jest config

jest.config.js

module.exports = {
    testEnvironment: 'node',
    roots: ['<rootDir>/test'],
    testMatch: ['**/*.test.ts'],
    transform: {
        '^.+\\.tsx?$': 'ts-jest',
    },
    // Added so that jest prefer to run tests on files
    // with the *.ts extension instead (see below).
    //   https://stackoverflow.com/a/50145833/10237506
    moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
};