Stabilize std::path

This commit stabilizes essentially all of the new `std::path` API. The
API itself is changed in a couple of ways (which brings it in closer
alignment with the RFC):

* `.` components are now normalized away, unless they appear at the
  start of a path. This in turn effects the semantics of e.g. asking for
  the file name of `foo/` or `foo/.`, both of which yield `Some("foo")`
  now. This semantics is what the original RFC specified, and is also
  desirable given early experience rolling out the new API.

* The `parent` function now succeeds if, and only if, the path has at
  least one non-root/prefix component. This change affects `pop` as
  well.

* The `Prefix` component now involves a separate `PrefixComponent`
  struct, to better allow for keeping both parsed and unparsed prefix data.

In addition, the `old_path` module is now deprecated.

Closes #23264

[breaking-change]

src/compiletest/compiletest.rs

@@ -20,7 +20,6 @@
 #![feature(std_misc)]
 #![feature(test)]
 #![feature(core)]
-#![feature(path)]
 #![feature(io)]
 #![feature(net)]
 #![feature(path_ext)]

src/compiletest/procsrv.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![allow(deprecated)] // for old path, for dynamic_lib
+
 use std::process::{ExitStatus, Command, Child, Output, Stdio};
 use std::io::prelude::*;
 use std::dynamic_lib::DynamicLibrary;

src/librustc/lib.rs

@@ -40,7 +40,6 @@
 #![feature(unsafe_destructor)]
 #![feature(staged_api)]
 #![feature(std_misc)]
-#![feature(path)]
 #![feature(io)]
 #![feature(path_ext)]
 #![feature(str_words)]

src/librustc/plugin/load.rs

@@ -18,7 +18,10 @@ use std::borrow::ToOwned;
 use std::dynamic_lib::DynamicLibrary;
 use std::env;
 use std::mem;
+
+#[allow(deprecated)]
 use std::old_path;
+
 use std::path::PathBuf;
 use syntax::ast;
 use syntax::codemap::{Span, COMMAND_LINE_SP};
@@ -100,6 +103,7 @@ impl<'a> PluginLoader<'a> {
     }
 
     // Dynamically link a registrar function into the compiler process.
+    #[allow(deprecated)] // until #23197
     fn dylink_registrar(&mut self,
                         span: Span,
                         path: PathBuf,

src/librustc_back/fs.rs

@@ -11,6 +11,7 @@
 use std::io;
 use std::old_io::fs;
 use std::old_io;
+#[allow(deprecated)]
 use std::old_path;
 use std::os;
 use std::path::{Path, PathBuf};

src/librustc_back/lib.rs

@@ -42,11 +42,12 @@
 #![feature(old_io)]
 #![feature(old_path)]
 #![feature(os)]
-#![feature(path)]
 #![feature(rustc_private)]
 #![feature(staged_api)]
 #![feature(rand)]
 #![feature(path_ext)]
+#![feature(std_misc)]
+#![feature(path_relative_from)]
 
 extern crate syntax;
 extern crate serialize;

src/librustc_driver/lib.rs

@@ -37,7 +37,6 @@
 #![feature(unsafe_destructor)]
 #![feature(staged_api)]
 #![feature(exit_status)]
-#![feature(path)]
 #![feature(io)]
 
 extern crate arena;

src/librustc_llvm/lib.rs

@@ -31,7 +31,6 @@
 #![feature(libc)]
 #![feature(link_args)]
 #![feature(staged_api)]
-#![feature(path)]
 #![cfg_attr(unix, feature(std_misc))]
 
 extern crate libc;

src/librustc_trans/lib.rs

@@ -39,10 +39,10 @@
 #![feature(staged_api)]
 #![feature(unicode)]
 #![feature(io)]
-#![feature(path)]
 #![feature(path_ext)]
 #![feature(fs)]
 #![feature(hash)]
+#![feature(path_relative_from)]
 
 extern crate arena;
 extern crate flate;

src/librustdoc/lib.rs

@@ -37,9 +37,9 @@
 #![feature(unicode)]
 #![feature(str_words)]
 #![feature(io)]
-#![feature(path)]
 #![feature(file_path)]
 #![feature(path_ext)]
+#![feature(path_relative_from)]
 
 extern crate arena;
 extern crate getopts;
@@ -362,6 +362,7 @@ fn parse_externs(matches: &getopts::Matches) -> Result<core::Externs, String> {
 /// generated from the cleaned AST of the crate.
 ///
 /// This form of input will run all of the plug/cleaning passes
+#[allow(deprecated)] // for old Path in plugin manager
 fn rust_input(cratefile: &str, externs: core::Externs, matches: &getopts::Matches) -> Output {
     let mut default_passes = !matches.opt_present("no-defaults");
     let mut passes = matches.opt_strs("passes");

src/librustdoc/plugins.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![allow(deprecated)] // old path, used for compatibility with dynamic lib
+
 use clean;
 
 use std::dynamic_lib as dl;

src/libserialize/lib.rs

@@ -37,7 +37,6 @@ Core encoding and decoding interfaces.
 #![feature(staged_api)]
 #![feature(std_misc)]
 #![feature(unicode)]
-#![feature(path)]
 #![cfg_attr(test, feature(test))]
 
 // test harness access

src/libserialize/serialize.rs

@@ -14,6 +14,7 @@
 Core encoding and decoding interfaces.
 */
 
+#[allow(deprecated)]
 use std::old_path;
 use std::path;
 use std::rc::Rc;
@@ -539,12 +540,14 @@ macro_rules! tuple {
 
 tuple! { T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, }
 
+#[allow(deprecated)]
 impl Encodable for old_path::posix::Path {
     fn encode<S: Encoder>(&self, e: &mut S) -> Result<(), S::Error> {
         self.as_vec().encode(e)
     }
 }
 
+#[allow(deprecated)]
 impl Decodable for old_path::posix::Path {
     fn decode<D: Decoder>(d: &mut D) -> Result<old_path::posix::Path, D::Error> {
         let bytes: Vec<u8> = try!(Decodable::decode(d));
@@ -552,12 +555,14 @@ impl Decodable for old_path::posix::Path {
     }
 }
 
+#[allow(deprecated)]
 impl Encodable for old_path::windows::Path {
     fn encode<S: Encoder>(&self, e: &mut S) -> Result<(), S::Error> {
         self.as_vec().encode(e)
     }
 }
 
+#[allow(deprecated)]
 impl Decodable for old_path::windows::Path {
     fn decode<D: Decoder>(d: &mut D) -> Result<old_path::windows::Path, D::Error> {
         let bytes: Vec<u8> = try!(Decodable::decode(d));

src/libstd/dynamic_lib.rs

@@ -14,6 +14,7 @@
 
 #![unstable(feature = "std_misc")]
 #![allow(missing_docs)]
+#![allow(deprecated)] // will be addressed by #23197
 
 use prelude::v1::*;
 

src/libstd/env.rs

@@ -18,6 +18,7 @@
 
 use prelude::v1::*;
 
+use iter::IntoIterator;
 use error::Error;
 use ffi::{OsString, AsOsStr};
 use fmt;
@@ -338,9 +339,9 @@ pub struct JoinPathsError {
 /// ```
 #[stable(feature = "env", since = "1.0.0")]
 pub fn join_paths<I, T>(paths: I) -> Result<OsString, JoinPathsError>
-    where I: Iterator<Item=T>, T: AsOsStr
+    where I: IntoIterator<Item=T>, T: AsOsStr
 {
-    os_imp::join_paths(paths).map_err(|e| {
+    os_imp::join_paths(paths.into_iter()).map_err(|e| {
         JoinPathsError { inner: e }
     })
 }

src/libstd/ffi/os_str.rs

@@ -346,6 +346,7 @@ impl AsOsStr for String {
     }
 }
 
+#[allow(deprecated)]
 impl AsOsStr for Path {
     #[cfg(unix)]
     fn as_os_str(&self) -> &OsStr {

src/libstd/fs/mod.rs

@@ -571,19 +571,9 @@ pub fn create_dir<P: AsPath + ?Sized>(path: &P) -> io::Result<()> {
 pub fn create_dir_all<P: AsPath + ?Sized>(path: &P) -> io::Result<()> {
     let path = path.as_path();
     if path.is_dir() { return Ok(()) }
-    match path.parent() {
+    if let Some(p) = path.parent() { try!(create_dir_all(p)) }
-        Some(p) if p != path => try!(create_dir_all(p)),
-        _ => {}
-    }
-    // If the file name of the given `path` is blank then the creation of the
-    // parent directory will have taken care of the whole path for us, so we're
-    // good to go.
-    if path.file_name().is_none() {
-        Ok(())
-    } else {
     create_dir(path)
 }
-}
 
 /// Remove an existing, empty directory
 ///

src/libstd/old_path/mod.rs

@@ -60,6 +60,7 @@
 //! ```
 
 #![unstable(feature = "old_path")]
+#![deprecated(since = "1.0.0", reason = "use std::path instead")]
 #![allow(deprecated)] // seriously this is all deprecated
 #![allow(unused_imports)]
 

src/libstd/os.rs

@@ -29,6 +29,7 @@
 #![allow(missing_docs)]
 #![allow(non_snake_case)]
 #![allow(unused_imports)]
+#![allow(deprecated)]
 
 use self::MemoryMapKind::*;
 use self::MapOption::*;

src/libstd/sys/common/mod.rs

@@ -16,7 +16,10 @@ use prelude::v1::*;
 use sys::{last_error, retry};
 use ffi::CString;
 use num::Int;
+
+#[allow(deprecated)]
 use old_path::BytesContainer;
+
 use collections;
 
 pub mod backtrace;
@@ -120,6 +123,7 @@ pub trait FromInner<Inner> {
 }
 
 #[doc(hidden)]
+#[allow(deprecated)]
 pub trait ProcessConfig<K: BytesContainer, V: BytesContainer> {
     fn program(&self) -> &CString;
     fn args(&self) -> &[CString];

src/libstd/sys/unix/fs.rs

@@ -10,6 +10,8 @@
 
 //! Blocking posix-based file I/O
 
+#![allow(deprecated)] // this module itself is essentially deprecated
+
 use prelude::v1::*;
 
 use ffi::{CString, CStr};

src/libstd/sys/unix/process.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![allow(deprecated)]
+#![allow(deprecated)] // this module itself is essentially deprecated
 
 use prelude::v1::*;
 use self::Req::*;

src/libstd/sys/windows/backtrace.rs

@@ -23,6 +23,7 @@
 //! this takes the route of using StackWalk64 in order to walk the stack.
 
 #![allow(dead_code)]
+#![allow(deprecated)] // for old path for dynamic lib
 
 use dynamic_lib::DynamicLibrary;
 use ffi::CStr;

src/libstd/sys/windows/ext.rs

@@ -122,7 +122,7 @@ impl AsRawSocket for net::UdpSocket {
     fn as_raw_socket(&self) -> Socket { *self.as_inner().socket().as_inner() }
 }
 
-// Windows-specific extensions to `OsString`.
+/// Windows-specific extensions to `OsString`.
 pub trait OsStringExt {
     /// Create an `OsString` from a potentially ill-formed UTF-16 slice of 16-bit code units.
     ///
@@ -137,8 +137,12 @@ impl OsStringExt for OsString {
     }
 }
 
-// Windows-specific extensions to `OsStr`.
+/// Windows-specific extensions to `OsStr`.
 pub trait OsStrExt {
+    /// Re-encode an `OsStr` as a wide character sequence,
+    /// i.e. potentially ill-formed UTF-16.
+    ///
+    /// This is lossless. Note that the encoding does not include a final null.
     fn encode_wide(&self) -> EncodeWide;
 }
 

src/libstd/sys/windows/fs.rs

@@ -10,6 +10,8 @@
 
 //! Blocking Windows-based file I/O
 
+#![allow(deprecated)] // this module itself is essentially deprecated
+
 use libc::{self, c_int};
 
 use mem;

src/libstd/sys/windows/process.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![allow(deprecated)]
+#![allow(deprecated)] // this module itself is essentially deprecated
 
 use prelude::v1::*;
 

src/libsyntax/ext/source_util.rs

@@ -195,11 +195,7 @@ fn res_rel_file(cx: &mut ExtCtxt, sp: codemap::Span, arg: &Path) -> PathBuf {
     // NB: relative paths are resolved relative to the compilation unit
     if !arg.is_absolute() {
         let mut cu = PathBuf::new(&cx.codemap().span_to_filename(sp));
-        if cu.parent().is_some() {
         cu.pop();
-        } else {
-            cu = PathBuf::new("");
-        }
         cu.push(arg);
         cu
     } else {

src/libsyntax/lib.rs

@@ -38,7 +38,6 @@
 #![feature(staged_api)]
 #![feature(std_misc)]
 #![feature(unicode)]
-#![feature(path)]
 #![feature(io)]
 #![feature(path_ext)]
 

src/libsyntax/parse/parser.rs

@@ -5254,13 +5254,7 @@ impl<'a> Parser<'a> {
                     -> (ast::Item_, Vec<ast::Attribute> ) {
         let mut prefix = PathBuf::new(&self.sess.span_diagnostic.cm
                                            .span_to_filename(self.span));
-        // FIXME(acrichto): right now "a".pop() == "a", but need to confirm with
-        //                  aturon whether this is expected or not.
-        if prefix.parent().is_some() {
         prefix.pop();
-        } else {
-            prefix = PathBuf::new("");
-        }
         let mut dir_path = prefix;
         for part in &self.mod_path_stack {
             dir_path.push(&**part);

src/libsyntax/parse/token.rs

@@ -25,6 +25,7 @@ use serialize::{Decodable, Decoder, Encodable, Encoder};
 use std::fmt;
 use std::mem;
 use std::ops::Deref;
+#[allow(deprecated)]
 use std::old_path::BytesContainer;
 use std::rc::Rc;
 
@@ -638,6 +639,7 @@ impl Deref for InternedString {
     fn deref(&self) -> &str { &*self.string }
 }
 
+#[allow(deprecated)]
 impl BytesContainer for InternedString {
     fn container_as_bytes<'a>(&'a self) -> &'a [u8] {
         // FIXME #12938: This is a workaround for the incorrect signature

src/libterm/lib.rs

@@ -57,7 +57,6 @@
 #![feature(int_uint)]
 #![feature(io)]
 #![feature(old_io)]
-#![feature(path)]
 #![feature(rustc_private)]
 #![feature(staged_api)]
 #![feature(std_misc)]

src/libtest/lib.rs

@@ -40,7 +40,6 @@
 #![feature(core)]
 #![feature(int_uint)]
 #![feature(old_io)]
-#![feature(path)]
 #![feature(rustc_private)]
 #![feature(staged_api)]
 #![feature(std_misc)]

src/rustbook/main.rs

@@ -14,7 +14,6 @@
 #![feature(exit_status)]
 #![feature(io)]
 #![feature(old_io)]
-#![feature(path)]
 #![feature(rustdoc)]
 #![feature(rustc_private)]