jest.config.ts

// MIT License
//
// Copyright Inrupt Inc.
//
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import nextJest from "next/jest";
import type { Config } from "jest";

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

// Add any custom config to be passed to Jest
const customJestConfig: Config = {
  preset: "ts-jest",
  testEnvironment: "jest-environment-jsdom",
  setupFilesAfterEnv: ["<rootDir>/jest.setup.ts"],
  moduleDirectories: ["node_modules", "<rootDir>/"],

  // Exclude the e2e tests:
  modulePathIgnorePatterns: ["e2e"],

  // In CI, we can use 100% of the available resources:
  maxWorkers: process.env.CI ? "100%" : "50%",
  // Automatically clear mock calls and instances between every test
  clearMocks: true,

  // Collect coverage metrics:
  collectCoverage: true,
  coverageDirectory: "coverage",
  // This enables usage with Sonarcloud's code coverage tooling:
  coverageReporters: process.env.CI ? ["text", "lcov"] : ["text"],

  coveragePathIgnorePatterns: [
    "/node_modules/",
    "e2e/",
    ".*.mock.tsx",
    "pages/",
  ],

  // Github-Actions reporter in CI:
  reporters: process.env.CI ? ["github-actions", "default"] : ["default"],

  // Required by the React testing library
  injectGlobals: true,
};

async function jestConfig() {
  const nextJestConfig = await createJestConfig(customJestConfig)();

  // Remove the ignore for /node_modules/ this allows Jest to transpile ESM
  // modules for use from CommonJS which is necessary until Jest fully supports ESM:
  // https://github.com/vercel/next.js/issues/40183
  // https://github.com/vercel/next.js/blob/v15.1.4/packages/next/src/build/jest/jest.ts#L175-L176
  nextJestConfig.transformIgnorePatterns =
    nextJestConfig.transformIgnorePatterns?.filter(
      (pattern: string) => !pattern.startsWith("/node_modules/"),
    );

  return nextJestConfig;
}

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