auto merge of #14613 : schmee/rust/utf16-iterator, r=huonw

Closes #14358.

~~The tests are not yet moved to `utf16_iter`, so this probably won't compile. I'm submitting this PR anyway so it can be reviewed and since it was mentioned in #14611.~~ EDIT: Tests now use `utf16_iter`.

This deprecates `.to_utf16`. `x.to_utf16()` should be replaced by either `x.utf16_iter().collect::<Vec<u16>>()` (the type annotation may be optional), or just `x.utf16_iter()` directly, if it can be used in an iterator context.

[breaking-change]

cc @huonw

3 files changed, 14 insertions, 6 deletions

diff --git a/src/libnative/io/c_win32.rs b/src/libnative/io/c_win32.rs
index 7e58102d241..802526c9196 100644
--- a/src/libnative/io/c_win32.rs
+++ b/src/libnative/io/c_win32.rs
@@ -70,6 +70,7 @@ extern "system" {
 
 pub mod compat {
     use std::intrinsics::{atomic_store_relaxed, transmute};
+    use std::iter::Iterator;
     use libc::types::os::arch::extra::{LPCWSTR, HMODULE, LPCSTR, LPVOID};
 
     extern "system" {
@@ -82,7 +83,8 @@ pub mod compat {
     // layer (after it's loaded) shouldn't be any slower than a regular DLL
     // call.
     unsafe fn store_func(ptr: *mut uint, module: &str, symbol: &str, fallback: uint) {
-        let module = module.to_utf16().append_one(0);
+        let module: Vec<u16> = module.utf16_units().collect();
+        let module = module.append_one(0);
         symbol.with_c_str(|symbol| {
             let handle = GetModuleHandleW(module.as_ptr());
             let func: uint = transmute(GetProcAddress(handle, symbol));
diff --git a/src/libnative/io/file_win32.rs b/src/libnative/io/file_win32.rs
index 3195fa4f2d4..98553603313 100644
--- a/src/libnative/io/file_win32.rs
+++ b/src/libnative/io/file_win32.rs
@@ -255,7 +255,7 @@ impl Drop for Inner {
 
 pub fn to_utf16(s: &CString) -> IoResult<Vec<u16>> {
     match s.as_str() {
-        Some(s) => Ok(s.to_utf16().append_one(0)),
+        Some(s) => Ok(s.utf16_units().collect::<Vec<u16>>().append_one(0)),
         None => Err(IoError {
             code: libc::ERROR_INVALID_NAME as uint,
             extra: 0,
diff --git a/src/libnative/io/process.rs b/src/libnative/io/process.rs
index b1c0d9a1506..6fab73115cf 100644
--- a/src/libnative/io/process.rs
+++ b/src/libnative/io/process.rs
@@ -294,6 +294,8 @@ fn spawn_process_os(cfg: ProcessConfig,
     use libc::funcs::extra::msvcrt::get_osfhandle;
 
     use std::mem;
+    use std::iter::Iterator;
+    use std::str::StrSlice;
 
     if cfg.gid.is_some() || cfg.uid.is_some() {
         return Err(IoError {
@@ -328,7 +330,8 @@ fn spawn_process_os(cfg: ProcessConfig,
                         lpSecurityDescriptor: ptr::mut_null(),
                         bInheritHandle: 1,
                     };
-                    let filename = "NUL".to_utf16().append_one(0);
+                    let filename: Vec<u16> = "NUL".utf16_units().collect();
+                    let filename = filename.append_one(0);
                     *slot = libc::CreateFileW(filename.as_ptr(),
                                               access,
                                               libc::FILE_SHARE_READ |
@@ -371,7 +374,8 @@ fn spawn_process_os(cfg: ProcessConfig,
 
         with_envp(cfg.env, |envp| {
             with_dirp(cfg.cwd, |dirp| {
-                let mut cmd_str = cmd_str.to_utf16().append_one(0);
+                let mut cmd_str: Vec<u16> = cmd_str.as_slice().utf16_units().collect();
+                cmd_str = cmd_str.append_one(0);
                 let created = CreateProcessW(ptr::null(),
                                              cmd_str.as_mut_ptr(),
                                              ptr::mut_null(),
@@ -770,7 +774,7 @@ fn with_envp<T>(env: Option<&[(CString, CString)]>, cb: |*mut c_void| -> T) -> T
                 let kv = format!("{}={}",
                                  pair.ref0().as_str().unwrap(),
                                  pair.ref1().as_str().unwrap());
-                blk.push_all(kv.to_utf16().as_slice());
+                blk.extend(kv.as_slice().utf16_units());
                 blk.push(0);
             }
 
@@ -788,7 +792,9 @@ fn with_dirp<T>(d: Option<&CString>, cb: |*const u16| -> T) -> T {
       Some(dir) => {
           let dir_str = dir.as_str()
                            .expect("expected workingdirectory to be utf-8 encoded");
-          let dir_str = dir_str.to_utf16().append_one(0);
+          let dir_str: Vec<u16> = dir_str.utf16_units().collect();
+          let dir_str = dir_str.append_one(0);
+
           cb(dir_str.as_ptr())
       },
       None => cb(ptr::null())