| // Copyright 2012 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. |
| |
| use ast; |
| use attr; |
| use std::cell::Cell; |
| use ext::hygiene::{Mark, SyntaxContext}; |
| use symbol::{Symbol, keywords}; |
| use syntax_pos::{DUMMY_SP, Span}; |
| use codemap::{ExpnInfo, NameAndSpan, MacroAttribute}; |
| use ptr::P; |
| use tokenstream::TokenStream; |
| |
| /// Craft a span that will be ignored by the stability lint's |
| /// call to codemap's `is_internal` check. |
| /// The expanded code uses the unstable `#[prelude_import]` attribute. |
| fn ignored_span(sp: Span) -> Span { |
| let mark = Mark::fresh(Mark::root()); |
| mark.set_expn_info(ExpnInfo { |
| call_site: DUMMY_SP, |
| callee: NameAndSpan { |
| format: MacroAttribute(Symbol::intern("std_inject")), |
| span: None, |
| allow_internal_unstable: true, |
| allow_internal_unsafe: false, |
| } |
| }); |
| sp.with_ctxt(SyntaxContext::empty().apply_mark(mark)) |
| } |
| |
| pub fn injected_crate_name() -> Option<&'static str> { |
| INJECTED_CRATE_NAME.with(|name| name.get()) |
| } |
| |
| thread_local! { |
| static INJECTED_CRATE_NAME: Cell<Option<&'static str>> = Cell::new(None); |
| } |
| |
| pub fn maybe_inject_crates_ref(mut krate: ast::Crate, alt_std_name: Option<String>) -> ast::Crate { |
| let name = if attr::contains_name(&krate.attrs, "no_core") { |
| return krate; |
| } else if attr::contains_name(&krate.attrs, "no_std") { |
| "core" |
| } else { |
| "std" |
| }; |
| |
| INJECTED_CRATE_NAME.with(|opt_name| opt_name.set(Some(name))); |
| |
| let crate_name = Symbol::intern(&alt_std_name.unwrap_or_else(|| name.to_string())); |
| |
| krate.module.items.insert(0, P(ast::Item { |
| attrs: vec![attr::mk_attr_outer(DUMMY_SP, |
| attr::mk_attr_id(), |
| attr::mk_word_item(Symbol::intern("macro_use")))], |
| vis: ast::Visibility::Inherited, |
| node: ast::ItemKind::ExternCrate(Some(crate_name)), |
| ident: ast::Ident::from_str(name), |
| id: ast::DUMMY_NODE_ID, |
| span: DUMMY_SP, |
| tokens: None, |
| })); |
| |
| let span = ignored_span(DUMMY_SP); |
| krate.module.items.insert(0, P(ast::Item { |
| attrs: vec![ast::Attribute { |
| style: ast::AttrStyle::Outer, |
| path: ast::Path::from_ident(span, ast::Ident::from_str("prelude_import")), |
| tokens: TokenStream::empty(), |
| id: attr::mk_attr_id(), |
| is_sugared_doc: false, |
| span, |
| }], |
| vis: ast::Visibility::Inherited, |
| node: ast::ItemKind::Use(P(ast::UseTree { |
| prefix: ast::Path { |
| segments: ["{{root}}", name, "prelude", "v1"].into_iter().map(|name| { |
| ast::PathSegment::from_ident(ast::Ident::from_str(name), DUMMY_SP) |
| }).collect(), |
| span, |
| }, |
| kind: ast::UseTreeKind::Glob, |
| span, |
| })), |
| id: ast::DUMMY_NODE_ID, |
| ident: keywords::Invalid.ident(), |
| span, |
| tokens: None, |
| })); |
| |
| krate |
| } |