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Back-end Engineering

Refactoring by Leveraging Tests with Kotlin & JUnit

This course focuses on the Refactor step in TDD, teaching developers to spot code smells and resolve them through refactoring. Using real-world examples, you'll identify common issues, apply refactoring techniques, and ensure functionality is preserved with existing tests.

JUnit

Kotlin

See path

5 lessons

21 practices

3 hours

Computer Science Fundamentals

Lessons and practices

Lesson 1: Eliminating Duplicate Code and Magic Numbers with Kotlin

Refactoring Test Code for Maintainability in ShoppingCartTest

Refactor Test Cases Using Parameterized Tests in ShoppingCartTest Suite

Refactor the ShoppingCart to Eliminate Duplication

Refactor ShoppingCart to Eliminate Loop Duplication

Refactor ShoppingCart by Removing Magic Numbers

Lesson 2: Refactoring Long Methods in Kotlin with Extract Method Technique

Refactor User Validation Logic in UserRegistrationService

Refactor Address Validation to AddressValidator Class

Refactor User Registration for Data Normalization

User ID Generation and Registration Service Refactoring Task

Lesson 3: Refactoring Complex Function Signatures with Parameter Objects in Kotlin

Refactor to Use ScoreWeights Parameter Object

Parameter Object Refactoring for Exam Score Processing Task

Refactor and Reorder Method Parameters for Clarity and Cohesion

Refactoring Method with Default Parameters in Kotlin

Lesson 4: Refactoring Feature Envy in Kotlin with the Move Method Technique

Refactoring Feature Envy in Kotlin Classes

Refactor CalculateFinalGrade Method to Student Class

Refactor getFailedAssignments Method in Student Class

Refactoring Feature Envy: Extracting StudentGradeCollection Class

Lesson 5: Addressing Large Classes with the Extract Class Pattern in Kotlin

Refactoring Shopping Cart for Single Responsibility Principle

Enhancing ShoppingCart with PriceCalculator Refactoring

Refactoring ShoppingCart with DiscountCalculator in Kotlin

Implement Unit Tests for DiscountCalculator and PriceCalculator

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