jest.config.js

module.exports = {
  testEnvironment: "node",
  preset: "ts-jest",
  roots: ["<rootDir>/src"],
  transform: {
    "^.+\\.tsx?$": "ts-jest",
  },
  testRegex: "(/__tests__/.*|(\\.|/)(test|spec))\\.tsx?$",
  moduleFileExtensions: ["ts", "tsx", "js", "jsx", "json", "node"],
  // Setup Enzyme
  snapshotSerializers: ["enzyme-to-json/serializer"],
  setupFilesAfterEnv: ["<rootDir>/setupTests.ts"],
  testPathIgnorePatterns: ["<rootDir>/.next/", "<rootDir>/node_modules/"],
  collectCoverage: false,
  collectCoverageFrom: ["src/**/*.ts", "src/**/*.tsx"],
  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: "<rootDir>/tsconfig.jest.json",
    },
  },
  moduleNameMapper: {
    "\\.(css|less|scss|sss|styl)$": "<rootDir>/node_modules/jest-css-modules",
  },
};