7/29/2019 RSpec1

1/38

1

RSpec IRSpec I

Sang ShinSang Shinhttp://www.JPassion.comhttp://www.JPassion.com

Learn with JPassion!Learn with JPassion!

1

7/29/2019 RSpec1

2/38

2

RSpec I: Topics

What is and Why RSpec?

Installing and running RSpec

RSpec vocabulary

Subject Model testing with RSpec

RSpec tools Spork, Guard

The following topics will be covered in RSpec II.

Controller testing, View testing, more RSpec tools (Factory Girl,Faker, Capybara, Launchy)

7/29/2019 RSpec1

3/38

What is & Why RSpec?What is & Why RSpec?

7/29/2019 RSpec1

4/38

4

What is RSpec?

Ruby DSL (Domain Specific Language) for specifying thedesired behavior of Ruby code

Testing tool for the Ruby programming language

Born under the banner of BDD (Behaviour-Driven Development) Make TDD(Test-Driven Development) a productive and

enjoyable experience

Used to create unit, functional and integration testing

7/29/2019 RSpec1

5/38

5

Steps for BDD Testing using RSpec

Repeat the following steps

> Step #1: Write behavior of some test target as a set of specexamples

> Step #2: Run the test and experience test failures

> Step #3: Write code (or refactor code) to correct the test failures

7/29/2019 RSpec1

6/38

6

Why RSpec?

RSpec scripts (simply called specs) enables building readabletesting logic

> Descriptions attached to the blocks of code form readablesentences, which describe the desired behavior

> Documentation, testing, code are very much aligned A better and more popular alternative to default Rails test

system

7/29/2019 RSpec1

7/387

Displaying Bahavior/Examples

Display all examples in readable format

7/29/2019 RSpec1

8/388

RSpec Features

a rich command line program (the rspec command)

textual descriptions of examples and groups (rspec-core)

flexible and customizable reporting

extensible expectation language (rspec-expectations) built-in mocking/stubbing framework (rspec-mocks)

7/29/2019 RSpec1

9/38

Installing of &Installing of &Running RSpecRunning RSpec

7/29/2019 RSpec1

10/3810

RSpec Installation

Add rspec-rails gem in Gemfile and perform bundle install

group :development, :test do gem 'rspec-rails', "~> 2.0.1"end

Generate RSpec configuration filesrails generate rspec:install

7/29/2019 RSpec1

11/3811

Running RSpec (using rspec)

Run all specs

rspec spec

Run all model specs

rspec spec/models

Run a particular model spec

rspec spec/models/student_spec.rb

Run a particular model spec with 'documentation format

rspec spec/models/student_spec.rb --format documentation

7/29/2019 RSpec1

12/3812

Running RSpec (using rake)

You can also use rake to run RSpec

C:\rails_projects\rspec_app>rake -T spec

rake spec # Run all specs in spec directory (excluding plugin ...

rake spec:controllers # Run the code examples in spec/controllers

rake spec:helpers # Run the code examples in spec/helpersrake spec:lib # Run the code examples in spec/lib

rake spec:mailers # Run the code examples in spec/mailers

rake spec:models # Run the code examples in spec/models

rake spec:rcov # Run all specs with rcovrake spec:requests # Run the code examples in spec/requests

rake spec:routing # Run the code examples in spec/routing

rake spec:views # Run the code examples in spec/views

7/29/2019 RSpec1

13/3813

Demo:Demo:

Exercise 1: Configure RSpec toExercise 1: Configure RSpec toa Rails Applicationa Rails Application

5541_rails_rspec1.zip5541_rails_rspec1.zip

7/29/2019 RSpec1

14/38

RSpec VocabularyRSpec Vocabulary

7/29/2019 RSpec1

15/3815

Test::Unit vs RSpec

class SomethingTest

def test_talk

assert_xxx

def setup def teardown

describe Something

it should talk

object.should be_xxx

before(:each) { }, before(:all) {} after(:each) { }, after(:all) { }

pending

let

expect

context

specify

7/29/2019 RSpec1

16/3816

RSpec Verification Methods

RSpec provides two verification methods that are available for allobjects

> should> should_not

Examples> aObject.should respond_to(:attribute)> aObject.should be_valid> aObject.should be_nil> aObject.done?.should be_true> {:a => 'b'}.should have_key(:a), {:a => 'b'}.should_not have_key(:x)> 'a string'.should be_an_instance_of(String)> result.should equal(5)> message.should match(/hello/), message.should =~ /hello/

7/29/2019 RSpec1

17/3817

Spec Example

describe defines a behavior, which is a collection of examples

it defines an example

require 'spec_helper'

describe Student dobefore { @student = Student.new }

it "should have name field" do

@student.should respond_to(:name)endit "should have age field" do

@student.should respond_to(:age)end

end

7/29/2019 RSpec1

18/3818

Pending tests

Used to add testing examples without testing logic

describe Student doit "should have age field" do

pending to be implemented laterend

# If it method does not have do..end code block, it is# considered as a pending testit "should have name field"

end

7/29/2019 RSpec1

19/3819

describe & context

describe method is used to group together related(specification) examples of behavior

> describe method returns Behaviorobject

describe method takes two arguments

> String description (or Model for Model spec)> do... end code block that contains a set of it methods

Can be nested

> The code block of outer describe can contain sets of innerdescribe's

context is an alias for describe

> Use describe for things and use context for context

7/29/2019 RSpec1

20/38

20

it

it defines (specification) example

it method takes description and a do.. end code block (similarto describe method)

Verification always occur within the context of it block

Limit one expectation to one it block

7/29/2019 RSpec1

21/38

21

before & after

beforeand after methods executes code before and after> :each - executes code before each test> :all executes code once for all tests

describe Student dobefore(:each) { @student = Student.new }

it "should have name field" do@student.should respond_to(:name)

endit "should have age field" do

@student.should respond_to(:age)endit "should have email field" do

@student.should respond_to(:email)end

end

7/29/2019 RSpec1

22/38

22

let

let method executes code once and stored it for furtherinvocation, increasing the performance

describe Student do#before { @student = Student.new }

let (:student) { Student.new }

it "should have name field" do#@student.should respond_to(:name)

student.should respond_to(:name)end

it "should have age field" do#@student.should respond_to(:age) student.should respond_to(:age)

endit "should have email field" do

#@student.should respond_to(:email) student.should respond_to(:email)

endend

7/29/2019 RSpec1

23/38

23

expect

Used when a method is expected to change a value or throw anan exception

describe Student do

it "should increase the number of instances by 1 when new instancegets created" do expect {

Student.create}.to change {Student.count}.by(1)# }.to change {Student.count}.to(1)

# }.to change {Student.count}.from(0).to(1)end

end

7/29/2019 RSpec1

24/38

SubjectSubject

7/29/2019 RSpec1

25/38

25

What is a Subject?

Every RSpec example group represented by describe - hasa subject

A subject represents the thing that is being described

Could be implicit subject or explicit subject

7/29/2019 RSpec1

26/38

26

Implicit Subject

An implicit subject gets created automatically when the firstargument to the "describe" is a Model class

The implicit object can be referenced as "subject".

require 'spec_helper'

describe Student do

it "should have name field" do subject.should respond_to(:name)endit "should have age field" do

subject.should respond_to(:age)

endend

7/29/2019 RSpec1

27/38

27

Explicit Subject

You can create an subject explicitly for example, when youneed to create a subject with non-default property values

require 'spec_helper'

describe Student dobefore { @student = Student.new(:name =>Shin) }

it "should have name field" do

@student.should respond_to(:name)endit "should have age field" do

@student.should respond_to(:age)end

end

7/29/2019 RSpec1

28/38

28

Demo:Demo:

Exercise 2: Learn RSpec vocabularyExercise 2: Learn RSpec vocabulary5541_rails_rspec1.zip5541_rails_rspec1.zip

7/29/2019 RSpec1

29/38

Model TestingModel Testing

with RSpecwith RSpec

7/29/2019 RSpec1

30/38

30

Models: What to test

Attribute presence

Validation

Associations

Instance or class methods Custom finders

Callbacks

Scopes

7/29/2019 RSpec1

31/38

31

Attribute Presence Test

Studenthas name and age attributes

require 'spec_helper'

describe Student dobefore (:each) { @student = Student.new }

it "should have name field" do@student.shouldrespond_to(:name)

endit "should have age field" do

@student.shouldrespond_to(:age)end

end

7/29/2019 RSpec1

32/38

32

Validation Test

Example validation tests

describe Student doit 'is not valid when name is null' do

@student = Student.new

@student.should_not be_validendit 'is not valid when the length of name is less than 3' do

@student = Student.new(:name => 'ab')@student.should_not be_valid

endit 'is not valid when age is not numerical value' do

@student = Student.new(:name =>'Sang', :age => 'abc')@student.should_not be_valid

endit 'is not valid when age is between 5 and 95' do

@student = Student.new(:name =>'Sang', :age => 3)@student.should_not be_valid

endend

7/29/2019 RSpec1

33/38

33

Association Test

Are association methods present?

Does the association refers to a correct object?describe Book do

it "belongs to a student" do@book = Book.new@book.should respond_to(:student)

end

it "should have the right associated student" do@student = Student.create(:name => "Student1", :age => 30)@book = @student.books.create(:title => "JPassion", :author => "Sang Shin")

@book.student_id.should == @student.id@book.student.should == @studentend

end

7/29/2019 RSpec1

34/38

34

Demo:Demo:

Exercise 3: Perform Model Spec TestingExercise 3: Perform Model Spec Testing5541_rails_rspec1.zip5541_rails_rspec1.zip

7/29/2019 RSpec1

35/38

RSpec ToolsRSpec Tools

7/29/2019 RSpec1

36/38

36

RSpec Tools

Spork> Everytime RSpec testing is performed, a new Rails environment

needs to be created, which takes time> Spork loads Rails environment just once and all subsequent

RSpec uses it, thus saving time for Rails environment creation Guard

> Guard launch specs automatically & intelligently when files aremodified.

7/29/2019 RSpec1

37/38

37

Demo:Demo:

Exercise 4: Use SporkExercise 4: Use SporkExercise 5: Use GuardExercise 5: Use Guard

5541_rails_rspec1.zip5541_rails_rspec1.zip

7/29/2019 RSpec1

38/38

Thank you!Thank you!

Check JavaPassion.com Codecamps!Check JavaPassion.com Codecamps!http://www.javapassion.com/codecampshttp://www.javapassion.com/codecamps

http://www.javapassion.com/codecampshttp://www.javapassion.com/codecampshttp://www.javapassion.com/codecamps