Issue description:
When running command npm run test on my computer (Win10), the testing process aborted due to the unrecognized 'TZ' argument (see the attachment file)

Solution:
Add cross-env as a dev-dependency would solve this incompatibility issue. After its installation, the original 'test' script need to be updated like this:

{
    // ...
    "scripts": {
        "test": "cross-env TZ=America/Los_Angeles mocha 'test/**/*-test.js' && eslint src test",
    // ...
}

Then rerun the test, everything get back to normal.