Effective Testing with RSpec 3

Sharing Common Logic

Over the past several chapters, you’ve used several different techniques to share common setup logic.

The main three organization tools are let definitions, hooks, and helper methods. Here’s a snippet that contains all three of these items side by side. It’s a stripped-down version of the API specs you wrote for Chapter 5, ​Testing in Isolation: Unit Specs​, including a minor refactoring from the exercises.

07-structuring-code-examples/03/expense_tracker/spec/api_spec.rb

RSpec.describe 'POST a successful expense' do
  # let definitions
  let(:ledger)  { instance_double('ExpenseTracker::Ledger') }
  let(:expense) { { 'some' => 'data' } }

  # hook
  before do
    allow(ledger).to receive(:record ...