Rspec cheatsheet

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])
  lambda {a_call}.should change(instance, method).from(number).to(number)
  
  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]")
  
  my_instance.stub!(:msg).and_return(value)
  MyClass.stub!(:msg).and_return(value)
  
  Examples (in the real world)

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

--

Cheers! Manish shrivastava