Unit Testing with RSpec

Clinic overview

In this clinic, we will go over:

• Setting up RSpec
• TDD workflow - why we test!
• Build classes using Test Driven Development
• Resource for good practices for writing rspec tests

##Getting RSpec Set Up

• gem install rspec
• In the project root set up the following file structure:

• spec/lib/class_spec.rb
• lib/class.rb goes in lib

• Configure RSpec for color tests. In the root folder touch .rspec and insert "--color" "--fail-fast"
• To reference our classes, our tests need require_relative '../../lib/class.rb'
• We can set up a spec_helper to make sure all of our classes are referenced when running tests.

##TDD workflow

• Why tests?
• Write tests - thinking through all of our use cases.
• Get a failing test suite
• Let failing tests guide our code development
• Do the simplest thing to get the test to pass
• Refactor

##Building Classes with TDD

• Dice object, with state of sides and behavior of rolling.
• Pokemon objects, with states and behavior such as name, ability, strength, attack, evolve, etc.

###Start with a Test

• Start building our first tests
  • require_relative '../lib/dice.rb'
• Let's describe our Dice class.
  • RSpec.describe Dice do standard to start with a describe for the class/ initialize method
  • Method definition in a describe block with ".notation" for class methods and "#notation" for instance methods
  • '.new' constructor, class method
  • '#roll' instance method
• Let's build out our Pokemon class.
  • Constructor, initialize method: name, ability, birthday
  • add a hit_points with a default value
  • add a strength counter
  • add behavior for training
  • add behavior for attacking
  • add behavior for checking if a pokemon is ready to evolve
  • add behavior for checking if a pokemon alive
• Refactoring
  • We can refactor our tests (e.g move the let(:pokemon) up to the top to have access to all)
  • We can look back at our code and refactor methods and run the test suite to make sure it passes our intended outcomes.