pydev_modify_bytecode.py 文件源码

def _unpack_opargs(code, inserted_code_list, current_index):
    """
    Modified version of `_unpack_opargs` function from module `dis`.
    We have to use it, because sometimes code can be in an inconsistent state: if EXTENDED_ARG
    operator was introduced into the code, but it hasn't been inserted into `code_list` yet.
    In this case we can't use standard `_unpack_opargs` and we should check whether there are
    some new operators in `inserted_code_list`.
    """
    extended_arg = 0
    for i in range(0, len(code), 2):
        op = code[i]
        if op >= HAVE_ARGUMENT:
            if not extended_arg:
                # in case if we added EXTENDED_ARG, but haven't inserted it to the source code yet.
                for code_index in range(current_index, len(inserted_code_list)):
                    inserted_offset, inserted_code = inserted_code_list[code_index]
                    if inserted_offset == i and inserted_code[0] == EXTENDED_ARG:
                        extended_arg = inserted_code[1] << 8
            arg = code[i+1] | extended_arg
            extended_arg = (arg << 8) if op == EXTENDED_ARG else 0
        else:
            arg = None
        yield (i, op, arg)