Split up libproc_macro_plugin

Separate the plugin code from non-plugin code to break a potential cycle in crates.

This will allow us to merge the new libproc_macro_tokens into libproc_macro.

6 files changed, 13 insertions, 175 deletions

diff --git a/src/libproc_macro_plugin/Cargo.toml b/src/libproc_macro_plugin/Cargo.toml
index 70bb86d0f58..4bc3f488d32 100644
--- a/src/libproc_macro_plugin/Cargo.toml
+++ b/src/libproc_macro_plugin/Cargo.toml
@@ -12,3 +12,4 @@ log = { path = "../liblog" }
 rustc_plugin = { path = "../librustc_plugin" }
 syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
+proc_macro_tokens = { path = "../libproc_macro_tokens" }
diff --git a/src/libproc_macro_plugin/build.rs b/src/libproc_macro_plugin/build.rs
deleted file mode 100644
index 7b7590b863b..00000000000
--- a/src/libproc_macro_plugin/build.rs
+++ /dev/null
@@ -1,89 +0,0 @@
-// Copyright 2016 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.
-
-extern crate syntax;
-extern crate syntax_pos;
-
-use syntax::ast::Ident;
-use syntax::codemap::DUMMY_SP;
-use syntax::parse::token::{self, Token, keywords, str_to_ident};
-use syntax::tokenstream::{self, TokenTree, TokenStream};
-use std::rc::Rc;
-
-/// A wrapper around `TokenStream::concat` to avoid extra namespace specification and
-/// provide TokenStream concatenation as a generic operator.
-pub fn concat(ts1: TokenStream, ts2: TokenStream) -> TokenStream {
-    TokenStream::concat(ts1, ts2)
-}
-
-/// Checks if two identifiers have the same name, disregarding context. This allows us to
-/// fake 'reserved' keywords.
-// FIXME We really want `free-identifier-=?` (a la Dybvig 1993). von Tander 2007 is
-// probably the easiest way to do that.
-pub fn ident_eq(tident: &TokenTree, id: Ident) -> bool {
-    let tid = match *tident {
-        TokenTree::Token(_, Token::Ident(ref id)) => id,
-        _ => {
-            return false;
-        }
-    };
-
-    tid.name == id.name
-}
-
-// ____________________________________________________________________________________________
-// Conversion operators
-
-/// Convert a `&str` into a Token.
-pub fn str_to_token_ident(s: &str) -> Token {
-    Token::Ident(str_to_ident(s))
-}
-
-/// Converts a keyword (from `syntax::parse::token::keywords`) into a Token that
-/// corresponds to it.
-pub fn keyword_to_token_ident(kw: keywords::Keyword) -> Token {
-    Token::Ident(str_to_ident(&kw.name().as_str()[..]))
-}
-
-// ____________________________________________________________________________________________
-// Build Procedures
-
-/// Generically takes a `ts` and delimiter and returns `ts` delimited by the specified
-/// delimiter.
-pub fn build_delimited(ts: TokenStream, delim: token::DelimToken) -> TokenStream {
-    let tts = ts.to_tts();
-    TokenStream::from_tts(vec![TokenTree::Delimited(DUMMY_SP,
-                                                    Rc::new(tokenstream::Delimited {
-                                                        delim: delim,
-                                                        open_span: DUMMY_SP,
-                                                        tts: tts,
-                                                        close_span: DUMMY_SP,
-                                                    }))])
-}
-
-/// Takes `ts` and returns `[ts]`.
-pub fn build_bracket_delimited(ts: TokenStream) -> TokenStream {
-    build_delimited(ts, token::DelimToken::Bracket)
-}
-
-/// Takes `ts` and returns `{ts}`.
-pub fn build_brace_delimited(ts: TokenStream) -> TokenStream {
-    build_delimited(ts, token::DelimToken::Brace)
-}
-
-/// Takes `ts` and returns `(ts)`.
-pub fn build_paren_delimited(ts: TokenStream) -> TokenStream {
-    build_delimited(ts, token::DelimToken::Paren)
-}
-
-/// Constructs `()`.
-pub fn build_empty_args() -> TokenStream {
-    build_paren_delimited(TokenStream::mk_empty())
-}
diff --git a/src/libproc_macro_plugin/lib.rs b/src/libproc_macro_plugin/lib.rs
index e82e97b5134..c45762bfb6e 100644
--- a/src/libproc_macro_plugin/lib.rs
+++ b/src/libproc_macro_plugin/lib.rs
@@ -13,43 +13,14 @@
 //! A library for procedural macro writers.
 //!
 //! ## Usage
-//! This package provides the `qquote!` macro for syntax creation, and the prelude
-//! (at libproc_macro::prelude) provides a number of operations:
-//! - `concat`, for concatenating two TokenStreams.
-//! - `ident_eq`, for checking if two identifiers are equal regardless of syntax context.
-//! - `str_to_token_ident`, for converting an `&str` into a Token.
-//! - `keyword_to_token_delim`, for converting a `parse::token::keywords::Keyword` into a
-//!    Token.
-//! - `build_delimited`, for creating a new TokenStream from an existing one and a delimiter
-//!    by wrapping the TokenStream in the delimiter.
-//! - `build_bracket_delimited`, `build_brace_delimited`, and `build_paren_delimited`, for
-//!    easing the above.
-//! - `build_empty_args`, which returns a TokenStream containing `()`.
-//! - `lex`, which takes an `&str` and returns the TokenStream it represents.
-//!
-//! The `qquote!` macro also imports `syntax::ext::proc_macro_shim::prelude::*`, so you
+//! This crate provides the `qquote!` macro for syntax creation.
+//!
+//! The `qquote!` macro imports `syntax::ext::proc_macro_shim::prelude::*`, so you
 //! will need to `extern crate syntax` for usage. (This is a temporary solution until more
-//! of the external API in libproc_macro is stabilized to support the token construction
+//! of the external API in libproc_macro_tokens is stabilized to support the token construction
 //! operations that the qausiquoter relies on.) The shim file also provides additional
 //! operations, such as `build_block_emitter` (as used in the `cond` example below).
 //!
-//! ## TokenStreams
-//!
-//! TokenStreams serve as the basis of the macro system. They are, in essence, vectors of
-//! TokenTrees, where indexing treats delimited values as a single term. That is, the term
-//! `even(a+c) && even(b)` will be indexibly encoded as `even | (a+c) | even | (b)` where,
-//! in reality, `(a+c)` is actually a decorated pointer to `a | + | c`.
-//!
-//! If a user has a TokenStream that is a single, delimited value, they can use
-//! `maybe_delimited` to destruct it and receive the internal vector as a new TokenStream
-//! as:
-//! ```
-//! `(a+c)`.maybe_delimited() ~> Some(a | + | c)`
-//! ```
-//!
-//! Check the TokenStream documentation for more information; the structure also provides
-//! cheap concatenation and slicing.
-//!
 //! ## Quasiquotation
 //!
 //! The quasiquoter creates output that, when run, constructs the tokenstream specified as
@@ -118,12 +89,11 @@
 extern crate rustc_plugin;
 extern crate syntax;
 extern crate syntax_pos;
+extern crate proc_macro_tokens;
 #[macro_use] extern crate log;
 
 mod qquote;
-pub mod build;
-pub mod parse;
-pub mod prelude;
+
 use qquote::qquote;
 
 use rustc_plugin::Registry;
diff --git a/src/libproc_macro_plugin/parse.rs b/src/libproc_macro_plugin/parse.rs
deleted file mode 100644
index 9af8a68cdcf..00000000000
--- a/src/libproc_macro_plugin/parse.rs
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2016 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.
-
-//! Parsing utilities for writing procedural macros.
-
-extern crate syntax;
-
-use syntax::parse::{ParseSess, filemap_to_tts};
-use syntax::tokenstream::TokenStream;
-
-/// Map a string to tts, using a made-up filename. For example, `lex(15)` will return a
-/// TokenStream containing the literal 15.
-pub fn lex(source_str: &str) -> TokenStream {
-    let ps = ParseSess::new();
-    TokenStream::from_tts(filemap_to_tts(&ps,
-                                         ps.codemap().new_filemap("procmacro_lex".to_string(),
-                                                                  None,
-                                                                  source_str.to_owned())))
-}
diff --git a/src/libproc_macro_plugin/prelude.rs b/src/libproc_macro_plugin/prelude.rs
deleted file mode 100644
index 4c0c8ba6c66..00000000000
--- a/src/libproc_macro_plugin/prelude.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2016 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.
-
-pub use build::*;
-pub use parse::*;
diff --git a/src/libproc_macro_plugin/qquote.rs b/src/libproc_macro_plugin/qquote.rs
index b73d085656e..e5a3abc2ea9 100644
--- a/src/libproc_macro_plugin/qquote.rs
+++ b/src/libproc_macro_plugin/qquote.rs
@@ -24,12 +24,9 @@
 //! TokenStream that resembles the output syntax.
 //!
 
-extern crate rustc_plugin;
-extern crate syntax;
-extern crate syntax_pos;
+use proc_macro_tokens::build::*;
+use proc_macro_tokens::parse::lex;
 
-use build::*;
-use parse::lex;
 use qquote::int_build::*;
 
 use syntax::ast::Ident;
@@ -51,7 +48,7 @@ pub fn qquote<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[TokenTree])
     let output = qquoter(cx, TokenStream::from_tts(tts.clone().to_owned()));
     debug!("\nQQ out: {}\n", pprust::tts_to_string(&output.to_tts()[..]));
     let imports = concat(lex("use syntax::ext::proc_macro_shim::prelude::*;"),
-                         lex("use proc_macro_plugin::prelude::*;"));
+                         lex("use proc_macro_tokens::prelude::*;"));
     build_block_emitter(cx, sp, build_brace_delimited(concat(imports, output)))
 }
 
@@ -219,7 +216,7 @@ fn convert_complex_tts<'cx>(cx: &'cx mut ExtCtxt, tts: Vec<QTT>) -> (Bindings, T
 
                 let sep = build_delim_tok(qdl.delim);
 
-                pushes.push(build_mod_call(vec![str_to_ident("proc_macro_plugin"),
+                pushes.push(build_mod_call(vec![str_to_ident("proc_macro_tokens"),
                                                str_to_ident("build"),
                                                str_to_ident("build_delimited")],
                                           concat(from_tokens(vec![Token::Ident(new_id)]),
@@ -264,11 +261,8 @@ fn is_qquote(id: Ident) -> bool {
 }
 
 mod int_build {
-    extern crate syntax;
-    extern crate syntax_pos;
-
-    use parse::*;
-    use build::*;
+    use proc_macro_tokens::build::*;
+    use proc_macro_tokens::parse::*;
 
     use syntax::ast::{self, Ident};
     use syntax::codemap::{DUMMY_SP};