The document discusses Test Driven Development (TDD) in Ruby on Rails, outlining its importance and procedures for implementing it by writing tests before coding. It provides an overview of the typical directory structure for a Rails application and includes examples of unit tests, highlighting the validation of user attributes. Additionally, it covers the creation and preparation of test databases and various testing scenarios to validate functionality and ensure correct application behavior.

1. Test Driven Development By Uma Mahesh Varma

2. Test Drive Development Introduction Importance of T.T.D Rails webs application directory structure Explanation about test folder in rails directory structure Unit Tests Functional Tests

3. What is meant by test drive development ? The answer for the above question is as fallows, TTD (Test Drive Development) is an part of software development techniques based on writing some small test cases before implementing code or new functionalities. Test drive development is nothing but developing a product by writing unit tests that define the code requirement. These tests returns true or false. Running these tests rapidly brings you a correct behavior of the developer to develop an application.

4. Procedure of T.D.D Write a test. Run the test and check whether it fails or not. If not Write some code. Run the automated test. Refactor.

5. Rails webs application directory structure my_app/ README Installation and usage information Rakefile Build script app/ Model, View, and Controller files go here components/ Reusable components config/ Configuration and database connection parameters db/ Schema and migration information doc/ Autogenerated documentation lib/ Shared code log/ Logfiles produced by your application public/ Web-accessible directory. Your application runs from here script/ Utility scripts test/ Unit, functional, and integration tests, fixtures, and mocks tmp/ Runtime temporary files vendor/ Imported code

6. Test directory Fixtures Integration Functional Unit test_helper.rb

7. Unit Test require File.dirname(__FILE__) + '/../test_helper‘ class UserTest < Test::Unit::TestCase fixtures :users def test_truth assert true end end

8. Unit Test >> ruby test/unit/test_user.rb Loaded suite test/unit/user_test Started EE Finished in 0.559942 seconds. 1) Error: test_truth(UserTest): MysqlError: Unknown database ‘myapp_test' 1 tests, 0 assertions, 0 failures, 2 errors

9. Unit Test A Database Just for Tests Myapp> mysqladmin -u root create myapp_test Myapp> ruby test/unit/myapp_test.rb Loaded suite test/unit/myapp_test Started E Finished in 0.06429 seconds. 1) Error: test_truth(ProductTest): ActiveRecord::StatementInvalid: MysqlError: Table ‘myapp_test. users' doesn't exist: DELETE FROM users 1 tests, 0 assertions, 0 failures, 1 errors

10. Unit Test myapp > rake db:test:prepare Myapp > ruby test/unit/user_test.rb Loaded suite test/unit/user_test Started . Finished in 0.085795 seconds. 1 tests, 1 assertions, 0 failures, 0 errors

11. Unit Test A Real Unit Test validates_presence_of :name, :email, :mobilenum validates_numericality_of : mobilenum validates_uniqueness_of :name validates_format_of :image_url, :with => %r{\.(gif|jpg|png)$}i, :message => &quot;must be a URL for a GIF, JPG, or PNG image&quot;

12. Unit Test def test_invalid_with_empty_attributes user = User.new assert ! user .valid? assert user .errors.invalid?(:name) assert user .errors.invalid?(:email) assert user .errors.invalid?(:mobileno) assert user.errors.invalid?(:image_url) end

13. Unit Test Myapp > ruby test/unit/user_test.rb Loaded suite test/unit/user_test Started .. Finished in 0.092314 seconds. 2 tests, 6 assertions, 0 failures, 0 errors

14. Unit Test def test_image_url ok = %w{ fred.gif fred.jpg fred.png FRED.JPG FRED.Jpg http://a.b.c/x/y/z/fred.gif } bad = %w{ fred.doc fred.gif/more fred.gif.more } ok.each do |name| user = User.new(:name => “mahesh&quot; , :email => “umamahesh_nyros@yahoo.com&quot; , :mobilenum => 9866439593, :image_url => name) assert user.valid?, usererrors.full_messages end bad.each do |name| user = User.new(:name => “mahesh&quot; , :email => “umamahesh_nyros@yahoo.com&quot; , :mobilenum => 9866439593, :image_url => name) assert user.valid?, usererrors.full_messages end

15. Fixtures mahesh: id: 1 name: mahesh email: [email_address] mobilenum: 9866439593 image_url: maheshprofile.jpg

16. Unit Test Fixtures :users def test_unique_name user = User.new(:name => user(:mahesh).name, :email => “umamahesh_nyros@yahoo.com&quot; , :mobilenum => 9866439593, :image_url => &quot;fred.gif&quot; ) assert !user.save assert_equal &quot;has already been taken&quot; , user.errors.on(:name) end

17. Unit test supports assert(boolean,message) assert_equal(expected, actual,message) assert_not_equal(expected, actual,message) assert_nil(object,message) assert_not_nil(object,message) assert_match(pattern, string,message) assert_no_match(pattern, string,message)

18. Functional Testing of Controllers require ‘user_helper’ def UserTest < Test::Unit::Testclass def test_index assert true end end

19. Functional Testing of Controllers myapp > ruby test/functional/user_test_controller.rb Loaded suite test/functional/ user_test_controller.rb Started . Finished in 0.0604571 seconds. 1 tests, 1 assertions, 0 failures, 0 errors

20. Thank You