Unit & System Testing Mastery: Practical Testing for JS/TS, PHP, React Native, and Java Applications

Duration 4 days – 28 hrs

 

Overview

 

This training equips participants with the skills to design, implement, and maintain effective unit tests and system tests for modern applications. It covers testing principles, test design techniques, mocking/stubbing, test automation fundamentals, and test execution strategies aligned to real-world development workflows.

 

The course is hands-on and maps to your existing technologies—JavaScript/TypeScript (web), PHP (backend), React Native (mobile apps), and Java (desktop apps)—so participants can immediately apply best practices to current projects and improve software quality, stability, and delivery speed.

 

Objectives

 

• Understand the difference between unit, integration, system, and acceptance testing
• Write maintainable unit tests using best practices and naming conventions
• Apply test design techniques (equivalence partitioning, boundary value analysis, decision tables)
• Use mocking and stubbing to isolate code and test reliably
• Build a system testing approach aligned with business workflows
• Plan test scenarios, test cases, and test suites for system-level validation
• Execute tests efficiently and interpret results (coverage, defects, stability)
• Integrate testing into development lifecycle (shift-left) and CI pipelines (overview)
• Improve test quality through structured refactoring and test maintenance practices

 

Audience

 

• Web developers using JavaScript/TypeScript and PHP
• Mobile developers using React Native
• Desktop application developers using Java
• QA engineers / test analysts transitioning into automation
• Team leads, tech leads, and developers responsible for quality assurance
• Product teams who want to improve defect prevention and release readiness

 

Prerequisites 

• Basic programming knowledge (any language)

• Familiarity with web/mobile/desktop application concepts

• Basic understanding of functions, classes, and APIs

• Optional but helpful: experience working with Git and a code repository

Course Content

 

Day 1 — Testing Foundations + Unit Testing Essentials

 

Testing Fundamentals (Concepts & Strategy)

 

• Why testing matters: cost of defects, faster releases, confidence in change
• Testing levels:
  • Unit vs Integration vs System vs UAT
• Testing in SDLC (Shift-left testing & modern Agile testing mindset)
• Writing testable code (high-level principles)
  • single responsibility
  • separation of concerns
  • pure functions
• Common testing terminology
  • test suite, test case, assertion, fixture, test doubles

 

Unit Testing Principles & Best Practices

 

• What makes a good unit test
  • fast, isolated, repeatable, readable
• AAA pattern (Arrange–Act–Assert)
• Given–When–Then style
• Naming conventions and structuring test files
• Test data preparation strategies

 

Hands-on Lab (General):

• Write unit tests for simple business functions (calculator, validation, rules engine)

 

Day 2 — Unit Testing Implementation + Mocking & Test Design

 

Unit Testing in Your Technology Stack (Mapped)

JavaScript/TypeScript

 

• Unit testing workflow (typical tool examples: Jest/Vitest)
• Testing functions, modules, utilities
• Testing React components at unit level (component behavior + props)

PHP

• Unit testing workflow (typical tool examples: PHPUnit)
• Testing service classes and business logic layers

Java (Desktop)

• Unit testing workflow (typical tool examples: JUnit)
• Testing class behaviors and logic components

 

Mocking, Stubbing, and Test Doubles

 

• When and why mocking is needed
• Mock vs Stub vs Spy vs Fake
• Avoiding fragile tests (over-mocking)
• Testing external dependencies:
  • API calls
  • database access
  • file system
  • time/date dependencies

 

Test Design Techniques (To Increase Coverage Smartly)

 

• Equivalence Partitioning
• Boundary Value Analysis
• Decision Tables
• State-based testing (basic)
• Handling negative testing and edge cases

 

Hands-on Lab (Stack-Based):

• Add mocks for API/database calls
• Improve weak tests with boundary cases and decision tables

 

Day 3 — System Testing Approach + End-to-End Validation

 

System Testing Concepts

 

• What system testing validates (functional + non-functional)
• System testing vs Integration testing
• Testing business workflows end-to-end
• System test planning and execution:
  • smoke testing
  • regression testing
  • sanity testing
• Test environments: dev/test/staging/prod (overview)

 

Building System Test Scenarios & Test Suites

 

• Translating requirements → test scenarios
• Writing effective test cases
  • steps, expected results, preconditions
• Defect lifecycle (basic):
  • logging defects
  • severity vs priority
  • reproducibility and evidence gathering

 

Intro to Automated System Testing (Tool-Agnostic)

 

(Focused on patterns, not tool overload)

• What can be automated vs what should remain manual
• UI-based system testing: web + mobile + desktop concepts
• API-level system testing: validating services and responses
• Test reporting and basic metrics
  • pass rate
  • defect trends
  • test coverage awareness

 

Capstone Activity (Group or Individual):
Create a mini Unit + System Test Pack for a sample system (or your internal app):

• Unit test suite (10–15 tests)
• System test scenarios (8–12 scenarios)
• Defect report template + test execution report