Sometimes they generate double notification
on change:

      1) cli node-sass in.scss should watch the full scss dep tree for a single file (scss):

      Uncaught AssertionError: 'body{background:blue}\n\nbody{background:blue}' == 'body{background:blue}'
      + expected - actual

      -body{background:blue}
      -
       body{background:blue}

      at Socket.<anonymous> (test/cli.js:317:16)
      at readableAddChunk (_stream_readable.js:146:16)
      at Socket.Readable.push (_stream_readable.js:110:10)
      at Pipe.onread (net.js:523:20)

https://github.com/sass/node-sass/issues/1152