When behavior depends on library primitives (e.g., Radix) and real browser focus/pointer flows (including document.body portals), unit tests that reimplement internal handlers are not enough. Write tests that render the actual component tree and assert user-observable outcomes.

Apply this standard:

• Render the real primitive/component (not a re-copied onOpenChange/handler) and assert the final DOM state (e.g., tooltip open/closed) and/or event delivery.
• Cover both mouse/pointer focus paths and keyboard/a11y paths (e.g., :focus-visible) and keep the expectations aligned to how the product behaves.
• For portal-based content, include a regression test that matches the real DOM topology (focus moving into portal content should not trigger the incorrect “retract” behavior).

Example pattern (tooltip cancellation):

// Pseudocode: render actual TooltipPrimitive-based component
render(
  <TooltipRoot /* real component */>
    <TooltipTrigger asChild>
      <button>Tip</button>
    </TooltipTrigger>
    <TooltipContent>...</TooltipContent>
  </TooltipRoot>
)

// Mouse/focus path should NOT open
userEvent.click(screen.getByRole('button', { name: /tip/i }))
expect(screen.queryByText('...')).not.toBeInTheDocument()

// Keyboard focus path SHOULD open
screen.getByRole('button', { name: /tip/i }).focus()
expect(screen.getByText('...')).toBeInTheDocument()

This ensures the test verifies the real cancellation mechanism and prevents regressions involving focus and portal DOM behavior.