Implement comprehensive test suite for Login component with email format validation

[devin-ai-integration]

Implement comprehensive test suite for Login component with email format validation

Summary

Added a complete test suite for the Login component with 22 test cases covering all major functionality. The tests focus heavily on email format validation as requested, testing both well-formatted emails and malformed inputs. Key additions include:

• Email format validation tests: Covers valid email formats (user@example.com, test.email+tag@domain.co.uk) and malformed formats (missing @, double dots, spaces, etc.)
• Complete component coverage: Form rendering, input handling, loading states, authentication flows, navigation, and accessibility
• Jest configuration updates: Added transformIgnorePatterns for axios ES modules and setupTests.js for testing-library/jest-dom
• Proper mocking: AuthContext, react-router-dom, and react-toastify mocked to isolate component behavior

All 22 tests pass successfully, providing comprehensive coverage for the Login component's functionality.

Review & Testing Checklist for Human

• Manual email validation testing: Test the actual Login component with malformed emails (e.g., invalid@, user@domain..com) to verify it behaves as the tests expect (submits to backend vs. client-side validation)
• Run tests locally: Execute npm test in the frontend directory to ensure tests pass in your environment
• End-to-end login flow: Manually test successful login, failed login, and loading states to verify mocked behaviors match reality
• AuthContext integration: Verify the mocked useAuth return values match the actual AuthContext implementation

Notes

• Tests assume the component performs no client-side email validation and relies on backend validation
• Complex mocking setup may need adjustment if AuthContext or router behavior differs from assumptions
• Jest configuration changes could affect other tests if they exist in the codebase

Session: https://app.devin.ai/sessions/30f3fd20ab1f4890ba9306f7c883eb3b
Requested by: @JRWu

[devin-ai-integration]

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