std: Move std::env to the new I/O APIs

This commit moves `std::env` away from the `std::old_io` error type as well as
the `std::old_path` module. Methods returning an error now return `io::Error`
and methods consuming or returning paths use `std::path` instead of
`std::old_path`. This commit does not yet mark these APIs as `#[stable]`.

This commit also migrates `std::old_io::TempDir` to `std::fs::TempDir` with
essentially the exact same API. This type was added to interoperate with the new
path API and has its own `tempdir` feature.

Finally, this commit reverts the deprecation of `std::os` APIs returning the old
path API types. This deprecation can come back once the entire `std::old_path`
module is deprecated.

[breaking-change]

src/librustc/lib.rs

@@ -40,6 +40,7 @@
 #![feature(staged_api)]
 #![feature(std_misc)]
 #![feature(unicode)]
+#![feature(os)]
 #![cfg_attr(test, feature(test))]
 
 extern crate arena;

src/librustc/metadata/filesearch.rs

@@ -14,6 +14,7 @@ pub use self::FileMatch::*;
 
 use std::collections::HashSet;
 use std::env;
+use std::os;
 use std::old_io::fs::PathExtensions;
 use std::old_io::fs;
 
@@ -194,7 +195,7 @@ pub fn get_or_default_sysroot() -> Path {
             })
     }
 
-    match canonicalize(env::current_exe().ok()) {
+    match canonicalize(os::self_exe_name()) {
         Some(mut p) => { p.pop(); p.pop(); p }
         None => panic!("can't determine value for sysroot")
     }
@@ -224,7 +225,7 @@ pub fn rust_path() -> Vec<Path> {
         }
         None => Vec::new()
     };
-    let mut cwd = env::current_dir().unwrap();
+    let mut cwd = os::getcwd().unwrap();
     // now add in default entries
     let cwd_dot_rust = cwd.join(".rust");
     if !env_rust_path.contains(&cwd_dot_rust) {
@@ -243,7 +244,7 @@ pub fn rust_path() -> Vec<Path> {
         }
         cwd.pop();
     }
-    if let Some(h) = env::home_dir() {
+    if let Some(h) = os::homedir() {
         let p = h.join(".rust");
         if !env_rust_path.contains(&p) && p.exists() {
             env_rust_path.push(p);

src/librustc/plugin/load.rs

@@ -15,7 +15,7 @@ use metadata::creader::CrateReader;
 use plugin::registry::Registry;
 
 use std::mem;
-use std::env;
+use std::os;
 use std::dynamic_lib::DynamicLibrary;
 use std::borrow::ToOwned;
 use syntax::ast;
@@ -103,7 +103,7 @@ impl<'a> PluginLoader<'a> {
                         path: Path,
                         symbol: String) -> PluginRegistrarFun {
         // Make sure the path contains a / or the linker will search for it.
-        let path = env::current_dir().unwrap().join(&path);
+        let path = os::getcwd().unwrap().join(&path);
 
         let lib = match DynamicLibrary::open(Some(&path)) {
             Ok(lib) => lib,

src/librustc/session/mod.rs

@@ -27,8 +27,8 @@ use syntax::{ast, codemap};
 
 use rustc_back::target::Target;
 
-use std::env;
 use std::cell::{Cell, RefCell};
+use std::os;
 
 pub mod config;
 pub mod search_paths;
@@ -347,7 +347,7 @@ pub fn build_session_(sopts: config::Options,
         if path.is_absolute() {
             path.clone()
         } else {
-            env::current_dir().unwrap().join(&path)
+            os::getcwd().unwrap().join(&path)
         }
     );
 
@@ -370,7 +370,7 @@ pub fn build_session_(sopts: config::Options,
         plugin_registrar_fn: Cell::new(None),
         default_sysroot: default_sysroot,
         local_crate_source_file: local_crate_source_file,
-        working_dir: env::current_dir().unwrap(),
+        working_dir: os::getcwd().unwrap(),
         lint_store: RefCell::new(lint::LintStore::new()),
         lints: RefCell::new(NodeMap()),
         crate_types: RefCell::new(Vec::new()),

src/librustc_back/archive.rs

@@ -14,7 +14,7 @@ use std::old_io::fs::PathExtensions;
 use std::old_io::process::{Command, ProcessOutput};
 use std::old_io::{fs, TempDir};
 use std::old_io;
-use std::env;
+use std::os;
 use std::str;
 use syntax::diagnostic::Handler as ErrorHandler;
 
@@ -224,7 +224,7 @@ impl<'a> ArchiveBuilder<'a> {
     pub fn build(self) -> Archive<'a> {
         // Get an absolute path to the destination, so `ar` will work even
         // though we run it from `self.work_dir`.
-        let abs_dst = env::current_dir().unwrap().join(&self.archive.dst);
+        let abs_dst = os::getcwd().unwrap().join(&self.archive.dst);
         assert!(!abs_dst.is_relative());
         let mut args = vec![&abs_dst];
         let mut total_len = abs_dst.as_vec().len();
@@ -283,7 +283,7 @@ impl<'a> ArchiveBuilder<'a> {
         // First, extract the contents of the archive to a temporary directory.
         // We don't unpack directly into `self.work_dir` due to the possibility
         // of filename collisions.
-        let archive = env::current_dir().unwrap().join(archive);
+        let archive = os::getcwd().unwrap().join(archive);
         run_ar(self.archive.handler, &self.archive.maybe_ar_prog,
                "x", Some(loc.path()), &[&archive]);
 

src/librustc_back/fs.rs

@@ -10,13 +10,13 @@
 
 use std::old_io;
 use std::old_io::fs;
-use std::env;
+use std::os;
 
 /// Returns an absolute path in the filesystem that `path` points to. The
 /// returned path does not contain any symlinks in its hierarchy.
 pub fn realpath(original: &Path) -> old_io::IoResult<Path> {
     static MAX_LINKS_FOLLOWED: uint = 256;
-    let original = try!(env::current_dir()).join(original);
+    let original = try!(os::getcwd()).join(original);
 
     // Right now lstat on windows doesn't work quite well
     if cfg!(windows) {

src/librustc_back/lib.rs

@@ -41,6 +41,7 @@
 #![feature(rustc_private)]
 #![feature(staged_api)]
 #![feature(env)]
+#![feature(path)]
 
 extern crate syntax;
 extern crate serialize;

src/librustc_back/rpath.rs

@@ -8,10 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-
 use std::collections::HashSet;
 use std::env;
 use std::old_io::IoError;
+use std::os;
 use syntax::ast;
 
 pub struct RPathConfig<F, G> where
@@ -109,7 +109,7 @@ fn get_rpath_relative_to_output<F, G>(config: &mut RPathConfig<F, G>, lib: &Path
         "$ORIGIN"
     };
 
-    let cwd = env::current_dir().unwrap();
+    let cwd = os::getcwd().unwrap();
     let mut lib = (config.realpath)(&cwd.join(lib)).unwrap();
     lib.pop();
     let mut output = (config.realpath)(&cwd.join(&config.out_filename)).unwrap();
@@ -129,7 +129,7 @@ fn get_install_prefix_rpath<F, G>(config: RPathConfig<F, G>) -> String where
     let path = (config.get_install_prefix_lib_path)();
     let path = env::current_dir().unwrap().join(&path);
     // FIXME (#9639): This needs to handle non-utf8 paths
-    path.as_str().expect("non-utf8 component in rpath").to_string()
+    path.to_str().expect("non-utf8 component in rpath").to_string()
 }
 
 fn minimize_rpaths(rpaths: &[String]) -> Vec<String> {

src/librustc_back/target/mod.rs

@@ -310,6 +310,7 @@ impl Target {
     /// JSON decoding.
     pub fn search(target: &str) -> Result<Target, String> {
         use std::env;
+        use std::os;
         use std::ffi::OsString;
         use std::old_io::File;
         use std::old_path::Path;
@@ -396,7 +397,7 @@ impl Target {
 
         // FIXME 16351: add a sane default search path?
 
-        for dir in env::split_paths(&target_path) {
+        for dir in os::split_paths(target_path.to_str().unwrap()).iter() {
             let p =  dir.join(path.clone());
             if p.is_file() {
                 return load_file(&p);

src/librustc_driver/driver.rs

@@ -32,6 +32,7 @@ use super::Compilation;
 use serialize::json;
 
 use std::env;
+use std::os;
 use std::ffi::OsString;
 use std::old_io::fs;
 use std::old_io;
@@ -471,7 +472,7 @@ pub fn phase_2_configure_and_expand(sess: &Session,
             if cfg!(windows) {
                 _old_path = env::var_os("PATH").unwrap_or(_old_path);
                 let mut new_path = sess.host_filesearch(PathKind::All).get_dylib_search_paths();
-                new_path.extend(env::split_paths(&_old_path));
+                new_path.extend(os::split_paths(_old_path.to_str().unwrap()).into_iter());
                 env::set_var("PATH", &env::join_paths(new_path.iter()).unwrap());
             }
             let features = sess.features.borrow();
@@ -738,7 +739,7 @@ pub fn phase_6_link_output(sess: &Session,
                            outputs: &OutputFilenames) {
     let old_path = env::var_os("PATH").unwrap_or(OsString::from_str(""));
     let mut new_path = sess.host_filesearch(PathKind::All).get_tools_search_paths();
-    new_path.extend(env::split_paths(&old_path));
+    new_path.extend(os::split_paths(old_path.to_str().unwrap()).into_iter());
     env::set_var("PATH", &env::join_paths(new_path.iter()).unwrap());
 
     time(sess.time_passes(), "linking", (), |_|

src/librustdoc/test.rs

@@ -13,7 +13,7 @@ use std::sync::mpsc::channel;
 use std::dynamic_lib::DynamicLibrary;
 use std::old_io::{Command, TempDir};
 use std::old_io;
-use std::env;
+use std::os;
 use std::str;
 use std::thread;
 use std::thunk::Thunk;
@@ -46,7 +46,7 @@ pub fn run(input: &str,
     let input = config::Input::File(input_path.clone());
 
     let sessopts = config::Options {
-        maybe_sysroot: Some(env::current_exe().unwrap().dir_path().dir_path()),
+        maybe_sysroot: Some(os::self_exe_name().unwrap().dir_path().dir_path()),
         search_paths: libs.clone(),
         crate_types: vec!(config::CrateTypeDylib),
         externs: externs.clone(),
@@ -113,7 +113,7 @@ fn runtest(test: &str, cratename: &str, libs: SearchPaths,
     let input = config::Input::Str(test.to_string());
 
     let sessopts = config::Options {
-        maybe_sysroot: Some(env::current_exe().unwrap().dir_path().dir_path()),
+        maybe_sysroot: Some(os::self_exe_name().unwrap().dir_path().dir_path()),
         search_paths: libs,
         crate_types: vec!(config::CrateTypeExecutable),
         output_types: vec!(config::OutputTypeExe),

src/libstd/dynamic_lib.rs

@@ -21,6 +21,7 @@ use ffi::CString;
 use mem;
 use env;
 use str;
+use os;
 
 pub struct DynamicLibrary {
     handle: *mut u8
@@ -102,7 +103,7 @@ impl DynamicLibrary {
     /// process
     pub fn search_path() -> Vec<Path> {
         match env::var_os(DynamicLibrary::envvar()) {
-            Some(var) => env::split_paths(&var).collect(),
+            Some(var) => os::split_paths(var.to_str().unwrap()),
             None => Vec::new(),
         }
     }

src/libstd/env.rs

@@ -21,7 +21,8 @@ use prelude::v1::*;
 use error::Error;
 use ffi::{OsString, AsOsStr};
 use fmt;
-use old_io::IoResult;
+use io;
+use path::{AsPath, PathBuf};
 use sync::atomic::{AtomicIsize, ATOMIC_ISIZE_INIT, Ordering};
 use sync::{StaticMutex, MUTEX_INIT};
 use sys::os as os_imp;
@@ -46,7 +47,7 @@ use sys::os as os_imp;
 /// let p = env::current_dir().unwrap();
 /// println!("The current directory is {}", p.display());
 /// ```
-pub fn current_dir() -> IoResult<Path> {
+pub fn current_dir() -> io::Result<PathBuf> {
     os_imp::getcwd()
 }
 
@@ -57,14 +58,14 @@ pub fn current_dir() -> IoResult<Path> {
 ///
 /// ```rust
 /// use std::env;
-/// use std::old_path::Path;
+/// use std::path::Path;
 ///
 /// let root = Path::new("/");
 /// assert!(env::set_current_dir(&root).is_ok());
 /// println!("Successfully changed working directory to {}!", root.display());
 /// ```
-pub fn set_current_dir(p: &Path) -> IoResult<()> {
-    os_imp::chdir(p)
+pub fn set_current_dir<P: AsPath + ?Sized>(p: &P) -> io::Result<()> {
+    os_imp::chdir(p.as_path())
 }
 
 static ENV_LOCK: StaticMutex = MUTEX_INIT;
@@ -280,8 +281,8 @@ pub fn split_paths<T: AsOsStr + ?Sized>(unparsed: &T) -> SplitPaths {
 }
 
 impl<'a> Iterator for SplitPaths<'a> {
-    type Item = Path;
-    fn next(&mut self) -> Option<Path> { self.inner.next() }
+    type Item = PathBuf;
+    fn next(&mut self) -> Option<PathBuf> { self.inner.next() }
     fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
 }
 
@@ -305,10 +306,11 @@ pub struct JoinPathsError {
 ///
 /// ```rust
 /// use std::env;
+/// use std::path::PathBuf;
 ///
 /// if let Some(path) = env::var_os("PATH") {
 ///     let mut paths = env::split_paths(&path).collect::<Vec<_>>();
-///     paths.push(Path::new("/home/xyz/bin"));
+///     paths.push(PathBuf::new("/home/xyz/bin"));
 ///     let new_path = env::join_paths(paths.iter()).unwrap();
 ///     env::set_var("PATH", &new_path);
 /// }
@@ -355,7 +357,7 @@ impl Error for JoinPathsError {
 ///     None => println!("Impossible to get your home dir!")
 /// }
 /// ```
-pub fn home_dir() -> Option<Path> {
+pub fn home_dir() -> Option<PathBuf> {
     os_imp::home_dir()
 }
 
@@ -369,7 +371,7 @@ pub fn home_dir() -> Option<Path> {
 /// On Windows, returns the value of, in order, the 'TMP', 'TEMP',
 /// 'USERPROFILE' environment variable  if any are set and not the empty
 /// string. Otherwise, tmpdir returns the path to the Windows directory.
-pub fn temp_dir() -> Path {
+pub fn temp_dir() -> PathBuf {
     os_imp::temp_dir()
 }
 
@@ -396,7 +398,7 @@ pub fn temp_dir() -> Path {
 ///     Err(e) => println!("failed to get current exe path: {}", e),
 /// };
 /// ```
-pub fn current_exe() -> IoResult<Path> {
+pub fn current_exe() -> io::Result<PathBuf> {
     os_imp::current_exe()
 }
 
@@ -825,6 +827,7 @@ mod tests {
     use iter::repeat;
     use rand::{self, Rng};
     use ffi::{OsString, OsStr};
+    use path::PathBuf;
 
     fn make_rand_name() -> OsString {
         let mut rng = rand::thread_rng();
@@ -944,7 +947,7 @@ mod tests {
     fn split_paths_unix() {
         fn check_parse(unparsed: &str, parsed: &[&str]) -> bool {
             split_paths(unparsed).collect::<Vec<_>>() ==
-                parsed.iter().map(|s| Path::new(*s)).collect::<Vec<_>>()
+                parsed.iter().map(|s| PathBuf::new(*s)).collect::<Vec<_>>()
         }
 
         assert!(check_parse("", &mut [""]));

src/libstd/fs.rs → src/libstd/fs/mod.rs

@@ -25,6 +25,10 @@ use sys::fs2 as fs_imp;
 use sys_common::{AsInnerMut, FromInner, AsInner};
 use vec::Vec;
 
+pub use self::tempdir::TempDir;
+
+mod tempdir;
+
 /// A reference to an open file on the filesystem.
 ///
 /// An instance of a `File` can be read and/or written depending on what options