cat > jest.config.js <<'JS'
const nextJest = require("next/jest");

const createJestConfig = nextJest({ dir: "./" });

const customJestConfig = {
  testEnvironment: "jsdom",
  setupFilesAfterEnv: ["<rootDir>/jest.setup.js"],
};

module.exports = createJestConfig(customJestConfig);
JS

cat > jest.setup.js <<'JS'
import "@testing-library/jest-dom";
JS