test-mock-prefix

a module-scope mock variable without the `mock` prefix Jest hoisting needs

Deterministic checkblocking by defaultbasetests

The argument

Mocks

Place mock declarations and jest.mock() blocks after the imports, marked with a // Mocked Imports header and // ------------------------- separators between groups (mirror any existing test file's formatting).
Mock variables must be prefixed mock — Jest hoists jest.mock() calls to the top of the file, and only mock-prefixed variables are accessible inside the factory.
Set mock return values inside the setup() factory — never in a beforeEach.
Do NOT mock modules that only export plain constants — import the real module; mocking it blocks coverage and adds no isolation. Mock a constant module only if it has import-time side effects or the test needs a different value (prefer jest.replaceProperty or injection).
Scope strategy: inline mocks for one file; a co-located __mocks__/ folder when multiple tests in the area share a mock; test/mocks/ (with test/fixtures/, test/utils/) for codebase-wide utilities.

The proof

failsubject.unit.test.ts

import { expect, describe, test, jest } from '@jest/globals';

const getProfile = jest.fn<() => string>();

describe('subject', () => {
	test('reads the profile', () => {
		getProfile.mockReturnValue('p.png');

		expect(getProfile()).toBe('p.png');
	});
});

passsubject.unit.test.ts

import { expect, describe, test, jest } from '@jest/globals';

const mockGetProfile = jest.fn<() => string>();

const setupProfile = () => {
	const getGravatar = jest.fn<() => string>();

	mockGetProfile.mockReturnValue('p.png');
	getGravatar.mockReturnValue('g.png');

	return { getGravatar };
};

describe('subject', () => {
	test('reads the profile', () => {
		const { getGravatar } = setupProfile();

		expect(mockGetProfile() + getGravatar()).toBe('p.pngg.png');
	});
});

Turn it down

Both lines go in your lightsout.config.json.

"standards-checks": { "test-mock-prefix": "advisory" }

"standards-checks": { "test-mock-prefix": "off" }