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Back-end Engineering

Isolating Dependencies using JUnit and Mockito

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.

JUnit

Kotlin

Mockito

See path

5 lessons

26 practices

3 hours

Programming, Algorithms, and Data Structures

Lessons and practices

Lesson 1: Introduction to Dependencies in Testing with Kotlin

Email Service Validation with TDD

Implementing LogSeverity in EmailService

Debugging and Fixing Unit Tests in EmailService

Creating Dummies for Dependencies in EmailService

Implementing Test Doubles with Interfaces in NewsletterService

Lesson 2: Introduction to Stubs in Testing with Kotlin

Weather Alert Service Simulation Task

Weather Alert Service Implementation and Testing

Replacing Stub with Mockito Mock in WeatherAlertService

Handling Storm Alerts in WeatherAlertService

Weather Alert System Testing with Stubs in Kotlin

Refactor WeatherData with Condition Enum in Kotlin

Lesson 3: Integrating Spies in Test-Driven Development with Kotlin

Verify Interaction with Notification Service

Handling Urgent Notifications in NotificationService

Setting Up Spies for NotificationService Priority Testing

Testing NotificationService with Mockito in Kotlin

Lesson 4: Integrating Mocks in Test-Driven Development with Kotlin

Using Mocks in Unit Tests to Isolate Dependencies in Kotlin

Mocking Exchange Rate Service in Kotlin

Verify Exception Handling for Negative Price Conversion in PricingService

Creating Custom Mocks with Mockito in Kotlin

Writing Tests for calculateBulkPrices Method in PricingService Class

Lesson 5: Introduction to Fakes in TDD with Kotlin

Implement User Registration Logic Using In-Memory Repository in Kotlin

Preventing Duplicate Email Registration in User Service

Update User Name Functionality in UserService

Handling Non-Existent User Updates in UserService

Implementing User Deactivation in Kotlin

Test-Driven Development: Implement User Deactivation

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