Add extensive unit and component tests covering import/export, settings,
and provider list functionality, advancing to Sprint 2 of test development.
Hook Tests:
- useImportExport (11 tests):
* File selection success/failure flows
* Import process with success/failure/exception paths
* Export functionality with error handling
* User cancellation scenarios
* State management (clear selection, reset status)
* Fake timers for async callback testing
- useSettingsForm (5 tests):
* Settings normalization on initialization
* Language persistence from localStorage
* Field updates with language sync
* Reset functionality with initial language restoration
* Optimization to avoid redundant language changes
Component Tests:
- ProviderList (3 tests):
* Loading state with skeleton placeholders
* Empty state with create callback
* Render order from useDragSort with action callbacks
* Props pass-through (isCurrent, isEditMode, dragHandleProps)
* Mock ProviderCard to isolate component under test
Technical Highlights:
- Fake timers (vi.useFakeTimers) for async control
- i18n mock with changeLanguage spy
- Partial mock of @dnd-kit/sortable using vi.importActual
- ProviderCard render spy for props verification
- Comprehensive error handling coverage
Test Coverage:
✓ 19 new test cases (11 + 5 + 3)
✓ Total: 35 tests passing
✓ Execution time: 865ms
✓ TypeScript: 0 errors
Related: Import/export, settings management, provider list rendering
Sprint Progress: Sprint 1 complete, Sprint 2 in progress (component tests)
