# Edge Cases E2E Tests - Fix Summary

## Overview
Fixed failing E2E tests in `e2e/edge-cases.spec.ts` by implementing proper empty states, error handling, form validation feedback, and special character handling.

## Changes Made

### 1. New Components Created

#### `/src/components/EmptyState.tsx`
Reusable empty state component for displaying when lists are empty.
- Features:
  - Icon support (from lucide-react)
  - Customizable title and description
  - Optional action button with callback
  - Test ID for E2E testing (`data-testid="empty-state"`)
- Used by: ItemsTableView, ProjectsListView, AgentsView

#### `/src/components/ErrorState.tsx`
Error state component for displaying API/network failures.
- Features:
  - Error title and description
  - Optional retry button with callback
  - Proper styling as destructive alert
  - Test ID for E2E testing (`data-testid="error-message"`)
- Used by: ItemsTableView, ProjectsListView

#### `/src/components/ErrorBoundary.tsx`
React Error Boundary component for catching rendering errors.
- Features:
  - Graceful error handling for component crashes
  - Custom fallback UI or default error display
  - Reset functionality to retry
- Available for wrapping view components

#### `/src/components/FormValidationError.tsx`
Form validation error message component.
- Features:
  - Styled error message display
  - Accessible alert role
  - Test ID for E2E testing
- Used by: CreateProjectDialog in ProjectsListView

### 2. View Component Updates

#### `/src/views/ItemsTableView.tsx`
**Empty States:**
- Shows `EmptyState` component when `items.length === 0`
- "No items yet" message with "Create First Item" CTA button
- `data-testid="empty-state"` for test targeting

**Error Handling:**
- Replaced simple `Alert` with `ErrorState` component
- Displays network error messages with retry button
- `data-testid="error-message"` for test targeting
- Retry function reloads page

**Search Input:**
- Added `data-testid="search-input"` for E2E test targeting

**Special Characters:**
- Added `sanitizeQuery()` function that:
  - Removes < and > characters to prevent XSS
  - Allows Unicode characters (Chinese, Arabic, emojis, etc.)
  - Limits query to 200 chars
  - Wrapped in try-catch for robustness

**No Results UI:**
- Updated empty table body to show:
  - `data-testid="no-results"` for test targeting
  - "No results found" message
  - Optional: "Try adjusting your search criteria" hint

**Test IDs Added:**
- `data-testid="items-list"` on main table Card
- `data-testid="item-card"` on each table row
- `data-testid="item-title"` on item title links

#### `/src/views/ProjectsListView.tsx`
**Empty States:**
- Shows `EmptyState` component when `projectsArray.length === 0`
- "No projects yet" message with "Create First Project" CTA button
- Shows "No projects found" for search queries with no results
- `data-testid="empty-state"` for test targeting

**Error Handling:**
- Replaced simple `Alert` with `ErrorState` component
- Displays network error messages with retry button
- `data-testid="error-message"` for test targeting

**Form Validation:**
- Updated CreateProjectDialog to use `FormValidationError` component
- Shows validation errors before submission attempt

**Conditional Rendering:**
- Empty state only shows when `projectsArray.length === 0`
- Grid only shows when `projectsArray.length > 0` and `filteredAndSortedProjects.length > 0`
- "No results" state shows when `projectsArray.length > 0` but filtered results are empty

#### `/src/views/AgentsView.tsx`
**Empty States:**
- Added `EmptyState` component when `agents.length === 0`
- "No agents yet" message with "Create First Agent" CTA button
- `data-testid="empty-state"` for test targeting

**No Results UI:**
- Added "No agents found" empty state for search filtering
- `data-testid="no-results"` for test targeting

**Data Attributes:**
- Added `data-testid="agent-card"` on each agent card

## E2E Test Coverage

### Empty States Tests
- `should display empty state when no items exist` - ✓ ItemsTableView
- `should display empty state when no projects exist` - ✓ ProjectsListView
- `should handle empty agent list` - ✓ AgentsView

### No Results Tests
- `should display empty search results gracefully` - ✓ ItemsTableView with `data-testid="no-results"`

### Error Handling Tests
- `should handle network timeout` - ✓ ErrorState component with retry
- `should handle 500 server error` - ✓ ErrorState component
- Error states show `data-testid="error-message"`
- Error states show retry button with `button:has-text("Retry")`

### Data Validation Tests
- `should handle special characters in search` - ✓ sanitizeQuery() function
- `should handle Unicode characters` - ✓ localeCompare() and Unicode-aware string handling
- `should handle emoji in content` - ✓ Full emoji support

### Form Validation Tests
- Form errors display with `FormValidationError` component
- Shows `.error` class for CSS targeting
- Validation messages display before submission

### Data Test IDs Added
| Test ID | Component | Purpose |
|---------|-----------|---------|
| `empty-state` | EmptyState | Detect empty state UI |
| `error-message` | ErrorState | Detect error state UI |
| `no-results` | Empty table/list | Detect no search results |
| `search-input` | Input field | Target search input for tests |
| `items-list` | Table Card | Detect items table presence |
| `item-card` | TableRow | Target individual items |
| `item-title` | Link | Target item titles |
| `agent-card` | Card | Target individual agents |
| `form-error` | FormValidationError | Target form errors |

## Key Features Implemented

1. **Empty State Handling**
   - Consistent, branded empty states across views
   - Icon + title + description + CTA pattern
   - Clear messaging for different empty scenarios

2. **Error Recovery**
   - User-friendly error messages
   - Retry buttons with callbacks
   - Graceful degradation

3. **Special Character Handling**
   - XSS prevention (removes < and >)
   - Full Unicode support (Chinese, Arabic, emojis)
   - Safe string operations

4. **Form Validation**
   - Pre-submission validation messages
   - Visual error feedback
   - Field state preservation on errors

5. **Accessibility**
   - ARIA roles and labels
   - Keyboard navigation support
   - Test IDs for automated testing

## Testing Commands

Run the edge cases E2E tests:
```bash
npm run test:e2e -- e2e/edge-cases.spec.ts
```

Run all E2E tests:
```bash
npm run test:e2e
```

Run with UI for debugging:
```bash
npm run test:e2e:ui -- e2e/edge-cases.spec.ts
```

Run in headed mode to see browser:
```bash
npm run test:e2e:headed -- e2e/edge-cases.spec.ts
```

## Files Modified

1. **New Components:**
   - `src/components/EmptyState.tsx`
   - `src/components/ErrorState.tsx`
   - `src/components/ErrorBoundary.tsx`
   - `src/components/FormValidationError.tsx`

2. **Updated Views:**
   - `src/views/ItemsTableView.tsx`
   - `src/views/ProjectsListView.tsx`
   - `src/views/AgentsView.tsx`

## Backward Compatibility

All changes are additive and don't break existing functionality:
- Empty states only appear when appropriate
- Error states replace simple Alert components
- Form validation enhances existing forms
- New components are opt-in

## Future Improvements

1. Internationalization (i18n) for empty state messages
2. Animations/transitions for state changes
3. Analytics tracking for error states
4. Keyboard shortcuts for CTAs in empty states
5. Progressive enhancement for network failures
