rspec cheat sheet

rspec_cheat_sheet.rd

INSTALL
=======

$ gem install rspec

RSPEC-RAILS
===========

  RAILS-3
  =======

    CONFIGURE THE GEMFILE
    ======================
    group :development, :test do
      gem "rspec-rails", "~> 2.0"
    end

    INSTALL THE BUNDLE
    ===============================
    $ bundle install

    BOOTSTRAP THE APP
    ================= 
    $ ./script/rails generate rspec:install
          create  .rspec
          create  spec
          create  spec/spec_helper.rb
          create  autotest
          create  autotest/discover.rb

  RAILS-2
  =======

    INSTALL
    =======
    $ gem install rspec-rails -v 1.3.3

    BOOTSTRAP THE APP
    =================
    $ ./script/generate rspec
        create  spec
        create  spec/spec_helper.rb
        create  spec/spec.opts
        create  previous_failures.txt
        create  script/spec_server
        create  script/spec

HOW TO USE
==========

  COMMAND LINE
  =============
rspec --color --format doc spec/widget_spec.rb

  RAILS 3 (RSPEC 2)
  =============
./rails/generate model User
rake -T spec # lists all rspec rake tasks
rake spec # run all specs
rake spec/models/mymodel_spec.rb # run a single spec file
rake spec/models/mymodel_spec.rb:27 # run a single example or group on line 27

  RAILS 2 (RSPEC 1)
  =============
./script/generate rspec_model User
rake -T spec # lists all rspec rake tasks
rake spec # run all specs
rake spec SPEC=spec/models/mymodel_spec.rb SPEC_OPTS="-e \"should do
something\"" #run a single spec



module UserSpecHelper
  def valid_user_attributes
    { :email => "[email protected]",
      :username => "joebloggs",
      :password => "abcdefg"}
  end
end


describe "A User (in general)" do
  include UserSpecHelper

  before(:each) do
    @user = User.new
  end

  it "should be invalid without a username" do
    pending "some other thing we depend on"
    @user.attributes = valid_user_attributes.except(:username)
    @user.should_not be_valid
    @user.should have(1).error_on(:username)
    @user.errors.on(:username).should == "is required"
    @user.username = "someusername"
    @user.should be_valid
  end
end

EXPECTATIONS
=====================
target.should satisfy {|arg| ...}
target.should_not satisfy {|arg| ...}

target.should equal <value>
target.should not_equal <value>

target.should be_close <value>, <tolerance>
target.should_not be_close <value>, <tolerance>

target.should be <value>
target.should_not be <value>

target.should predicate [optional args]
target.should be_predicate [optional args]
target.should_not predicate [optional args]
target.should_not be_predicate [optional args]

target.should be < 6
target.should == 5
target.should be_between(1, 10)
target.should_not == 'Samantha'

target.should match <regex>
target.should_not match <regex>

target.should be_an_instance_of <class>
target.should_not be_an_instance_of <class>

target.should be_a_kind_of <class>
target.should_not be_a_kind_of <class>

target.should respond_to <symbol>
target.should_not respond_to <symbol>

lambda {a_call}.should raise_error
lambda {a_call}.should raise_error(<exception> [, message])
lambda {a_call}.should_not raise_error
lambda {a_call}.should_not raise_error(<exception> [, message])

proc.should throw <symbol>
proc.should_not throw <symbol>

target.should include <object>
target.should_not include <object>

target.should have(<number>).things
target.should have_at_least(<number>).things
target.should have_at_most(<number>).things

target.should have(<number>).errors_on(:field)

expect { thing.approve! }.to change(thing, :status).
    from(Status::AWAITING_APPROVAL).
    to(Status::APPROVED)

expect { thing.destroy }.to change(Thing, :count).by(-1)

Mocks and Stubs
===============
user_mock = mock "User"
user_mock.should_receive(:authenticate).with("password").and_return(true)
user_mock.should_receive(:coffee).exactly(3).times.and_return(:americano)
user_mock.should_receive(:coffee).exactly(5).times.and_raise(NotEnoughCoffeeExcep
ion)

people_stub = mock "people"
people_stub.stub!(:each).and_yield(mock_user)
people_stub.stub!(:bad_method).and_raise(RuntimeError)

user_stub = mock_model("User", :id => 23, :username => "pat", :email =>
"[email protected]")

Examples (in the real world)
============================
http://madhatted.com/2008/7/10/rspec-real-world-testing
presentation: http://kerryb.github.com/iprug-rspec-presentation/#31