Implement Comprehensive Authentication Testing Suite

[devin-ai-integration]

Implement Comprehensive Authentication Testing Suite

Summary

This PR implements a complete authentication testing infrastructure covering both backend and frontend components. The implementation adds 75 total tests (29 backend + 46 frontend) that verify the entire authentication flow from registration to protected route access, including security validation and error handling scenarios.

Backend Testing (29 tests):

• Integration tests covering complete auth flow (register → login → profile)
• Security tests for SQL injection protection, token tampering, and password validation
• Enhanced JWT testing with token lifecycle management

Frontend Testing (46 tests):

• React component tests for Login/Register forms using React Testing Library
• AuthContext state management and API integration testing
• API interceptor tests for token attachment and 401 error handling

Infrastructure Improvements:

• Test utilities and data factories for consistent test data creation
• Enhanced bootstrap utility with multiple user scenarios and flow verification
• Comprehensive test documentation with best practices and security considerations
• Form accessibility improvements with proper label associations

Review & Testing Checklist for Human

Critical items requiring careful verification:

• Security test effectiveness: Manually verify that SQL injection tests in test_auth_security.py actually test meaningful attack vectors and aren't giving false confidence
• Mock accuracy: Compare frontend API mocks in test-utils.js against actual backend responses to ensure they accurately reflect real behavior
• Test isolation: Run backend tests multiple times and verify database cleanup is working properly between tests
• Authentication flow integrity: Manually test the complete auth flow (register → login → dashboard) in the actual application to ensure tests match reality
• Bootstrap utility impact: Verify the enhanced bootstrap script doesn't break existing development workflows

End-to-End Test Plan

1. Start the backend server and run the enhanced bootstrap script to verify auth flow testing
2. Run frontend tests and compare error scenarios against actual API responses
3. Test security scenarios manually (try actual SQL injection attempts on registration/login)
4. Verify that 401 responses properly trigger logout in the browser application
5. Check that test documentation matches actual test implementation

Notes

Requested by: @JRWu
Link to Devin run: https://app.devin.ai/sessions/ba4bd9e5c6484392aaa8c066b768b4b8

Key Implementation Details:

• Uses in-memory SQLite for fast backend test execution
• Frontend tests use React Testing Library with comprehensive user interaction simulation
• Security tests include token tampering, SQL injection, and password strength validation
• All tests are designed to be independent with proper setup/teardown

Warning: This is a large PR (17 files, 3,365 insertions) - the extensive changes increase the likelihood of subtle bugs that may not be immediately apparent.

[devin-ai-integration]

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[sonarqubecloud]

Quality Gate failed

Failed conditions
31 Security Hotspots
12.7% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud