write unit test for saving data into db

Question

require_relative File.expand_path '../../test_helper',__FILE__

FactoryGirl.define do
  factory :task do
    name "testinga again"
    finished  0
  end
end


class TaskTest < Test::Unit::TestCase

  include FactoryGirl::Syntax::Methods

  test "should not save tasks without title" do
    task = Task.new
    assert_equal false, task.save
  end

  test "should save tasks" do
    task = FactoryGirl.create(:task)
    assert_equal attributes_for(:task), task
  end  

end

I want to unit test the task creation process. In the should save task task, I have saved the value into the db, now I want to test if the saved value is equal to what i really sent to the db. How to do that or Am i even doing it right?

Answer 1

First of all, you are trying to check stuffs that are already been tested by industry leading engineers. If you see the ActiveRecord project, every API has been tested rigorously. So I recommend you skip this.

But, if your purpose is to learn UnitTesting, then again you are doing it wrong. Unittesting is a black-box testing. You are not supposed to call/invoke any other classes or third party softwares/services like Database in your case.

Lets call this a Integration Test.

---

I want to test if the saved value is equal to what i really sent to the db

Its easy; see:

  test "should save tasks" do
    task = FactoryGirl.build(:task, name: 'John')
    task.save
    assert_equal 'John', task.reload.name
  end 

reload fetches the record from the database.