new_contents: import lldb
  from lldbtest import *
  import lldbutil
  import os
  import unittest2
  import sys
  import pexpect
  
  class PExpectTest(TestBase):
      
      mydir = TestBase.compute_mydir(__file__)
  
      def setUp(self):
          # Call super's setUp().
          TestBase.setUp(self)
  
      def doTest(self):
          # put your commands here
          pass
  
      def launchArgs(self):
          return ""
  
      def launch(self):
          self.timeout = 5
          self.child = pexpect.spawn('%s %s' % self.lldbHere, self.launchArgs())
  
      def expect(self, patterns=None, timeout=None):
          if patterns is None: patterns = '.*'
          return self.child.expect(patterns, timeout=timeout)
  
      def sendimpl(self, sender, command, patterns=None, timeout=None):
          if timeout is None: timeout = self.timeout
          sender(command)
          if patterns is not None: return self.expect(patterns=patterns, timeout=timeout)
          return None
  
      def send(self, command, patterns=None, timeout=None):
          self.sendimpl(self.child.send, command, patterns, timeout)
  
      def sendline(self, command, patterns=None, timeout=None):
          self.sendimpl(self.child.sendline, command, patterns, timeout)
  
      def quit(self, gracefully=None):
          if gracefully is None: gracefully = True
          self.child.sendeof()
          self.child.close(force=not gracefully)
          self.child = None
  
subject: Add an helper class to write pexpect-based test cases Over time, we should improve this class and port all pexpect based testing over to using this