Gulp sass errors silently

Question

I am trying to use gulp-sass to compile my scss files, but for some reason it is failing but not displaying an error message.

This is the command output for gulp styles:

[20:40:04] Requiring external module babel-core/register
[20:40:05] Using gulpfile ~\Documents\Development\Web Applications\webux\webux2\gulpfile.babel.js
[20:40:05] Starting 'styles'...

Here is my gulp task:

gulp.task('styles', () => {
  return gulp.src('app/styles/*.scss')
    .pipe($.sass.sync({
      outputStyle: 'expanded',
      precision: 10,
      includePaths: ['.']
    }).on('error', err => {
      $.util.log(err);
    }))
    .pipe(gulp.dest('./tmp/styles'));
});

I get the same output when using $.sass.logError as the error callback.