11.10Pattern 9: Error State Testing

Verify the application handles errors gracefully.

Example: Network Error

# Use eval to simulate offline mode
playwright-cli eval "window.navigator.__defineGetter__('onLine', () => false)"
playwright-cli click e11        # "Save" button ref from current snapshot
playwright-cli snapshot
# → Agent verifies: appropriate offline message shown

Example: Server Error

playwright-cli goto https://app.example.com/broken-page
playwright-cli snapshot
# → Agent checks: is there a user-friendly error page (not a raw 500 stack trace)?
playwright-cli screenshot