auto merge of #5570 : alexcrichton/rust/fix-unused-imports, r=sanxiyn

Before it wouldn't warn about unused imports in the list if something in the list was used. These commits fix that case, add a test, and remove all unused imports in lists of imports throughout the compiler.

Author: bors

Diff for: doc/tutorial-tasks.md

@@ -188,7 +188,7 @@ spawns the child task.
 
 ~~~~
 # use core::task::spawn;
-# use core::comm::{stream, Port, Chan};
+# use core::comm::stream;
 # fn some_expensive_computation() -> int { 42 }
 # let (port, chan) = stream();
 do spawn || {
@@ -208,7 +208,7 @@ computation, then waits for the child's result to arrive on the
 port:
 
 ~~~~
-# use core::comm::{stream, Port, Chan};
+# use core::comm::{stream};
 # fn some_other_expensive_computation() {}
 # let (port, chan) = stream::<int>();
 # chan.send(0);
@@ -277,7 +277,7 @@ might look like the example below.
 
 ~~~
 # use core::task::spawn;
-# use core::comm::{stream, Port, Chan};
+# use core::comm::stream;
 
 // Create a vector of ports, one for each child task
 let ports = do vec::from_fn(3) |init_val| {

Diff for: src/compiletest/procsrv.rs

@@ -12,7 +12,7 @@ use core::prelude::*;
 
 use core::io::{ReaderUtil, WriterUtil};
 use core::io;
-use core::libc::{c_int, pid_t};
+use core::libc::c_int;
 use core::os;
 use core::run::spawn_process;
 use core::run;

Diff for: src/libcore/cleanup.rs

@@ -11,11 +11,13 @@
 #[doc(hidden)];
 
 use libc::{c_char, c_void, intptr_t, uintptr_t};
-use ptr::{mut_null, null, to_unsafe_ptr};
+use ptr::mut_null;
 use repr::BoxRepr;
 use sys::TypeDesc;
 use cast::transmute;
 
+#[cfg(notest)] use ptr::to_unsafe_ptr;
+
 /**
  * Runtime structures
  *

Diff for: src/libcore/comm.rs

@@ -429,7 +429,7 @@ pub fn try_send_one<T: Owned>(chan: ChanOne<T>, data: T)
 
 #[cfg(test)]
 pub mod test {
-    use either::{Either, Left, Right};
+    use either::Right;
     use super::{Chan, Port, oneshot, recv_one, stream};
 
     #[test]

Diff for: src/libcore/gc.rs

@@ -38,7 +38,7 @@ with destructors.
 */
 
 use cast;
-use container::{Container, Mutable, Map, Set};
+use container::{Map, Set};
 use io;
 use libc::{size_t, uintptr_t};
 use option::{None, Option, Some};

Diff for: src/libcore/hash.rs

@@ -20,7 +20,7 @@
  */
 
 use io;
-use io::{Writer, WriterUtil};
+use io::Writer;
 use to_bytes::IterBytes;
 use uint;
 use vec;

Diff for: src/libcore/hashmap.rs

@@ -667,7 +667,7 @@ pub mod linear {
 
     #[test]
     mod test_map {
-        use container::{Container, Mutable, Map, Set};
+        use container::{Container, Map, Set};
         use option::{None, Some};
         use hashmap::linear::LinearMap;
         use hashmap::linear;
@@ -845,7 +845,7 @@ pub mod linear {
 #[test]
     mod test_set {
         use hashmap::linear;
-        use container::{Container, Mutable, Map, Set};
+        use container::{Container, Map, Set};
         use vec;
 
         #[test]

Diff for: src/libcore/io.rs

@@ -18,7 +18,7 @@ use result::Result;
 
 use int;
 use libc;
-use libc::{c_int, c_long, c_uint, c_void, size_t, ssize_t};
+use libc::{c_int, c_long, c_void, size_t, ssize_t};
 use libc::consts::os::posix88::*;
 use os;
 use cast;

Diff for: src/libcore/num/float.rs

@@ -24,12 +24,13 @@ use f64;
 use num::NumCast;
 use num::strconv;
 use num;
-use option::{None, Option, Some};
+use option::Option;
 use to_str;
 use from_str;
 
 #[cfg(notest)] use cmp::{Eq, Ord};
 #[cfg(notest)] use ops;
+#[cfg(test)] use option::{Some, None};
 
 pub use f64::{add, sub, mul, div, rem, lt, le, eq, ne, ge, gt};
 pub use f64::logarithm;

Diff for: src/libcore/num/num.rs

@@ -9,9 +9,9 @@
 // except according to those terms.
 
 //! An interface for numeric types
-use cmp::{Ord, Eq};
-use ops::{Add, Div, Modulo, Mul, Neg, Sub};
-use option::{None, Option, Some};
+use cmp::Ord;
+use ops::{Div, Mul, Neg};
+use option::Option;
 use kinds::Copy;
 
 pub mod strconv;

Diff for: src/libcore/num/uint-template.rs

@@ -16,7 +16,7 @@ use from_str::FromStr;
 use num::{ToStrRadix, FromStrRadix};
 use num::strconv;
 use num;
-use option::{None, Option, Some};
+use option::Option;
 use prelude::*;
 
 #[cfg(notest)] use cmp::{Eq, Ord};

Diff for: src/libcore/os.rs

@@ -29,7 +29,7 @@
 use cast;
 use io;
 use libc;
-use libc::{c_char, c_void, c_int, c_uint, size_t, ssize_t};
+use libc::{c_char, c_void, c_int, size_t};
 use libc::{mode_t, pid_t, FILE};
 use option;
 use option::{Some, None};
@@ -397,7 +397,7 @@ pub fn pipe() -> Pipe {
         // first, as in rust_run_program.
         let mut fds = Pipe {in: 0 as c_int,
                     out: 0 as c_int };
-        let res = libc::pipe(&mut fds.in, 1024 as c_uint,
+        let res = libc::pipe(&mut fds.in, 1024 as ::libc::c_uint,
                              (libc::O_BINARY | libc::O_NOINHERIT) as c_int);
         fail_unless!((res == 0 as c_int));
         fail_unless!((fds.in != -1 as c_int && fds.in != 0 as c_int));
@@ -431,7 +431,7 @@ pub fn self_exe_path() -> Option<Path> {
                            KERN_PROC as c_int,
                            KERN_PROC_PATHNAME as c_int, -1 as c_int];
                 let mut sz = sz;
-                sysctl(vec::raw::to_ptr(mib), vec::len(mib) as c_uint,
+                sysctl(vec::raw::to_ptr(mib), vec::len(mib) as ::libc::c_uint,
                        buf as *mut c_void, &mut sz, ptr::null(),
                        0u as size_t) == (0 as c_int)
             }
@@ -670,7 +670,7 @@ pub fn list_dir(p: &Path) -> ~[~str] {
         #[cfg(target_os = "freebsd")]
         #[cfg(target_os = "macos")]
         unsafe fn get_list(p: &Path) -> ~[~str] {
-            use libc::{DIR, dirent_t};
+            use libc::{dirent_t};
             use libc::{opendir, readdir, closedir};
             extern mod rustrt {
                 unsafe fn rust_list_dir_val(ptr: *dirent_t)
@@ -1257,7 +1257,7 @@ pub mod consts {
 mod tests {
     use libc::{c_int, c_void, size_t};
     use libc;
-    use option::{None, Option, Some};
+    use option::Some;
     use option;
     use os::{as_c_charp, env, getcwd, getenv, make_absolute, real_args};
     use os::{remove_file, setenv};

Diff for: src/libcore/pipes.rs

@@ -958,9 +958,9 @@ pub mod rt {
 
 #[cfg(test)]
 pub mod test {
-    use either::{Either, Left, Right};
+    use either::Right;
     use comm::{Chan, Port, oneshot, recv_one, stream, Select2,
-               GenericPort, GenericChan, Peekable};
+               GenericChan, Peekable};
 
     #[test]
     pub fn test_select2() {

Diff for: src/libcore/ptr.rs

@@ -13,7 +13,6 @@
 use cast;
 use libc;
 use libc::{c_void, size_t};
-use unstable::intrinsics::{memmove32,memmove64};
 use sys;
 
 #[cfg(test)] use vec;
@@ -116,12 +115,14 @@ pub fn is_not_null<T>(ptr: *const T) -> bool { !is_null(ptr) }
 #[inline(always)]
 #[cfg(target_word_size = "32")]
 pub unsafe fn copy_memory<T>(dst: *mut T, src: *const T, count: uint) {
+    use unstable::intrinsics::memmove32;
     let n = count * sys::size_of::<T>();
     memmove32(dst as *mut u8, src as *u8, n as u32);
 }
 #[inline(always)]
 #[cfg(target_word_size = "64")]
 pub unsafe fn copy_memory<T>(dst: *mut T, src: *const T, count: uint) {
+    use unstable::intrinsics::memmove64;
     let n = count * sys::size_of::<T>();
     memmove64(dst as *mut u8, src as *u8, n as u64);
 }

Diff for: src/libcore/rand.rs

@@ -574,7 +574,7 @@ pub fn random() -> uint {
 
 #[cfg(test)]
 pub mod tests {
-    use option::{None, Option, Some};
+    use option::{Option, Some};
     use rand;
 
     #[test]

Diff for: src/libcore/reflect.rs

@@ -14,7 +14,7 @@ Runtime type reflection
 
 */
 
-use intrinsic::{TyDesc, get_tydesc, visit_tydesc, TyVisitor};
+use intrinsic::{TyDesc, TyVisitor};
 use libc::c_void;
 use sys;
 use vec;

Diff for: src/libcore/repr.rs

@@ -23,7 +23,7 @@ use libc::c_void;
 use managed;
 use ptr;
 use reflect;
-use reflect::{MovePtr, MovePtrAdaptor, align};
+use reflect::{MovePtr, align};
 use sys;
 use to_str::ToStr;
 use vec::UnboxedVecRepr;

Diff for: src/libcore/rt/io/file.rs

@@ -9,8 +9,6 @@
 // except according to those terms.
 
 use prelude::*;
-use super::super::sched::*;
-use super::super::rtio::*;
 use super::Stream;
 
 pub struct FileStream;

Diff for: src/libcore/rt/thread_local_storage.rs

@@ -8,9 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use libc::{c_void};
+use libc::c_void;
 #[cfg(unix)]
-use libc::{c_uint, c_ulong, c_int};
+use libc::c_int;
 #[cfg(unix)]
 use ptr::null;
 #[cfg(windows)]
@@ -36,13 +36,13 @@ pub unsafe fn get(key: Key) -> *mut c_void {
 
 #[cfg(target_os="macos")]
 #[allow(non_camel_case_types)] // foreign type
-type pthread_key_t = c_ulong;
+type pthread_key_t = ::libc::c_ulong;
 
 #[cfg(target_os="linux")]
 #[cfg(target_os="freebsd")]
 #[cfg(target_os="android")]
 #[allow(non_camel_case_types)] // foreign type
-type pthread_key_t = c_uint;
+type pthread_key_t = ::libc::c_uint;
 
 #[cfg(unix)]
 extern {

Diff for: src/libcore/rt/uv/mod.rs

@@ -39,16 +39,13 @@ use str::raw::from_c_str;
 use to_str::ToStr;
 use vec;
 use ptr;
-use libc::{c_void, c_int, size_t, malloc, free, ssize_t};
-use cast::{transmute, transmute_mut_region};
+use libc::{c_void, c_int, size_t, malloc, free};
+use cast::transmute;
 use ptr::null;
 use super::uvll;
-use super::uvll::*;
 use unstable::finally::Finally;
 
 #[cfg(test)] use unstable::run_in_bare_thread;
-#[cfg(test)] use super::thread::Thread;
-#[cfg(test)] use cell::Cell;
 
 pub use self::file::{FsRequest, FsCallback};
 pub use self::net::{StreamWatcher, TcpWatcher};

Diff for: src/libcore/rt/uv/net.rs

@@ -10,7 +10,7 @@
 
 use prelude::*;
 use libc::{size_t, ssize_t, c_int, c_void};
-use cast::{transmute, transmute_mut_region};
+use cast::transmute_mut_region;
 use super::super::uvll;
 use super::super::uvll::*;
 use super::{Loop, Watcher, Request, UvError, Buf, Callback, NativeHandle, NullCallback,

Diff for: src/libcore/run.rs

@@ -458,7 +458,7 @@ pub fn waitpid(pid: pid_t) -> int {
 
 #[cfg(test)]
 mod tests {
-    use option::{None, Some};
+    use option::None;
     use os;
     use run::{readclose, writeclose};
     use run;

Diff for: src/libcore/str.rs

@@ -21,7 +21,7 @@ use at_vec;
 use cast;
 use char;
 use clone::Clone;
-use cmp::{Equiv, TotalEq, TotalOrd, Ordering, Less, Equal, Greater};
+use cmp::{TotalOrd, Ordering, Less, Equal, Greater};
 use libc;
 use option::{None, Option, Some};
 use ptr;
@@ -31,7 +31,7 @@ use uint;
 use vec;
 use to_str::ToStr;
 
-#[cfg(notest)] use cmp::{Eq, Ord};
+#[cfg(notest)] use cmp::{Eq, Ord, Equiv, TotalEq};
 
 /*
 Section: Creating a string

Diff for: src/libcore/task/mod.rs

@@ -36,13 +36,15 @@
 use cell::Cell;
 use cmp::Eq;
 use result::Result;
-use comm::{stream, Chan, GenericChan, GenericPort, Port, SharedChan};
+use comm::{stream, Chan, GenericChan, GenericPort, Port};
 use prelude::*;
 use result;
 use task::rt::{task_id, sched_id, rust_task};
 use util;
 use util::replace;
 
+#[cfg(test)] use comm::SharedChan;
+
 mod local_data_priv;
 pub mod local_data;
 pub mod rt;

Diff for: src/libcore/task/spawn.rs

@@ -75,7 +75,7 @@
 use cast;
 use cell::Cell;
 use container::Map;
-use comm::{Chan, GenericChan, GenericPort, Port, stream};
+use comm::{Chan, GenericChan};
 use prelude::*;
 use unstable;
 use ptr;
@@ -86,10 +86,12 @@ use task::rt;
 use task::{Failure, ManualThreads, PlatformThread, SchedOpts, SingleThreaded};
 use task::{Success, TaskOpts, TaskResult, ThreadPerCore, ThreadPerTask};
 use task::{ExistingScheduler, SchedulerHandle};
-use task::{default_task_opts, unkillable};
+use task::unkillable;
 use uint;
 use util;
 
+#[cfg(test)] use task::default_task_opts;
+
 macro_rules! move_it (
     { $x:expr } => ( unsafe { let y = *ptr::addr_of(&($x)); y } )
 )

Diff for: src/libcore/unstable.rs

@@ -15,7 +15,7 @@ use libc;
 use comm::{GenericChan, GenericPort};
 use prelude::*;
 use task;
-use task::{TaskBuilder, atomically};
+use task::atomically;
 
 #[path = "unstable/at_exit.rs"]
 pub mod at_exit;

Diff for: src/libcore/unstable/at_exit.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use cast;
-use libc::{c_void, size_t};
+use libc::size_t;
 use rand::RngUtil;
 use rand;
 use sys;