Isolating Dependencies with Test Doubles with Swift & XCTest

Overview

Discover the pivotal role of test doubles in modern software testing. This introductory session will guide you through the essentials of dummies, stubs, spies, mocks, and fakes. Learn how these powerful tools help you isolate units under test, control behavior, and build reliable, fast, and maintainable tests. Step into the world of test doubles and elevate your software development skills.

Syllabus

Unit 1: Introduction to Dependencies in Testing with Swift

Understanding EmailService with Dummies in TDD
Enhancing DummyLogger with Severity Parameter in EmailService
Fixing Test Suite for EmailService in Swift
Enhancing EmailService with Dummy Dependencies in Swift
Enhancing NewsletterService with Dummy Dependencies in Swift

Unit 2: Implementing Stubs in Swift with XCTest for Test Driven Development

Using Stubs to Test Weather Alert Service in Swift
Using Stubs to Test Weather Alert Service in Swift
Using Stubs to Test Storm Warnings in Weather Alert Service
Using Stubs to Test Weather Alert Service in Swift
Refactoring Weather Alert Service to Use MockWeatherService in Swift

Unit 3: Integrating Spies into Test-Driven Development with Swift and XCTest

Verifying Notification Sending with Spies in Swift
Verifying and Handling Urgent Notifications in Swift
Verifying and Handling Medium-Priority Notifications in Swift
Verifying Multiple User Notifications with Spies in Swift

Unit 4: Implementing Mocks in Test-Driven Development with Swift and XCTest

Mocking ExchangeRateService in PricingService Tests
Mocking ExchangeRateService to Avoid Unnecessary Calls in PricingService Tests
Mocking ExchangeRateService to Handle Negative Amounts in PricingService Tests
Mocking ExchangeRateService to Handle Different Exchange Rates in PricingService Tests
Mocking ExchangeRateService to Calculate Bulk Prices in PricingService Tests

Unit 5: Implementing Fakes in Test-Driven Development with Swift and XCTest

Implementing User Registration with Fake Repository in Swift
Implementing Duplicate Email Check in User Registration with Fake Repository in Swift
Implementing User Name Update with Fake Repository in Swift
Implementing Error Handling for Non-Existent User Name Update in Swift
Implementing Error Handling for Non-Existent User Deactivation in Swift
Implementing Error Handling for Non-Existent User Deactivation in Swift