| // Copyright 2013-2015 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, quote, rustc_private)] |
| |
| extern crate syntax; |
| extern crate rustc; |
| extern crate rustc_plugin; |
| |
| use syntax::ast::{self, TokenTree, Item, MetaItem, ImplItem, TraitItem}; |
| use syntax::codemap::Span; |
| use syntax::ext::base::*; |
| use syntax::parse::{self, token}; |
| use syntax::ptr::P; |
| use rustc_plugin::Registry; |
| |
| #[macro_export] |
| macro_rules! exported_macro { () => (2) } |
| macro_rules! unexported_macro { () => (3) } |
| |
| #[plugin_registrar] |
| pub fn plugin_registrar(reg: &mut Registry) { |
| reg.register_macro("make_a_1", expand_make_a_1); |
| reg.register_macro("identity", expand_identity); |
| reg.register_syntax_extension( |
| token::intern("into_multi_foo"), |
| // FIXME (#22405): Replace `Box::new` with `box` here when/if possible. |
| MultiModifier(Box::new(expand_into_foo_multi))); |
| reg.register_syntax_extension( |
| token::intern("duplicate"), |
| // FIXME (#22405): Replace `Box::new` with `box` here when/if possible. |
| MultiDecorator(Box::new(expand_duplicate))); |
| } |
| |
| fn expand_make_a_1(cx: &mut ExtCtxt, sp: Span, tts: &[TokenTree]) |
| -> Box<MacResult+'static> { |
| if !tts.is_empty() { |
| cx.span_fatal(sp, "make_a_1 takes no arguments"); |
| } |
| MacEager::expr(quote_expr!(cx, 1)) |
| } |
| |
| // See Issue #15750 |
| fn expand_identity(cx: &mut ExtCtxt, _span: Span, tts: &[TokenTree]) |
| -> Box<MacResult+'static> { |
| // Parse an expression and emit it unchanged. |
| let mut parser = parse::new_parser_from_tts(cx.parse_sess(), |
| cx.cfg(), tts.to_vec()); |
| let expr = parser.parse_expr().unwrap(); |
| MacEager::expr(quote_expr!(&mut *cx, $expr)) |
| } |
| |
| fn expand_into_foo_multi(cx: &mut ExtCtxt, |
| sp: Span, |
| attr: &MetaItem, |
| it: Annotatable) -> Annotatable { |
| match it { |
| Annotatable::Item(it) => { |
| Annotatable::Item(P(Item { |
| attrs: it.attrs.clone(), |
| ..(*quote_item!(cx, enum Foo2 { Bar2, Baz2 }).unwrap()).clone() |
| })) |
| } |
| Annotatable::ImplItem(it) => { |
| quote_item!(cx, impl X { fn foo(&self) -> i32 { 42 } }).unwrap().and_then(|i| { |
| match i.node { |
| ast::ItemImpl(_, _, _, _, _, mut items) => { |
| Annotatable::ImplItem(items.pop().expect("impl method not found")) |
| } |
| _ => unreachable!("impl parsed to something other than impl") |
| } |
| }) |
| } |
| Annotatable::TraitItem(it) => { |
| quote_item!(cx, trait X { fn foo(&self) -> i32 { 0 } }).unwrap().and_then(|i| { |
| match i.node { |
| ast::ItemTrait(_, _, _, mut items) => { |
| Annotatable::TraitItem(items.pop().expect("trait method not found")) |
| } |
| _ => unreachable!("trait parsed to something other than trait") |
| } |
| }) |
| } |
| } |
| } |
| |
| // Create a duplicate of the annotatable, based on the MetaItem |
| fn expand_duplicate(cx: &mut ExtCtxt, |
| sp: Span, |
| mi: &MetaItem, |
| it: &Annotatable, |
| push: &mut FnMut(Annotatable)) |
| { |
| let copy_name = match mi.node { |
| ast::MetaItem_::MetaList(_, ref xs) => { |
| if let ast::MetaItem_::MetaWord(ref w) = xs[0].node { |
| token::str_to_ident(&w) |
| } else { |
| cx.span_err(mi.span, "Expected word"); |
| return; |
| } |
| } |
| _ => { |
| cx.span_err(mi.span, "Expected list"); |
| return; |
| } |
| }; |
| |
| // Duplicate the item but replace its ident by the MetaItem |
| match it.clone() { |
| Annotatable::Item(it) => { |
| let mut new_it = (*it).clone(); |
| new_it.attrs.clear(); |
| new_it.ident = copy_name; |
| push(Annotatable::Item(P(new_it))); |
| } |
| Annotatable::ImplItem(it) => { |
| let mut new_it = (*it).clone(); |
| new_it.attrs.clear(); |
| new_it.ident = copy_name; |
| push(Annotatable::ImplItem(P(new_it))); |
| } |
| Annotatable::TraitItem(tt) => { |
| let mut new_it = (*tt).clone(); |
| new_it.attrs.clear(); |
| new_it.ident = copy_name; |
| push(Annotatable::TraitItem(P(new_it))); |
| } |
| } |
| } |
| |
| pub fn foo() {} |