modulegraph.py 文件源码

def alias_module(self, src_module_name, trg_module_name):
        """
        Alias the source module to the target module with the passed names.

        This method ensures that the next call to findNode() given the target
        module name will resolve this alias. This includes importing and adding
        a graph node for the source module if needed as well as adding a
        reference from the target to source module.

        Parameters
        ----------
        src_module_name : str
            Fully-qualified name of the existing **source module** (i.e., the
            module being aliased).
        trg_module_name : str
            Fully-qualified name of the non-existent **target module** (i.e.,
            the alias to be created).
        """
        self.msg(3, 'alias_module "%s" -> "%s"' % (src_module_name, trg_module_name))
        # print('alias_module "%s" -> "%s"' % (src_module_name, trg_module_name))
        assert isinstance(src_module_name, str), '"%s" not a module name.' % str(src_module_name)
        assert isinstance(trg_module_name, str), '"%s" not a module name.' % str(trg_module_name)

        # If the target module has already been added to the graph as either a
        # non-alias or as a different alias, raise an exception.
        trg_module = self.findNode(trg_module_name)
        if trg_module is not None and not (
           isinstance(trg_module, AliasNode) and
           trg_module.identifier == src_module_name):
            raise ValueError('Target module "%s" already imported as "%s".' % (trg_module_name, trg_module))

        # See findNode() for details.
        self.lazynodes[trg_module_name] = Alias(src_module_name)