jest.config.js

module.exports = {
  preset: 'ts-jest/presets/js-with-babel',
  testEnvironment: 'jsdom',
  testEnvironmentOptions: {
    customExportConditions: ['node']
  },
  moduleNameMapper: {
    '^[./a-zA-Z0-9$_-]+\\.ttl$': '<rootDir>/__mocks__/fileMock.js',    // '\\.ttl$'
  },
  collectCoverage: true,
  // For some reason Jest is not measuring coverage without the below option.
  // Unfortunately, despite `!(.test)`, it still measures coverage of test files as well:
  forceCoverageMatch: ['./src/**/*!(.test).ts'],
  // Since we're only measuring coverage for TypeScript (i.e. added with test infrastructure in place),
  // we can be fairly strict. However, if you feel that something is not fit for coverage,
  // mention why in a comment and mark it as ignored:
  // https://github.com/gotwarlost/istanbul/blob/master/ignoring-code-for-coverage.md
  coverageThreshold: {
    global: {
      branches: 10,
      functions: 25,
      lines: 20,
      statements: 20
    }
  },
  setupFilesAfterEnv: ['./jest.setup.ts']
}