have to add expectations to a little accessor when they run and raise Peck::Error when something fails.

describe "Fish" do
  it "breathes with water" do
    # If you don't like .should, you can write your own assertion
    # DSL
    expects {
      Fish.breathes == water
    }
  end
end

With a bit of work you could make Peck run your Rspec tests.

Peck has a pluggable notification system

You can write your own notifiers and register them with Peck's delegate system.

class Remotifier < Peck::Notifiers::Base
  def finished
    HTTP.post("https://ci.lan/runs?ran=#{Peck.counter.ran}" +
      "&failures=#{Peck.counter.failed}")
  end
end
Remotifier.use

Peck is extensible

Except opening up Peck classes you can also extend during runtime with the once callback. This callback is ran when a new context (describe) is created.

Peck::Context.once do |context|
  context.class_eval do
    attr_accessor :controller_class

    before do
      @controller = controller_class.new
    end
  emd
end

Except extension you can also add should macros which defined one or more specifications:

class Peck::Should::Specification
  class Disallow < Peck::Should::Proxy
    def get(action)
      context.it("disallows GET on `#{action}'") do
        get action
        response.should == :unauthorized
      end
    end
  end

  def disallow
    Peck::Should::Specification::Disallow.new(context)
  end
end

describe CertificatesController, "when accessed by a regular user" do
  before do
    login :regular_user
  end

  should.disallow.get :index
  should.disallow.get :show
end

Flavors

You can either require parts of Peck you're using for your test suite or require an entire flavor. Flavors are pre-built configurations for common use cases. Right now there are three flavors:

Vanilla

require 'peck/flavors/vanilla'

Reports running specs with dots and ends with a short report.

Quiet

require 'peck/flavors/quiet'

Runs your specs but doesn't report the results. This is useful when testing Peck itself or your extensions for Peck.

If you want to learn more about testing Peck itself read examples/preamble.rb.

In the quiet flavor we do keep a counter, so you could write your own formatter using Peck.counter.

Documentation

The documentation runner is based on various other ‘documentation’ runners which are generally used for running on CI. This flavor reports the entire label for a spec and colored output. It also shows the runtime for a spec and can report slow specs.

You can configure the report cutoff for slow specs. By default it's configured at 500ms.

require 'peck/notifiers/documentation'
Peck::Notifiers::Documentation.runtime_report_cutoff = 20 # milliseconds

Assertions

Peck is still very much in flux and will probably change a lot in the coming months. Currently we support a small number of assertions:

• should, should.not, and should.be
• should.equal
• should.raise([exception]) { }
• should.change([expression]) { }
• should.satisfy { |object| }

Change

You can check for changes in an expression.

lambda do
  Person.create
end.should.change('Person.count')

Or check for specific changes.

lambda do
  Person.create
  Person.create
end.should.change('Person.count', +2)

Or check for multiple changes.

lambda do
  Library.bootstrap
end.should.change(
  'Shelf.count', +12,
  'Book.count', +243
)

If you want to learn more you're probably best of reading the code documentation.

Copying

Peck inherits a lot of ideas, concepts and even some implementation from both Bacon and MacBacon. Both of these projects have been released under the terms of an MIT-style license.

Copyright (C) 2007 - 2012 Christian Neukirchen http://purl.org/net/chneukirchen Copyright (C) 2011 - 2012 Eloy Durán eloy.de.enige@gmail.com Copyright (C) 2012 Manfred Stienstra, Fingertips manfred@fngtps.com

Peck is freely distributable under the terms of an MIT-style license. See COPYING or http://www.opensource.org/licenses/mit-license.php.