jest.config.js

const { pathsToModuleNameMapper } = require('ts-jest/utils');

const { compilerOptions } = require('./tsconfig.json');
const paths = pathsToModuleNameMapper(compilerOptions.paths, { prefix: '<rootDir>/' });

module.exports = {
  globals: { __PATH_PREFIX__: '' },
  moduleNameMapper: {
    '.+\\.(css|styl|less|sass|scss)$': 'identity-obj-proxy',
    '.+\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$':
      '<rootDir>/__mocks__/file-mock.js',
    '^gatsby-core-utils/(.*)$': 'gatsby-core-utils/dist/$1', // Workaround for https://github.com/facebook/jest/issues/9771
    '^gatsby-page-utils/(.*)$': 'gatsby-page-utils/dist/$1', // Workaround for https://github.com/facebook/jest/issues/9771
    '^gatsby-plugin-utils/(.*)$': ['gatsby-plugin-utils/dist/$1', 'gatsby-plugin-utils/$1'], // Workaround for https://github.com/facebook/jest/issues/9771
    ...paths,
  },
  setupFiles: ['<rootDir>/loadershim.js'],
  testPathIgnorePatterns: ['node_modules', '\\.cache', `<rootDir>.*/public`],
  testURL: 'http://localhost',
  transform: { '^.+\\.[jt]sx?$': '<rootDir>/jest-preprocess.js' },
  transformIgnorePatterns: ['node_modules/(?!(gatsby)/)'],
};