Vitest spyOn method won't work outside of test case scope

Question

I am migrating from Jest to Vitest and found out that most of my spyOn methods aren't working because they are declared outside of the test scope:

const notificationSpy = vi.spyOn(NotificationActions, 'addNotification');

describe('PostboxList', () => {
    const renderComponent = (store: Store) => {
        render(<PostboxList />, {
            store,
        });
    };


    it('the notification is visible when fetching status is HasError', async () => {
        const store = mockStore({
            postbox: {
                documents: {
                    data: [],
                    fetchingStatus: DataFetchingStatus.HasError,
                },
                messages: {
                    data: [],
                    fetchingStatus: DataFetchingStatus.HasError,
                },
            },
        });

        renderComponent(store);

        expect(notificationSpy).toHaveBeenCalledOnce({
            title: 'POSTBOX.ERROR.TITLE',
            text: 'POSTBOX.ERROR.TEXT',
        });
    });
});

Now if I move the declaration of my spyOn method to inside the test scope, the test will pass:

describe('PostboxList', () => {
    const renderComponent = (store: Store) => {
        render(<PostboxList />, {
            store,
        });
    };


    it('the notification is visible when fetching status is HasError', async () => {
        const notificationSpy = vi.spyOn(NotificationActions, 'addNotification');

        const store = mockStore({
            postbox: {
                documents: {
                    data: [],
                    fetchingStatus: DataFetchingStatus.HasError,
                },
                messages: {
                    data: [],
                    fetchingStatus: DataFetchingStatus.HasError,
                },
            },
        });

        renderComponent(store);

        expect(notificationSpy).toHaveBeenCalledOnce({
            title: 'POSTBOX.ERROR.TITLE',
            text: 'POSTBOX.ERROR.TEXT',
        });
    });
});

My test config inside Vite config:

test: {
    globals: true,
    environment: 'jsdom',
    setupFiles: './vitest.setup.ts',
    include: ['**/*.{test, spec}.{ts,tsx,js,jsx}'],
    exclude: [...configDefaults.exclude, 'plop', './vitest.setup.ts'],
    deps: {
        inline: ['vitest-canvas-mock'],
    },
    testTimeout: 10000,
    threads: false,
    alias: tsconfigPaths(),
    mockReset: true,
    restoreMocks: true,
    clearMocks: true,
    css: true,
}

I already tried resetting the mock and the spyOn on beforeEach and afterEach but had no success.

I've researched already but no answers or similar issues were found.

Answer 1

Removing these configs solved the issue:

threads: false,
mockReset: true,
restoreMocks: true,
clearMocks: true,