Testing File transport in mocha does not work

[basickarl]

I've looked at your tests for bragi and they do not cover everything. So I tried to cover for example if a log file is actually made when a File transport is added. I checked to see if it worked and apparently it does not. Check below:

test/log.js

'use strict';

import fs from 'fs';
import logger from 'bragi';

// Logging to file.
logger.transports.add(new logger.transportClasses.File({
  filename: 'test.log'
}));

describe('Log', () => {
  it('logger creates a log file when a log is logged', () => {
    logger.log('error', 'test log');
  });
});

test/mocha.opts:

--recursive
--compilers js:babel-core/register
--require babel-polyfill

run via npm test, in the package.json:

"test": "NODE_ENV=test NODE_PATH=\"$(pwd)\" mocha",

As you can see, it outputs via the Console transport:

  Log
[ ✘   error  ] 	test log
  2016-12-09T10:58:26.283Z	 /home/karlm/dev/node/proj/test/log.js:20:21
    ✓ logger creates a log file when a log is logged


  1 passing (26ms)

It however does not create the file test.log.