Broken reexport generation

Cargo.toml

[package]

name = "gen"
version = "0.0.1"
authors = ["Manish Goregaokar <manishsmail@gmail.com>"]


[lib]
name = "gen"
path = "lib.rs"
plugin = true

lib.rs

#![feature(plugin, box_syntax, plugin_registrar)]

#[plugin]
#[macro_use]
extern crate syntax;
#[plugin]
#[macro_use]
extern crate rustc;

use rustc::lint::LintPassObject;
use rustc::plugin::Registry;
use syntax::ext::base::{Decorator, Modifier};

use syntax::ext::base::ExtCtxt;
use syntax::codemap::Span;
use syntax::ptr::P;
use syntax::ast::{Item, MetaItem, Expr, Visibility};
use syntax::ast;
use syntax::attr;
use syntax::ext::build::AstBuilder;
use syntax::ext::deriving::generic::{combine_substructure, EnumMatching, FieldInfo, MethodDef, Struct, Substructure, TraitDef, ty};
use syntax::parse::token::{intern, InternedString};
use std::slice::SliceConcatExt;


#[plugin_registrar]
pub fn plugin_registrar(reg: &mut Registry) {
    reg.register_syntax_extension(intern("ree"), Decorator(box expand_ree));
}

pub fn expand_ree(cx: &mut ExtCtxt, span: Span, _: &MetaItem, _: &Item, mut push: Box<FnMut(P<Item>)>) {
    let mut generator = |buf: &[&str]| {
        let path = cx.path(span, buf.iter().map(|x| intern(*x).ident()).collect());
        push(cx.item_use_simple(span, Visibility::Public, path))
    };

    generator(&["dom", "bindings", "FooCast"]);
}

test.rs

#![feature(plugin, box_syntax, plugin_registrar)]

#[plugin]
extern crate gen;

fn main(){}

mod dom {
    
    mod attr {
        use dom::node::FooCast;
    }
    mod bindings {
        pub trait FooCast{}
    }
    mod node {
        #[ree]
        struct Node;
    }

}