proc_macro: move compiler crate imports to the rustc module.

Author: eddyb

src/libproc_macro/lib.rs

@@ -42,11 +42,6 @@
 #![feature(box_into_raw_non_null)]
 #![feature(nonnull_cast)]
 
-extern crate syntax;
-extern crate syntax_pos;
-extern crate rustc_errors;
-extern crate rustc_data_structures;
-
 #[unstable(feature = "proc_macro_internals", issue = "27812")]
 #[doc(hidden)]
 pub mod bridge;
@@ -66,8 +61,6 @@ use std::{ascii, fmt, iter};
 use std::path::PathBuf;
 use std::str::FromStr;
 
-use syntax::symbol::Symbol;
-
 /// The main type provided by this crate, representing an abstract stream of
 /// tokens.
 ///
@@ -400,13 +393,13 @@ pub enum Delimiter {
 /// An interned string.
 #[derive(Copy, Clone, Debug)]
 #[unstable(feature = "proc_macro", issue = "38356")]
-pub struct Term(Symbol);
+pub struct Term(::rustc::Symbol);
 
 impl Term {
     /// Intern a string into a `Term`.
     #[unstable(feature = "proc_macro", issue = "38356")]
     pub fn intern(string: &str) -> Term {
-        Term(Symbol::intern(string))
+        Term(::rustc::Symbol::intern(string))
     }
 
     /// Get a reference to the interned string.

src/libproc_macro/rustc.rs

@@ -8,17 +8,24 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+extern crate syntax;
+extern crate syntax_pos;
+extern crate rustc_errors;
+extern crate rustc_data_structures;
+
 use {Delimiter, Literal, LiteralKind, Spacing, Term, TokenNode};
 
-use rustc_data_structures::sync::Lrc;
-use rustc_errors::{Diagnostic, DiagnosticBuilder, Level};
 use std::path::PathBuf;
-use syntax_pos::{self, SyntaxContext, FileMap, FileName, MultiSpan, Pos, DUMMY_SP};
-use syntax_pos::hygiene::Mark;
-use syntax::ast;
-use syntax::ext::base::{ExtCtxt, ProcMacro};
-use syntax::parse::{self, token, ParseSess};
-use syntax::tokenstream;
+use self::rustc_data_structures::sync::Lrc;
+use self::rustc_errors::{Diagnostic, DiagnosticBuilder, Level};
+use self::syntax_pos::{SyntaxContext, FileMap, FileName, MultiSpan, Pos, DUMMY_SP};
+use self::syntax_pos::hygiene::Mark;
+use self::syntax::ast;
+use self::syntax::ext::base::{ExtCtxt, ProcMacro};
+use self::syntax::parse::{self, token, ParseSess};
+use self::syntax::tokenstream;
+
+pub use self::syntax_pos::symbol::Symbol;
 
 pub struct Quoter;
 
@@ -169,8 +176,8 @@ impl<'a> ::bridge::FrontendInterface for Rustc<'a> {
     }
     fn token_stream_from_token_tree(&self, node: ::TokenNode, span: Self::Span)
                                     -> Self::TokenStream {
-        use syntax::parse::token::*;
-        use syntax::tokenstream::TokenTree;
+        use self::syntax::parse::token::*;
+        use self::syntax::tokenstream::TokenTree;
 
         let (op, kind) = match node {
             TokenNode::Op(op, kind) => (op, kind),
@@ -224,7 +231,7 @@ impl<'a> ::bridge::FrontendInterface for Rustc<'a> {
                                   -> (Self::Span,
                                       Result<(::TokenNode, Option<Self::TokenStream>),
                                              (::Delimiter, Self::TokenStream)>) {
-        use syntax::parse::token::*;
+        use self::syntax::parse::token::*;
 
         let mut next = None;