New upstream version 1.28.0~beta.14+dfsg1

[rustc.git] / src / test / run-pass-fulldeps / auxiliary / plugin_args.rs

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// force-host

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

extern crate syntax;
extern crate syntax_pos;
extern crate rustc;
extern crate rustc_plugin;

use std::borrow::ToOwned;
use syntax::ast;
use syntax::ext::hygiene;
use syntax::ext::build::AstBuilder;
use syntax::ext::base::{TTMacroExpander, ExtCtxt, MacResult, MacEager, NormalTT};
use syntax::print::pprust;
use syntax::ptr::P;
use syntax::symbol::Symbol;
use syntax_pos::Span;
use syntax::tokenstream::TokenStream;
use rustc_plugin::Registry;

struct Expander {
    args: Vec<ast::NestedMetaItem>,
}

impl TTMacroExpander for Expander {
    fn expand<'cx>(&self,
                   ecx: &'cx mut ExtCtxt,
                   sp: Span,
                   _: TokenStream) -> Box<MacResult+'cx> {
        let args = self.args.iter().map(|i| pprust::meta_list_item_to_string(i))
            .collect::<Vec<_>>().join(", ");
        MacEager::expr(ecx.expr_str(sp, Symbol::intern(&args)))
    }
}

#[plugin_registrar]
pub fn plugin_registrar(reg: &mut Registry) {
    let args = reg.args().to_owned();
    reg.register_syntax_extension(Symbol::intern("plugin_args"),
        NormalTT {
            expander: Box::new(Expander { args: args, }),
            def_info: None,
            allow_internal_unstable: false,
            allow_internal_unsafe: false,
            unstable_feature: None,
            edition: hygiene::default_edition(),
        });
}