auto merge of #13183 : erickt/rust/remove-list, r=alexcrichton

`collections::list::List` was decided in a [team meeting](https://github.com/mozilla/rust/wiki/Meeting-weekly-2014-03-25) that it was unnecessary, so this PR removes it. Additionally, it removes an old and redundant purity test and fixes some warnings.

src/libarena/lib.rs

@@ -27,8 +27,6 @@
 
 extern crate collections;
 
-use collections::list::{List, Cons, Nil};
-
 use std::cast::{transmute, transmute_mut, transmute_mut_region};
 use std::cast;
 use std::cell::{Cell, RefCell};
@@ -87,7 +85,7 @@ pub struct Arena {
     // access the head.
     priv head: Chunk,
     priv copy_head: Chunk,
-    priv chunks: RefCell<@List<Chunk>>,
+    priv chunks: RefCell<Vec<Chunk>>,
 }
 
 impl Arena {
@@ -99,7 +97,7 @@ pub fn new_with_size(initial_size: uint) -> Arena {
         Arena {
             head: chunk(initial_size, false),
             copy_head: chunk(initial_size, true),
-            chunks: RefCell::new(@Nil),
+            chunks: RefCell::new(Vec::new()),
         }
     }
 }
@@ -117,7 +115,7 @@ impl Drop for Arena {
     fn drop(&mut self) {
         unsafe {
             destroy_chunk(&self.head);
-            for chunk in self.chunks.get().iter() {
+            for chunk in self.chunks.borrow().iter() {
                 if !chunk.is_copy.get() {
                     destroy_chunk(chunk);
                 }
@@ -179,7 +177,7 @@ fn chunk_size(&self) -> uint {
     fn alloc_copy_grow(&mut self, n_bytes: uint, align: uint) -> *u8 {
         // Allocate a new chunk.
         let new_min_chunk_size = cmp::max(n_bytes, self.chunk_size());
-        self.chunks.set(@Cons(self.copy_head.clone(), self.chunks.get()));
+        self.chunks.borrow_mut().push(self.copy_head.clone());
         self.copy_head =
             chunk(num::next_power_of_two(new_min_chunk_size + 1u), true);
 
@@ -219,7 +217,7 @@ fn alloc_noncopy_grow(&mut self, n_bytes: uint, align: uint)
                          -> (*u8, *u8) {
         // Allocate a new chunk.
         let new_min_chunk_size = cmp::max(n_bytes, self.chunk_size());
-        self.chunks.set(@Cons(self.head.clone(), self.chunks.get()));
+        self.chunks.borrow_mut().push(self.head.clone());
         self.head =
             chunk(num::next_power_of_two(new_min_chunk_size + 1u), false);
 

src/libcollections/lib.rs

@@ -33,7 +33,6 @@
 pub use dlist::DList;
 pub use enum_set::EnumSet;
 pub use hashmap::{HashMap, HashSet};
-pub use list::List;
 pub use lru_cache::LruCache;
 pub use priority_queue::PriorityQueue;
 pub use ringbuf::RingBuf;
@@ -47,7 +46,6 @@
 pub mod dlist;
 pub mod enum_set;
 pub mod hashmap;
-pub mod list;
 pub mod lru_cache;
 pub mod priority_queue;
 pub mod ringbuf;

src/libcollections/list.rs

-// Copyright 2012 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.
-
-//! A standard, garbage-collected linked list.
-
-use std::container::Container;
-
-#[deriving(Clone, Eq)]
-#[allow(missing_doc)]
-pub enum List<T> {
-    Cons(T, @List<T>),
-    Nil,
-}
-
-pub struct Items<'a, T> {
-    priv head: &'a List<T>,
-    priv next: Option<&'a @List<T>>
-}
-
-impl<'a, T> Iterator<&'a T> for Items<'a, T> {
-    fn next(&mut self) -> Option<&'a T> {
-        match self.next {
-            None => match *self.head {
-                Nil => None,
-                Cons(ref value, ref tail) => {
-                    self.next = Some(tail);
-                    Some(value)
-                }
-            },
-            Some(next) => match **next {
-                Nil => None,
-                Cons(ref value, ref tail) => {
-                    self.next = Some(tail);
-                    Some(value)
-                }
-            }
-        }
-    }
-}
-
-impl<T> List<T> {
-    /// Returns a forward iterator
-    pub fn iter<'a>(&'a self) -> Items<'a, T> {
-        Items {
-            head: self,
-            next: None
-        }
-    }
-
-    /// Returns the first element of a list
-    pub fn head<'a>(&'a self) -> Option<&'a T> {
-        match *self {
-          Nil => None,
-          Cons(ref head, _) => Some(head)
-        }
-    }
-
-    /// Returns all but the first element of a list
-    pub fn tail(&self) -> Option<@List<T>> {
-        match *self {
-            Nil => None,
-            Cons(_, tail) => Some(tail)
-        }
-    }
-}
-
-impl<T> Container for List<T> {
-    /// Returns the length of a list
-    fn len(&self) -> uint { self.iter().len() }
-
-    /// Returns true if the list is empty
-    fn is_empty(&self) -> bool { match *self { Nil => true, _ => false } }
-}
-
-impl<T:Eq> List<T> {
-    /// Returns true if a list contains an element with the given value
-    pub fn contains(&self, element: T) -> bool {
-        self.iter().any(|list_element| *list_element == element)
-    }
-}
-
-impl<T:'static + Clone> List<T> {
-    /// Create a list from a vector
-    pub fn from_vec(v: &[T]) -> List<T> {
-        match v.len() {
-            0 => Nil,
-            _ => v.rev_iter().fold(Nil, |tail, value: &T| Cons(value.clone(), @tail))
-        }
-    }
-
-    /// Appends one list to another, returning a new list
-    pub fn append(&self, other: List<T>) -> List<T> {
-        match other {
-            Nil => return self.clone(),
-            _ => match *self {
-                Nil => return other,
-                Cons(ref value, tail) => Cons(value.clone(), @tail.append(other))
-            }
-        }
-    }
-
-    /// Push one element into the front of a list, returning a new list
-    pub fn unshift(&self, element: T) -> List<T> {
-        Cons(element, @(self.clone()))
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use list::{List, Nil};
-    use list;
-
-    #[test]
-    fn test_iter() {
-        let list = List::from_vec([0, 1, 2]);
-        let mut iter = list.iter();
-        assert_eq!(&0, iter.next().unwrap());
-        assert_eq!(&1, iter.next().unwrap());
-        assert_eq!(&2, iter.next().unwrap());
-        assert_eq!(None, iter.next());
-    }
-
-    #[test]
-    fn test_is_empty() {
-        let empty : list::List<int> = List::from_vec([]);
-        let full1 = List::from_vec([1]);
-        let full2 = List::from_vec(['r', 'u']);
-
-        assert!(empty.is_empty());
-        assert!(!full1.is_empty());
-        assert!(!full2.is_empty());
-    }
-
-    #[test]
-    fn test_from_vec() {
-        let list = List::from_vec([0, 1, 2]);
-        assert_eq!(list.head().unwrap(), &0);
-
-        let mut tail = list.tail().unwrap();
-        assert_eq!(tail.head().unwrap(), &1);
-
-        tail = tail.tail().unwrap();
-        assert_eq!(tail.head().unwrap(), &2);
-    }
-
-    #[test]
-    fn test_from_vec_empty() {
-        let empty : list::List<int> = List::from_vec([]);
-        assert!(empty == Nil::<int>);
-    }
-
-    #[test]
-    fn test_fold() {
-        fn add_(a: uint, b: &uint) -> uint { a + *b }
-        fn subtract_(a: uint, b: &uint) -> uint { a - *b }
-
-        let empty = Nil::<uint>;
-        assert_eq!(empty.iter().fold(0u, add_), 0u);
-        assert_eq!(empty.iter().fold(10u, subtract_), 10u);
-
-        let list = List::from_vec([0u, 1u, 2u, 3u, 4u]);
-        assert_eq!(list.iter().fold(0u, add_), 10u);
-        assert_eq!(list.iter().fold(10u, subtract_), 0u);
-    }
-
-    #[test]
-    fn test_find_success() {
-        fn match_(i: & &int) -> bool { **i == 2 }
-
-        let list = List::from_vec([0, 1, 2]);
-        assert_eq!(list.iter().find(match_).unwrap(), &2);
-    }
-
-    #[test]
-    fn test_find_fail() {
-        fn match_(_i: & &int) -> bool { false }
-
-        let empty = Nil::<int>;
-        assert_eq!(empty.iter().find(match_), None);
-
-        let list = List::from_vec([0, 1, 2]);
-        assert_eq!(list.iter().find(match_), None);
-    }
-
-    #[test]
-    fn test_any() {
-        fn match_(i: &int) -> bool { *i == 2 }
-
-        let empty = Nil::<int>;
-        assert_eq!(empty.iter().any(match_), false);
-
-        let list = List::from_vec([0, 1, 2]);
-        assert_eq!(list.iter().any(match_), true);
-    }
-
-    #[test]
-    fn test_contains() {
-        let empty = Nil::<int>;
-        assert!((!empty.contains(5)));
-
-        let list = List::from_vec([5, 8, 6]);
-        assert!((list.contains(5)));
-        assert!((!list.contains(7)));
-        assert!((list.contains(8)));
-    }
-
-    #[test]
-    fn test_len() {
-        let empty = Nil::<int>;
-        assert_eq!(empty.len(), 0u);
-
-        let list = List::from_vec([0, 1, 2]);
-        assert_eq!(list.len(), 3u);
-    }
-
-    #[test]
-    fn test_append() {
-        assert!(List::from_vec([1, 2, 3, 4]) ==
-                List::from_vec([1, 2]).append(List::from_vec([3, 4])));
-    }
-
-    #[test]
-    fn test_unshift() {
-        let list = List::from_vec([1]);
-        let new_list = list.unshift(0);
-        assert_eq!(list.len(), 1u);
-        assert_eq!(new_list.len(), 2u);
-        assert!(new_list == List::from_vec([0, 1]));
-    }
-}

src/libgreen/sched.rs

@@ -1473,7 +1473,7 @@ fn test_spawn_sched_blocking() {
             let mut handle = pool.spawn_sched();
             handle.send(PinnedTask(pool.task(TaskOpts::new(), proc() {
                 unsafe {
-                    let mut guard = LOCK.lock();
+                    let guard = LOCK.lock();
 
                     start_tx.send(());
                     guard.wait();   // block the scheduler thread
@@ -1509,7 +1509,7 @@ fn pingpong(po: &Receiver<int>, ch: &Sender<int>) {
                 child_tx.send(20);
                 pingpong(&parent_rx, &child_tx);
                 unsafe {
-                    let mut guard = LOCK.lock();
+                    let guard = LOCK.lock();
                     guard.signal();   // wakeup waiting scheduler
                     guard.wait();     // wait for them to grab the lock
                 }

src/librustc/middle/typeck/mod.rs

@@ -72,7 +72,6 @@
 
 use std::cell::RefCell;
 use std::rc::Rc;
-use collections::List;
 use syntax::codemap::Span;
 use syntax::print::pprust::*;
 use syntax::{ast, ast_map, abi};
@@ -327,7 +326,7 @@ pub fn require_same_types(tcx: &ty::ctxt,
 
 // a list of mapping from in-scope-region-names ("isr") to the
 // corresponding ty::Region
-pub type isr_alist = @List<(ty::BoundRegion, ty::Region)>;
+pub type isr_alist = @Vec<(ty::BoundRegion, ty::Region)>;
 
 trait get_region<'a, T:'static> {
     fn get(&'a self, br: ty::BoundRegion) -> ty::Region;

src/libstd/iter.rs

@@ -2335,7 +2335,7 @@ mod tests {
 
     #[test]
     fn test_counter_from_iter() {
-        let mut it = count(0, 5).take(10);
+        let it = count(0, 5).take(10);
         let xs: ~[int] = FromIterator::from_iterator(it);
         assert_eq!(xs, ~[0, 5, 10, 15, 20, 25, 30, 35, 40, 45]);
     }

src/libstd/str.rs

@@ -3218,7 +3218,7 @@ fn test_extend() {
         let data = ~"ประเทศไทย中";
         let mut cpy = data.clone();
         let other = "abc";
-        let mut it = other.chars();
+        let it = other.chars();
         cpy.extend(it);
         assert_eq!(cpy, data + other);
     }

src/libstd/unstable/mutex.rs

@@ -621,7 +621,7 @@ fn smoke_cond_noguard() {
     #[test]
     fn destroy_immediately() {
         unsafe {
-            let mut m = StaticNativeMutex::new();
+            let m = StaticNativeMutex::new();
             m.destroy();
         }
     }

src/test/bench/task-perf-alloc-unwind.rs

@@ -13,12 +13,16 @@
 extern crate collections;
 extern crate time;
 
-use collections::list::{List, Cons, Nil};
 use time::precise_time_s;
 use std::os;
 use std::task;
 use std::vec;
 
+#[deriving(Clone)]
+enum List<T> {
+    Nil, Cons(T, @List<T>)
+}
+
 enum UniqueList {
     ULNil, ULCons(~UniqueList)
 }

src/test/run-pass/log-knows-the-names-of-variants-in-std.rs

@@ -10,9 +10,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-extern crate collections;
-use collections::list::List;
-
 #[deriving(Clone)]
 enum foo {
   a(uint),
@@ -24,9 +21,21 @@ fn check_log<T>(exp: ~str, v: T) {
 }
 
 pub fn main() {
-    let x = List::from_vec([a(22u), b(~"hi")]);
-    let exp = ~"Cons(a(22u), @Cons(b(~\"hi\"), @Nil))";
+    let mut x = Some(a(22u));
+    let exp = ~"Some(a(22u))";
+    let act = format!("{:?}", x);
+    assert_eq!(act, exp);
+    check_log(exp, x);
+
+    x = Some(b(~"hi"));
+    let exp = ~"Some(b(~\"hi\"))";
+    let act = format!("{:?}", x);
+    assert_eq!(act, exp);
+    check_log(exp, x);
+
+    x = None;
+    let exp = ~"None";
     let act = format!("{:?}", x);
-    assert!(act == exp);
+    assert_eq!(act, exp);
     check_log(exp, x);
 }

src/test/run-pass/non-boolean-pure-fns.rs

-// ignore-fast
-
-// Copyright 2012-2014 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.
-
-#[feature(managed_boxes)];
-
-extern crate collections;
-
-use collections::list::{List, Cons, Nil};
-
-fn pure_length_go<T>(ls: @List<T>, acc: uint) -> uint {
-    match *ls { Nil => { acc } Cons(_, tl) => { pure_length_go(tl, acc + 1u) } }
-}
-
-fn pure_length<T>(ls: @List<T>) -> uint { pure_length_go(ls, 0u) }
-
-fn nonempty_list<T>(ls: @List<T>) -> bool { pure_length(ls) > 0u }
-
-fn safe_head<T:Clone>(ls: @List<T>) -> T {
-    assert!(!ls.is_empty());
-    return ls.head().unwrap().clone();
-}
-
-pub fn main() {
-    let mylist = @Cons(@1u, @Nil);
-    assert!((nonempty_list(mylist)));
-    assert_eq!(*safe_head(mylist), 1u);
-}