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Description
Name for new rule
no-unsettled-absence-query
Description of the new rule
Asserting absence with queryBy* + .not.toBeInTheDocument() immediately after render(), before the component has settled, can produce a false positive. The element isn't there yet, not because it won't be there. The community calls this Testing Ghosts.
Testing Library's render() does flush the initial synchronous render (it's wrapped in act() internally), so for a plain component with no async behavior, checking absence right after render() is technically correct. The problem shows up when the component has async side effects like data fetching, lazy loading, state updates from useEffect, etc. In those cases the UI hasn't finished updating, and the absence check passes vacuously. Since the rule can't know whether a component has async behavior, it flags all unsettled absence assertions and lets the developer confirm intent by adding a settling expression.
This rule would enforce that an absence assertion (expect(screen.queryBy*(...)).not.toBeInTheDocument() / .not.toBeVisible()) must be preceded by a "settling" expression within the test body.
Why existing rules don't cover this:
| Existing Rule | Why it doesn't solve this |
|---|---|
prefer-presence-queries |
Enforces correct query type, but doesn't track timing relative to render |
no-await-sync-queries |
Only flags await directly on sync queries, not timing of assertions |
await-async-queries / await-async-utils |
About promise handling, not assertion ordering |
prefer-find-by |
Simplifies waitFor + getBy -> findBy, doesn't detect premature absence checks |
Related issues: #269, #411, #518 - all adjacent but none address this specific pattern.
Testing Library feature
This rule relates to the absence/presence assertion pattern described in the Appearance and Disappearance guide. Specifically, it enforces correct ordering of queryBy* absence assertions relative to async settling utilities (findBy*, waitFor, act) and sync settling queries (getBy*).
Testing Library framework(s)
All frameworks: React, Angular, Vue, Svelte, etc. The pattern applies anywhere screen.queryBy* + .not.toBeInTheDocument() is used.
What category of rule is this?
Warns about a potential error. Less valuable as an error given the call-out above of vanilla components.
Code examples
Fail:
// Absence assertion before component has settled, "Testing a Ghost"
test('shows no error', () => {
render(<AsyncComponent />);
expect(screen.queryByText('error')).not.toBeInTheDocument();
});
// Absence assertion BEFORE the awai, order matters
test('shows no error', async () => {
render(<AsyncComponent />);
expect(screen.queryByText('error')).not.toBeInTheDocument();
await screen.findByText('loaded');
});
// queryAllBy variant
test('shows no alerts', () => {
render(<AsyncComponent />);
expect(screen.queryAllByRole('alert')).not.toBeInTheDocument();
});
// Absence assertion inside waitFor - passes on first retry, still a ghost
test('shows no error', async () => {
render(<AsyncComponent />);
await waitFor(() => {
expect(screen.queryByText('error')).not.toBeInTheDocument();
});
});Pass:
// findBy* settles the component first
test('shows no error', async () => {
render(<AsyncComponent />);
await screen.findByText('loaded');
expect(screen.queryByText('error')).not.toBeInTheDocument();
});
// waitFor settles the component first
test('shows no error', async () => {
render(<AsyncComponent />);
await waitFor(() => expect(something).toBe(true));
expect(screen.queryByRole('alert')).not.toBeInTheDocument();
});
// act settles the component first
test('shows no error', async () => {
await act(() => render(<AsyncComponent />));
expect(screen.queryByText('error')).not.toBeInTheDocument();
});
// getBy* proves sync render completed
test('shows no error', () => {
render(<Component />);
screen.getByText('visible heading');
expect(screen.queryByText('error')).not.toBeInTheDocument();
});What counts as "settled":
- Any
awaitexpression on a preceding statement — coversfindBy*,waitFor,act, custom async helpers - A
screen.getBy*/screen.getAllBy*call — proves the sync render produced expected output
Matchers checked: .not.toBeInTheDocument(), .not.toBeVisible()
Anything else?
References:
- Testing Library: Appearance and Disappearance guide
- Kent C. Dodds: Common mistakes with React Testing Library
- Gerardo Perrucci: Stop Testing Ghosts
- react-testing-library #865 (vague similarity; in the same realm with component mounting/unmounting states)
Do you want to submit a pull request to make the new rule?
I have a working implementation with full test coverage that I'm happy to submit as a PR if this proposal is accepted.