test_walker.py 文件源码

def test_list_element():
    """
    Tests the removal of an AST node that is an element of a list
    referenced by a field of the parent node.
    """

    @ast_transformer
    def remove_list_element(node, **kwds):
        if isinstance(node, ast.Assign) and node.targets[0].id == 'a':
            return None
        else:
            return node

    node = get_ast(dummy)
    new_node = check_mutation(node, remove_list_element)
    assert_ast_equal(new_node, get_ast("""
        def dummy(x, y):
            c = 4
        """))