title: Testing a CLI made with docopt, with unittest
body: <p>There is a part of the code in the file <code>fastq_trimmer.py</code>:  </p>
  
  <pre><code>if __name__ == '__main__':
      usage = '''
      Fastq Trimmer CLI.
  
      Usage:
          fastq_trimmer.py trim &lt;filePath&gt; &lt;trimFactor&gt;
  
      '''
  
      args = docopt(usage)
  
      if args['trim']:
          commenceOperation(args)
      else:
          print(usage)
  </code></pre>
  
  <p>Im trying to write a unittest :  </p>
  
  <pre><code>import fastq_trimmer
  from docopt import docopt
  
  doc = fastq_trimmer.commenceOperation(args)
  
  class TestTrimmer(unittest.TestCase):
  
      def test_exceptions(self):
          args = docopt(doc, ["/home/eliran/Desktop/example.fastq", "5"])
          self.assertEqual(args["&lt;filePath&gt;"], "/home/eliran/Desktop/example.fastq")
          self.assertEqual(args["&lt;trimFactor&gt;"], "5")
  </code></pre>
  
  <p>basically im trying to control the args variable from the unittest file so I can 'inject' the CLI with the args i specify in the unittest file.</p>