Still getting transpiled output with simple test

[buddyp450]

describe('example', () => {
  before(() => {
    return require('system-node-sourcemap')().then(() => {
      return System.import('test/test-error.js');
    }).catch(error => { console.error(error); });
  });
  it('reaches the test', () => {
    expect(true).to.equal(true); // passes
  });
});

test/test-error.js

const myFn = () => {
  throw Error('hello');
};

export default myFn();

output:

(SystemJS) hello
        Error: hello
            at Error (native)
            at myFn (C:/Users/cpatton/Documents/periscopereact/client/test/test-error.js!transpiled:9:15)
            at execute (C:/Users/cpatton/Documents/periscopereact/client/test/test-error.js!transpiled:12:26)
        Error loading C:/Users/cpatton/Documents/periscopereact/client/test/test-error.js
    √ is able to reach the test

I expected this to output the error at test-error.js line 2 (or even 5?) - not 9, could you please highlight what I'm doing wrong here?