Testing Carol Wolf Computer Science

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.

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

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

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.

fixtures/books.yml # Read about fixtures at one: isbn: MyString author: MyString title: MyString two: isbn: MyString author: MyString title: MyString

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.

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

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

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 end assert_redirected_to book_path(assigns(:book)) end

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