A python lldb extension for easier casting of pointers to Swift types when debugging

test.py

#!/usr/bin/python

import lldb
import commands
import optparse
import shlex
import string

def create_options_parser():
  usage = "usage: %prog [options]"
  description = '''This command takes a variable name, memory address and type name to cast to the correct Swift object type'''

  parser = optparse.OptionParser(description=description, prog='test', usage=usage)
  parser.add_option('-v', '--varname', type='string', dest='var_name', help='name for returned variable')
  parser.add_option('-a', '--address', type='string', dest='address', help='memory address of the object')
  parser.add_option('-t', '--type', type='string', dest='target', help='Type to case object to')

  return parser

def cast_to_type(debugger, command, result, internal_dict):
  #debugger.HandleCommand('pvc')

  command_args = shlex.split(command)
  parser = create_options_parser()

  try:
    (options, args) = parser.parse_args(command_args)

  except:
    result.setError("option parsing failed")

  var_name = options.var_name
  addr = options.address
  target = options.target

  new_command = string.Template("expr -l Swift -- let $var_name = unsafeBitCast($addr, to: $target.self)").substitute(**locals())
  print new_command
  debugger.HandleCommand(new_command)



def __lldb_init_module(debugger, internal_dict):
  debugger.HandleCommand('command script add -f test.cast_to_type cast_to_type')
  print 'The "cast_to_type" python command has been installed and is ready for use.'