jest.config.mjs

import nextJest from "next/jest.js";

//-configuration object must always be JSON-serializable.
const createJestConfig = nextJest({
  // Provide the path to your Next.js app to load next.config.js and .env files in your test environment
  dir: "./",
});

// 👇 Setup overlap for both the ssr & csr testing
/** @type {import('jest').Config} */
const sharedConfig = {
  setupFilesAfterEnv: ["<rootDir>/jest.setup.js"],
  transform: { "^.+\\.ts?$": "ts-jest" },
  coveragePathIgnorePatterns: ["<rootDir>/node_modules/"],
  preset: "ts-jest",
};
//👇 Setup for testing client side rendered components
const clientTestConfig = {
  ...sharedConfig,
  testEnvironment: "jest-environment-jsdom",
  testMatch: ["**/__tests__/*.test.tsx", "**/__tests__/page-*"],
};
//👇 Setup for testing server side rendered components
const serverTestConfig = {
  ...sharedConfig,
  testEnvironment: "jest-environment-node",
  testMatch: ["**/__tests__/*.server.test.tsx"],
};

const config = {
  projects: [
    await createJestConfig(clientTestConfig)(),
    await createJestConfig(serverTestConfig)(),
  ],
  silent: true,
  preset: "ts-jest",
  verbose: true,
  automock: true,
};

//createJestConfig is exported this way to ensure that next/jest can load the Next.js config which is async
export default config;