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Django Test Pattern Examples

This directory contains concrete examples of well-structured Django tests derived from extensive refactoring work in the HI application.

Files

django-test-patterns-examples.py

Comprehensive examples showing:

• CRUD Testing: Real database objects vs mocking
• AJAX/JSON Views: Testing modern async responses
• Form Validation: Complete field requirements and file uploads
• Complex Business Logic: Entity pairings, many-to-many through models
• Session Dependencies: Middleware state requirements
• Synthetic Data: Consistent test data generation
• Error Handling: 404s, validation errors without mocking

Usage

When working on Django tests, refer to these examples to:

1. Avoid anti-patterns like over-mocking database operations
2. Follow established patterns for session setup and form validation
3. Use proper assertions for JSON vs HTML responses
4. Structure test data consistently with synthetic generators
5. Test integration flows rather than just method calls

Key Principles

• ✅ Test real behavior with actual database transactions
• ✅ Use Django's test framework as designed (isolated DB transactions)
• ✅ Test business outcomes not implementation details
• ✅ Follow application patterns for enums, sessions, relationships
• ❌ Don't mock basic CRUD, model relationships, or form processing
• ❌ Don't assume direct relationships - verify through models/admin

Context

These patterns were discovered while converting heavily mocked tests to use real objects, resulting in:

• More reliable tests that catch real bugs
• Better documentation of application architecture
• Easier maintenance and debugging
• Higher confidence in system behavior

Use these examples as templates when writing new tests or refactoring existing ones.