Testing

1. Testing Carol Wolf Computer Science

2. Testing built into Rails • Rails comes with three databases. • development • test • production • The test database does not contain your important data. • It can be filled and emptied without causing problems. • Run with rake test. • Described in config/database.yml • yml is short for yaml • yaml stands for yaml ain’t markup language • yaml is simpler than xml • It shares the descriptive purpose of xml • An example is on the next page.

3. development: adapter: sqlite3 database: db/development.sqlite3 pool: 5 timeout: 5000 test: adapter: sqlite3 database: db/test.sqlite3 pool: 5 timeout: 5000 production: adapter: sqlite3 database: db/production.sqlite3 pool: 5 timeout: 5000

4. config/database.yml for MySql development: adapter: mysql2 encoding: utf8 database: name_development pool: 5 username: root password: mypassword socket: /tmp/mysql.sock

5. test folder • Each application has a test folder. • Sub folders • fixtures – used for sample data • functional – tests the controller • integration – tests interacting controllers • performance – benching and profiling • unit – tests for models • The scaffold command populates all the sub folders except for integration. • An example is on the next slide.

6. fixtures/books.yml # Read about fixtures at http://ar.rubyonrails.org/classes/Fixtures.html one: isbn: MyString author: MyString title: MyString two: isbn: MyString author: MyString title: MyString

7. Fixtures • When testing with rake test • Empties test database • Loads fixtures data • Puts fixtures data in a variable for saving • Fixtures are in the form of hashes • Can write: books(:Dickens).title • Fixtures can include ERB • Specific tests can be run using rake test:fixtures, rake test:functionals, etc.

8. Unit Tests • Unit tests are used for models, i.e. database tables. • They contain assertions • assert book.invalid? • assert book.errors[:isbn].any? • The names in quotes will be replaced by names with underscores. require 'test_helper' class BookTest < ActiveSupport::TestCase # Replace this with your real tests. test "the truth" do assert true end end

9. Replace book_test.rb with following: require 'test_helper' class BookTest < ActiveSupport::TestCase # Replace this with your real tests. test “book attributes may not be empty" do book = Book.new assert book.invalid? assert book.errors[:isbn].any? assert book.errors[:author].any? assert book.errors[:title].any? end end

10. Functional tests • Used to test controllers • book_controller_test.rb contains tests for each method in the book controller • Below the test for the create method. • Its parameters are sent with a post method test "should create book" do assert_difference(‘Book.count') do post :create, :book => @book.attributes end assert_redirected_to book_path(assigns(:book)) end

11. Our book_controller_test.rb test "should create book" do assert_difference('Book.count') do post :create, :book => { :isbn => '2345', :title => 'Emma', :author => 'Austen‘ } end assert_redirected_to book_path(assigns(:book)) end