title: Gulp sass failing silently
body: <p>I have a very simple gulp task for transforming scss into css files:</p>
  
  <pre><code>function css() {
    return gulp.src('src/scss/_index.scss')
      .pipe(sass().on('error', sass.logError))
      .pipe(gulp.dest('public/css'))
  }
  </code></pre>
  
  <p>As you probably imagine, <code>_index.scss</code> mostly imports other files.</p>
  
  <p>Now, if I comment out line number 3, the code does what it's supposed to: it copies <code>_index.scss</code> to <code>public/css</code>. But with line 3 it produces no output whatsoever, without printing any errors to the console. All I get is:</p>
  
  <pre><code>[0] [17:32:46] Starting 'css'...
  [0] [17:32:46] Finished 'css' after 79 ms
  </code></pre>
  
  <p>How can I even inspect what might be an issue here? The sass file is correct, as before that I would compile it without using gulp.</p>