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Thoughts, experiences, and insights from my programming journey

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May 13, 2025

Advanced Mocking Strategies and Best Practices

Master advanced mocking techniques for complex Next.js testing scenarios. This comprehensive guide covers conditional mocking, dynamic mock responses, and mock factory functions for reusable test setups. Learn how to handle circular dependencies, event emitters, GraphQL queries, WebSocket connections, and database transactions. Discover time and date mocking strategies, file system operations, and performance API mocking. You'll explore sophisticated patterns for organizing mocks, validating mock calls, and avoiding common pitfalls that create brittle test suites. This post provides the advanced techniques needed to test complex real-world applications with confidence.

testingmockingadvanced-testingnextjsjestcomplex-dependenciescircular-dependenciesgraphql-testingwebsocket-testingdatabase-mockingtime-mockingfile-system-mockingperformance-testingmock-factoriesconditional-mockingtest-organizationbest-practicesjavascripttypescripttest-patterns
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Apr 14, 2025

Component Testing Patterns for Next.js

Master the art of testing components in Next.js applications with this comprehensive guide to component testing patterns. Learn how to effectively test Server Components, Client Components, and Next.js-specific components like navigation and layouts. Discover the right approaches for testing async components, error boundaries, and components with context providers. This post provides practical examples for testing user interactions, form submissions, and component state changes while avoiding common anti-patterns that create brittle tests. You'll learn how to test behavior rather than implementation details and use semantic queries for better accessibility testing.

testingnextjsreactcomponent-testingserver-componentsclient-componentsjesttesting-libraryuser-interactionsform-testingasync-testingerror-boundariescontext-testingaccessibility-testingbest-practicesjavascripttypescripttest-patterns
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Mar 03, 2025

Testing Real Services vs. Mocked Services: The Right Way

Learn the critical decision-making process for testing services in Next.js applications. This comprehensive guide shows you when to test real services with their actual business logic versus when to mock them entirely. Discover the hybrid approach of testing real service logic while mocking external dependencies, and avoid common anti-patterns that create meaningless tests. You'll learn practical patterns for testing business logic services, data transformation services, validation services, and complex service integrations. Master the art of testing what you own while mocking what you don't control.

testingservicesmockingnextjsunit-testingintegration-testingbusiness-logicapi-testingdatabase-testingbest-practicesjavascripttypescripttest-patternsservice-testingdependency-mocking
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Feb 24, 2025

The Global Mock Trap: Why Your Tests Are Brittle

Discover why global mocks are the hidden enemy of reliable testing in Next.js applications. Learn how global mocks create brittle, unpredictable tests that don't actually verify your real code behavior. This post reveals the dangers of the global mock trap and provides practical patterns for writing tests that actually test your implementation, not your mocks. You'll learn when global mocks are acceptable, how to properly mock dependencies, and the key principles for creating maintainable, reliable test suites.

testingjestmockingnextjsunit-testingtest-patternsjavascripttypescriptbest-practicestest-reliability
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Jan 19, 2025

Why Your Next.js Tests Are Failing (And How to Fix Them)

Discover why Next.js tests fail with cryptic errors like "Request is not defined" and "Unexpected token 'export'". Learn the fundamental principles of proper mocking strategy and how to create reliable, predictable tests for Next.js applications. From API route challenges to ES module issues, this guide covers the essential patterns every Next.js developer needs to know for writing tests that actually work.

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