jest preset example

babelTransform.js

const babelJest = require('babel-jest');

module.exports = babelJest.createTransformer({
  presets: [require.resolve('babel-preset-react-app')],
  babelrc: false,
  configFile: false,
});

cssTransform.js

module.exports = {
  process() {
    return 'module.exports = {};';
  },
  getCacheKey() {
    // The output is always the same.
    return 'cssTransform';
  },
};

jest.config.js

export default () => {
  return {
    roots: ['<rootDir>/src'],
    moduleDirectories: ['node_modules'],
    setupFiles: [require.resolve('react-app-polyfill/jsdom')],
    testEnvironment: 'jest-environment-jsdom-sixteen',
    testMatch: [
      '<rootDir>/src/**/__tests__/**/*.{js,jsx,ts,tsx}',
      '<rootDir>/src/**/*.test.{js,jsx,ts,tsx}',
    ],
    transform: {
      '^.+\\.(js|jsx|mjs|cjs|ts|tsx)$': require.resolve('./babelTransform'),
      '^.+\\.css$': require.resolve('./cssTransform'),
    },
    transformIgnorePatterns: [
      '[/\\\\]node_modules[/\\\\].+\\.(js|jsx|mjs|cjs|ts|tsx)$',
      '^.+\\.module\\.(css|sass|scss)$',
    ],
    moduleNameMapper: {
      '^src/(.*)$': '<rootDir>/src/$1',
    },
    moduleFileExtensions: ['ts', 'tsx', 'js', 'json', 'node'],
    collectCoverageFrom: [
      'src/**/*.{js,jsx,ts,tsx}',
      '!src/**/*.d.ts',
      '!src/index.ts',
      '!src/Plugin.tsx',
      '!src/setupTests.ts',
      '!src/types/**/*.ts',
    ],
    watchPlugins: ['jest-watch-typeahead/filename', 'jest-watch-typeahead/testname'],
    resetMocks: true,
  };
};