module_rewriter.py 文件源码

def copy_function_with_closure(old_func, updated_module,
                               updated_wrapped_func):
  """Copies a function, updating it's globals to point to updated_module.
  This works for singly-wrapped function (ie, closure has len 1).
  """

  assert old_func.__closure__ and len(old_func.__closure__) == 1

  cell = make_cell()
  PyCell_Set = ctypes.pythonapi.PyCell_Set

  # ctypes.pythonapi functions need to have argtypes and restype set manually
  PyCell_Set.argtypes = (ctypes.py_object, ctypes.py_object)

  # restype actually defaults to c_int here, but we might as well be explicit
  PyCell_Set.restype = ctypes.c_int

  PyCell_Set(cell, updated_wrapped_func)

  new_closure = (cell,)
  new_func = types.FunctionType(old_func.__code__, updated_module.__dict__,
                                name=old_func.__name__,
                                argdefs=old_func.__defaults__,
                                closure=new_closure)
  new_func.__dict__.update(old_func.__dict__)
  new_func.__module__ = updated_module.__name__
  return new_func