Fast

It’s easy to overlook the importance of pure speed in the long-term maintenance of a test suite or a TDD practice. In the beginning, there isn’t much difference. When we have only a few methods under test, the difference between one second per test and one-tenth of a second per test is almost invisible. The difference between a one-minute suite and a six-second suite is easier to discern.

Slow test suites hurt us in a variety of ways.

Slow tests cost

There are startup costs. In the sample TDD session we walked through in the chapters “ ...

Introduction

Test-Driven Fable

Test-Driven Development Basics

Test-Driven Rails

Use RSpec to Write Efficient Test Cases in the Rails Application

What Makes a Great Test?

Testing Models

Adding Data to Tests

Using Test Doubles as Mocks and Stubs

Integration Testing with Capybara and Cucumber

Testing JavaScript: Integration Testing

Unit-Testing Javascript

Testing Rails Display Elements

Minitest

Testing for Security

Testing External Services

Troubleshooting and Debugging

Running Tests Faster and Running Faster Tests

Testing Legacy Code

Fast: The Fourth Quality of Valuable Tests

Fast

Slow tests cost