Sample gulpfile to blow up gulp-uglify.js

gulpfile.js

'use strict';
var gulp = require('gulp');
var gulpUglify = require('./index.js');
var through = require('through2');

var errorStream = through.obj(function(file, encoding, callback) {
  // Do something improper
  var b = a.c;

  callback();
});

gulp.task('default', function() {
  gulp.src('test/*.js')
      .pipe(gulpUglify())
      .pipe(errorStream);
});