Failing test not failing the build

[mathbruyen]

From travis build:

1) Stream resolver generates difference:

Error: timeout of 2000ms exceeded
at null.<anonymous> (/home/travis/build/3musket33rs/mathsync/javascript/core/node_modules/mocha/lib/runnable.js:139:19)
at Timer.listOnTimeout (timers.js:133:15)

[mathbruyen]

Build fails for tests in error when adding

gulp.on('err', function () {
  process.exit(1);
});

at the end of gulpfile.js. err looks strange as usually error is used.

Then the problem is related to jshint, even with fail reporter build is always successful. Only way found up to now:

.pipe(jshint.reporter('fail')).on('error', process.exit.bind(process, 1))

does the trick.

But it starts to be ugly. The root cause seems the way to call gulp through node, with harmony flag set for one test.