Merge branch 'master' into E0403-update-error-format

Author: circuitfox

mk/crates.mk

@@ -60,7 +60,7 @@ RUSTC_CRATES := rustc rustc_typeck rustc_mir rustc_borrowck rustc_resolve rustc_
                 rustc_data_structures rustc_platform_intrinsics rustc_errors \
                 rustc_plugin rustc_metadata rustc_passes rustc_save_analysis \
                 rustc_const_eval rustc_const_math rustc_incremental
-HOST_CRATES := syntax syntax_ext syntax_pos $(RUSTC_CRATES) rustdoc fmt_macros \
+HOST_CRATES := syntax syntax_ext proc_macro syntax_pos $(RUSTC_CRATES) rustdoc fmt_macros \
 		flate arena graphviz rbml log serialize
 TOOLS := compiletest rustdoc rustc rustbook error_index_generator
 
@@ -100,6 +100,7 @@ DEPS_test := std getopts term native:rust_test_helpers
 
 DEPS_syntax := std term serialize log arena libc rustc_bitflags rustc_unicode rustc_errors syntax_pos
 DEPS_syntax_ext := syntax syntax_pos rustc_errors fmt_macros
+DEPS_proc_macro := syntax syntax_pos rustc_plugin log
 DEPS_syntax_pos := serialize
 
 DEPS_rustc_const_math := std syntax log serialize
@@ -114,8 +115,9 @@ DEPS_rustc_borrowck := rustc log graphviz syntax syntax_pos rustc_errors rustc_m
 DEPS_rustc_data_structures := std log serialize
 DEPS_rustc_driver := arena flate getopts graphviz libc rustc rustc_back rustc_borrowck \
                      rustc_typeck rustc_mir rustc_resolve log syntax serialize rustc_llvm \
-	             rustc_trans rustc_privacy rustc_lint rustc_plugin \
-                     rustc_metadata syntax_ext rustc_passes rustc_save_analysis rustc_const_eval \
+                     rustc_trans rustc_privacy rustc_lint rustc_plugin \
+                     rustc_metadata syntax_ext proc_macro \
+                     rustc_passes rustc_save_analysis rustc_const_eval \
                      rustc_incremental syntax_pos rustc_errors
 DEPS_rustc_errors := log libc serialize syntax_pos
 DEPS_rustc_lint := rustc log syntax syntax_pos rustc_const_eval

src/libcollections/vec.rs

@@ -1453,10 +1453,11 @@ impl<T> IntoIterator for Vec<T> {
             } else {
                 begin.offset(self.len() as isize) as *const T
             };
-            let buf = ptr::read(&self.buf);
+            let cap = self.buf.cap();
             mem::forget(self);
             IntoIter {
-                _buf: buf,
+                buf: Shared::new(begin),
+                cap: cap,
                 ptr: begin,
                 end: end,
             }
@@ -1708,8 +1709,9 @@ impl<'a, T> FromIterator<T> for Cow<'a, [T]> where T: Clone {
 /// [`IntoIterator`]: ../../std/iter/trait.IntoIterator.html
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct IntoIter<T> {
-    _buf: RawVec<T>,
-    ptr: *mut T,
+    buf: Shared<T>,
+    cap: usize,
+    ptr: *const T,
     end: *const T,
 }
 
@@ -1750,7 +1752,7 @@ impl<T> IntoIter<T> {
     #[unstable(feature = "vec_into_iter_as_slice", issue = "35601")]
     pub fn as_mut_slice(&self) -> &mut [T] {
         unsafe {
-            slice::from_raw_parts_mut(self.ptr, self.len())
+            slice::from_raw_parts_mut(self.ptr as *mut T, self.len())
         }
     }
 }
@@ -1846,9 +1848,10 @@ impl<T> Drop for IntoIter<T> {
     #[unsafe_destructor_blind_to_params]
     fn drop(&mut self) {
         // destroy the remaining elements
-        for _x in self {}
+        for _x in self.by_ref() {}
 
         // RawVec handles deallocation
+        let _ = unsafe { RawVec::from_raw_parts(*self.buf, self.cap) };
     }
 }
 

src/libcollectionstest/slice.rs

@@ -645,6 +645,24 @@ fn test_iter_size_hints() {
     assert_eq!(xs.iter_mut().size_hint(), (5, Some(5)));
 }
 
+#[test]
+fn test_iter_as_slice() {
+    let xs = [1, 2, 5, 10, 11];
+    let mut iter = xs.iter();
+    assert_eq!(iter.as_slice(), &[1, 2, 5, 10, 11]);
+    iter.next();
+    assert_eq!(iter.as_slice(), &[2, 5, 10, 11]);
+}
+
+#[test]
+fn test_iter_as_ref() {
+    let xs = [1, 2, 5, 10, 11];
+    let mut iter = xs.iter();
+    assert_eq!(iter.as_ref(), &[1, 2, 5, 10, 11]);
+    iter.next();
+    assert_eq!(iter.as_ref(), &[2, 5, 10, 11]);
+}
+
 #[test]
 fn test_iter_clone() {
     let xs = [1, 2, 5];

src/libcollectionstest/vec.rs

@@ -11,7 +11,7 @@
 use std::borrow::Cow;
 use std::iter::{FromIterator, repeat};
 use std::mem::size_of;
-use std::vec::Drain;
+use std::vec::{Drain, IntoIter};
 
 use test::Bencher;
 
@@ -537,6 +537,7 @@ fn test_cow_from() {
 #[allow(dead_code)]
 fn assert_covariance() {
     fn drain<'new>(d: Drain<'static, &'static str>) -> Drain<'new, &'new str> { d }
+    fn into_iter<'new>(i: IntoIter<&'static str>) -> IntoIter<&'new str> { i }
 }
 
 #[bench]

src/libcore/slice.rs

@@ -37,6 +37,7 @@ use clone::Clone;
 use cmp::{Ordering, PartialEq, PartialOrd, Eq, Ord};
 use cmp::Ordering::{Less, Equal, Greater};
 use cmp;
+use convert::AsRef;
 use default::Default;
 use fmt;
 use intrinsics::assume;
@@ -996,6 +997,13 @@ impl<'a, T> Clone for Iter<'a, T> {
     fn clone(&self) -> Iter<'a, T> { Iter { ptr: self.ptr, end: self.end, _marker: self._marker } }
 }
 
+#[stable(feature = "slice_iter_as_ref", since = "1.12.0")]
+impl<'a, T> AsRef<[T]> for Iter<'a, T> {
+    fn as_ref(&self) -> &[T] {
+        self.as_slice()
+    }
+}
+
 /// Mutable slice iterator.
 ///
 /// This struct is created by the [`iter_mut`] method on [slices].

src/libproc_macro/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+authors = ["The Rust Project Developers"]
+name = "proc_macro"
+version = "0.0.0"
+
+[lib]
+name = "proc_macro"
+path = "lib.rs"
+crate-type = ["dylib"]
+
+[dependencies]
+log = { path = "../liblog" }
+rustc_plugin = { path = "../librustc_plugin" }
+syntax = { path = "../libsyntax" }
+syntax_pos = { path = "../libsyntax_pos" }

src/libproc_macro/build.rs

@@ -0,0 +1,89 @@
+// 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())
+}

src/libproc_macro/lib.rs

@@ -0,0 +1,137 @@
+// 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.
+
+//! # Proc_Macro
+//!
+//! 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
+//! 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
+//! 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
+//! input. For example, `qquote!(5 + 5)` will produce a program, that, when run, will
+//! construct the TokenStream `5 | + | 5`.
+//!
+//! ### Unquoting
+//!
+//! Unquoting is currently done as `unquote`, and works by taking the single next
+//! TokenTree in the TokenStream as the unquoted term. Ergonomically, `unquote(foo)` works
+//! fine, but `unquote foo` is also supported.
+//!
+//! A simple example might be:
+//!
+//!```
+//!fn double(tmp: TokenStream) -> TokenStream {
+//!    qquote!(unquote(tmp) * 2)
+//!}
+//!```
+//!
+//! ### Large Example: Implementing Scheme's `cond`
+//!
+//! Below is the full implementation of Scheme's `cond` operator.
+//!
+//! ```
+//! fn cond_rec(input: TokenStream) -> TokenStream {
+//!   if input.is_empty() { return quote!(); }
+//!
+//!   let next = input.slice(0..1);
+//!   let rest = input.slice_from(1..);
+//!
+//!   let clause : TokenStream = match next.maybe_delimited() {
+//!     Some(ts) => ts,
+//!     _ => panic!("Invalid input"),
+//!   };
+//!
+//!   // clause is ([test]) [rhs]
+//!   if clause.len() < 2 { panic!("Invalid macro usage in cond: {:?}", clause) }
+//!
+//!   let test: TokenStream = clause.slice(0..1);
+//!   let rhs: TokenStream = clause.slice_from(1..);
+//!
+//!   if ident_eq(&test[0], str_to_ident("else")) || rest.is_empty() {
+//!     quote!({unquote(rhs)})
+//!   } else {
+//!     quote!({if unquote(test) { unquote(rhs) } else { cond!(unquote(rest)) } })
+//!   }
+//! }
+//! ```
+//!
+
+#![crate_name = "proc_macro"]
+#![unstable(feature = "rustc_private", issue = "27812")]
+#![feature(plugin_registrar)]
+#![crate_type = "dylib"]
+#![crate_type = "rlib"]
+#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
+       html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
+       html_root_url = "https://doc.rust-lang.org/nightly/")]
+#![cfg_attr(not(stage0), deny(warnings))]
+
+#![feature(staged_api)]
+#![feature(rustc_diagnostic_macros)]
+#![feature(rustc_private)]
+
+extern crate rustc_plugin;
+extern crate syntax;
+extern crate syntax_pos;
+#[macro_use] extern crate log;
+
+mod qquote;
+pub mod build;
+pub mod parse;
+pub mod prelude;
+use qquote::qquote;
+
+use rustc_plugin::Registry;
+
+// ____________________________________________________________________________________________
+// Main macro definition
+
+#[plugin_registrar]
+pub fn plugin_registrar(reg: &mut Registry) {
+    reg.register_macro("qquote", qquote);
+}