example.test.tsx

import { it, expect } from "@jest/globals";
import { render } from "@testing-library/react";
import events from "@testing-library/user-event";

import { BrowserRouter } from "react-router-dom";
import { MemoryRouter } from "react-router";
import { Provider } from "react-redux";

import { initStore } from "./store";
import { Application } from "./Application";

it('по адресу /about должна открываться страница "о проекте"', () => {
  const store = initStore();
  const application = (
    <MemoryRouter initialEntries={["/about"]} initialIndex={0}>
      <Provider store={store}>
        <Application />
      </Provider>
    </MemoryRouter>
  );

  const { getByTestId } = render(application);

  expect(getByTestId("page-title").textContent).toEqual("About");
});

it("если добавить элемент, он появляется в списке", async () => {
  const store = initStore();
  const application = (
    <BrowserRouter>
      <Provider store={store}>
        <Application />
      </Provider>
    </BrowserRouter>
  );

  const { getByTestId, getAllByTestId } = render(application);

  await events.type(getByTestId("input-add"), "Сделать домашку");

  await events.click(getByTestId("button-add"));

  const items = getAllByTestId("list-item");

  expect(items.map((el) => el.textContent)).toContain("Сделать домашку");
});