jest.config.js

module.exports = {
  collectCoverageFrom: [
    "**/*.{js,jsx,ts,tsx}",
    "!**/*.d.ts",
    "!**/node_modules/**",
  ],
  setupFilesAfterEnv: ["<rootDir>/setupTests.js"],
  testPathIgnorePatterns: ["/node_modules/", "/.next/"],
  transform: {
    "^.+\\.(js|jsx|ts|tsx)$": "<rootDir>/node_modules/babel-jest",
    "^.+\\.css$": "<rootDir>/config/jest/cssTransform.js",
  },
  transformIgnorePatterns: [
    "/node_modules/",
    "^.+\\.module\\.(css|sass|scss)$",
  ],
  moduleNameMapper: {
    "^.+\\.module\\.(css|sass|scss)$": "identity-obj-proxy",
  },
  //additional prop from a github issue: https://github.com/zeit/next.js/issues/8663
  preset: "ts-jest",
  testEnvironment: "jsdom",
  globals: {
    // we must specify a custom tsconfig for tests because we need the typescript transform
    // to transform jsx into js rather than leaving it jsx such as the next build requires.  you
    // can see this setting in tsconfig.jest.json -> "jsx": "react"
    "ts-jest": {
      tsConfig: "tsconfig.jest.json",
    },
  },
};