auto merge of #12626 : alexcrichton/rust/assert-eq, r=thestinger

Formatting via reflection has been a little questionable for some time now, and
it's a little unfortunate that one of the standard macros will silently use
reflection when you weren't expecting it. This adds small bits of code bloat to
libraries, as well as not always being necessary. In light of this information,
this commit switches assert_eq!() to using {} in the error message instead of
{:?}.

In updating existing code, there were a few error cases that I encountered:

* It's impossible to define Show for [T, ..N]. I think DST will alleviate this
  because we can define Show for [T].
* A few types here and there just needed a #[deriving(Show)]
* Type parameters needed a Show bound, I often moved this to `assert!(a == b)`
* `Path` doesn't implement `Show`, so assert_eq!() cannot be used on two paths.
  I don't think this is much of a regression though because {:?} on paths looks
  awful (it's a byte array).

Concretely speaking, this shaved 10K off a 656K binary. Not a lot, but sometime
significant for smaller binaries.

Author: bors

src/doc/guide-container.md

@@ -384,7 +384,7 @@ the trailing underscore is a workaround for issue #5898 and will be removed.
 ~~~
 let mut ys = [1, 2, 3, 4, 5];
 ys.mut_iter().reverse_();
-assert_eq!(ys, [5, 4, 3, 2, 1]);
+assert!(ys == [5, 4, 3, 2, 1]);
 ~~~
 
 ## Random-access iterators

src/doc/tutorial.md

@@ -1688,7 +1688,7 @@ let x = Rc::new([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
 let y = x.clone(); // a new owner
 let z = x; // this moves `x` into `z`, rather than creating a new owner
 
-assert_eq!(*z.borrow(), [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
+assert!(*z.borrow() == [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
 
 // the variable is mutable, but not the contents of the box
 let mut a = Rc::new([10, 9, 8, 7, 6, 5, 4, 3, 2, 1]);
@@ -1707,7 +1707,7 @@ let x = Gc::new([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
 let y = x; // does not perform a move, unlike with `Rc`
 let z = x;
 
-assert_eq!(*z.borrow(), [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
+assert!(*z.borrow() == [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
 ~~~
 
 With shared ownership, mutability cannot be inherited so the boxes are always immutable. However,

src/libcollections/bitv.rs

@@ -1542,7 +1542,7 @@ mod tests {
 
         let mut b = a.clone();
 
-        assert_eq!(&a, &b);
+        assert!(a == b);
 
         assert!(b.remove(&1));
         assert!(a.contains(&1));
@@ -1561,7 +1561,7 @@ mod tests {
         let mut r = rng();
         let mut bitv = 0 as uint;
         b.iter(|| {
-            bitv |= (1 << ((r.next_u32() as uint) % uint::BITS));
+            bitv |= 1 << ((r.next_u32() as uint) % uint::BITS);
             &bitv
         })
     }

src/libcollections/dlist.rs

@@ -982,11 +982,11 @@ mod tests {
     fn test_eq() {
         let mut n: DList<u8> = list_from([]);
         let mut m = list_from([]);
-        assert_eq!(&n, &m);
+        assert!(n == m);
         n.push_front(1);
         assert!(n != m);
         m.push_back(1);
-        assert_eq!(&n, &m);
+        assert!(n == m);
 
         let n = list_from([2,3,4]);
         let m = list_from([1,2,3]);

src/libcollections/enum_set.rs

@@ -141,7 +141,7 @@ mod test {
 
     use enum_set::{EnumSet, CLike};
 
-    #[deriving(Eq)]
+    #[deriving(Eq, Show)]
     #[repr(uint)]
     enum Foo {
         A, B, C

src/libcollections/hashmap.rs

@@ -1065,7 +1065,7 @@ mod test_map {
         let mut observed = 0;
         for (k, v) in m.iter() {
             assert_eq!(*v, *k * 2);
-            observed |= (1 << *k);
+            observed |= 1 << *k;
         }
         assert_eq!(observed, 0xFFFF_FFFF);
     }
@@ -1293,7 +1293,7 @@ mod test_set {
         }
         let mut observed = 0;
         for k in a.iter() {
-            observed |= (1 << *k);
+            observed |= 1 << *k;
         }
         assert_eq!(observed, 0xFFFF_FFFF);
     }

src/libcollections/list.rs

@@ -153,7 +153,7 @@ mod tests {
     #[test]
     fn test_from_vec_empty() {
         let empty : list::List<int> = List::from_vec([]);
-        assert_eq!(empty, Nil::<int>);
+        assert!(empty == Nil::<int>);
     }
 
     #[test]
@@ -222,8 +222,8 @@ mod tests {
 
     #[test]
     fn test_append() {
-        assert_eq!(List::from_vec([1, 2, 3, 4]),
-                   List::from_vec([1, 2]).append(List::from_vec([3, 4])));
+        assert!(List::from_vec([1, 2, 3, 4]) ==
+                List::from_vec([1, 2]).append(List::from_vec([3, 4])));
     }
 
     #[test]
@@ -232,6 +232,6 @@ mod tests {
         let new_list = list.unshift(0);
         assert_eq!(list.len(), 1u);
         assert_eq!(new_list.len(), 2u);
-        assert_eq!(new_list, List::from_vec([0, 1]));
+        assert!(new_list == List::from_vec([0, 1]));
     }
 }

src/libcollections/lru_cache.rs

@@ -277,7 +277,7 @@ mod tests {
 
     fn assert_opt_eq<V: Eq>(opt: Option<&V>, v: V) {
         assert!(opt.is_some());
-        assert_eq!(opt.unwrap(), &v);
+        assert!(opt.unwrap() == &v);
     }
 
     #[test]

src/libcollections/ringbuf.rs

@@ -409,6 +409,7 @@ mod tests {
     use deque::Deque;
     use std::clone::Clone;
     use std::cmp::Eq;
+    use std::fmt::Show;
     use super::RingBuf;
 
     #[test]
@@ -493,7 +494,7 @@ mod tests {
     }
 
     #[cfg(test)]
-    fn test_parameterized<T:Clone + Eq>(a: T, b: T, c: T, d: T) {
+    fn test_parameterized<T:Clone + Eq + Show>(a: T, b: T, c: T, d: T) {
         let mut deq = RingBuf::new();
         assert_eq!(deq.len(), 0);
         deq.push_front(a.clone());
@@ -578,21 +579,21 @@ mod tests {
         })
     }
 
-    #[deriving(Clone, Eq)]
+    #[deriving(Clone, Eq, Show)]
     enum Taggy {
         One(int),
         Two(int, int),
         Three(int, int, int),
     }
 
-    #[deriving(Clone, Eq)]
+    #[deriving(Clone, Eq, Show)]
     enum Taggypar<T> {
         Onepar(int),
         Twopar(int, int),
         Threepar(int, int, int),
     }
 
-    #[deriving(Clone, Eq)]
+    #[deriving(Clone, Eq, Show)]
     struct RecCy {
         x: int,
         y: int,
@@ -812,7 +813,7 @@ mod tests {
     #[test]
     fn test_eq() {
         let mut d = RingBuf::new();
-        assert_eq!(&d, &RingBuf::with_capacity(0));
+        assert!(d == RingBuf::with_capacity(0));
         d.push_front(137);
         d.push_front(17);
         d.push_front(42);
@@ -822,11 +823,11 @@ mod tests {
         e.push_back(17);
         e.push_back(137);
         e.push_back(137);
-        assert_eq!(&e, &d);
+        assert!(&e == &d);
         e.pop_back();
         e.push_back(0);
         assert!(e != d);
         e.clear();
-        assert_eq!(e, RingBuf::new());
+        assert!(e == RingBuf::new());
     }
 }

src/libgetopts/lib.rs

@@ -1361,7 +1361,7 @@ mod tests {
                                 aliases: ~[] }];
         let verbose = reqopt("b", "banana", "some bananas", "VAL");
 
-        assert_eq!(verbose.long_to_short(), short);
+        assert!(verbose.long_to_short() == short);
     }
 
     #[test]

src/libnum/bigint.rs

@@ -829,7 +829,7 @@ fn get_radix_base(radix: uint) -> (uint, uint) {
 }
 
 /// A Sign is a `BigInt`'s composing element.
-#[deriving(Eq, Clone)]
+#[deriving(Eq, Clone, Show)]
 pub enum Sign { Minus, Zero, Plus }
 
 impl Ord for Sign {

src/librustc/back/rpath.rs

@@ -215,7 +215,7 @@ mod test {
     #[test]
     fn test_minimize1() {
         let res = minimize_rpaths([~"rpath1", ~"rpath2", ~"rpath1"]);
-        assert_eq!(res.as_slice(), [~"rpath1", ~"rpath2"]);
+        assert!(res.as_slice() == [~"rpath1", ~"rpath2"]);
     }
 
     #[test]
@@ -224,7 +224,7 @@ mod test {
                                    ~"1a", ~"4a", ~"1a",
                                    ~"2",  ~"3",  ~"4a",
                                    ~"3"]);
-        assert_eq!(res.as_slice(), [~"1a", ~"2", ~"4a", ~"3"]);
+        assert!(res.as_slice() == [~"1a", ~"2", ~"4a", ~"3"]);
     }
 
     #[test]

src/librustc/middle/astencode.rs

@@ -1468,7 +1468,7 @@ fn roundtrip(in_item: Option<@ast::Item>) {
     let ebml_doc = reader::Doc(wr.get_ref());
     let out_item = decode_item_ast(ebml_doc);
 
-    assert_eq!(in_item, out_item);
+    assert!(in_item == out_item);
 }
 
 #[test]

src/librustc/middle/graph.rs

@@ -349,19 +349,19 @@ mod test {
                                       start_data: N,
                                       expected_incoming: &[(E,N)],
                                       expected_outgoing: &[(E,N)]) {
-        assert_eq!(graph.node_data(start_index), &start_data);
+        assert!(graph.node_data(start_index) == &start_data);
 
         let mut counter = 0;
         graph.each_incoming_edge(start_index, |edge_index, edge| {
-            assert_eq!(graph.edge_data(edge_index), &edge.data);
+            assert!(graph.edge_data(edge_index) == &edge.data);
             assert!(counter < expected_incoming.len());
             debug!("counter={:?} expected={:?} edge_index={:?} edge={:?}",
                    counter, expected_incoming[counter], edge_index, edge);
             match expected_incoming[counter] {
                 (ref e, ref n) => {
-                    assert_eq!(e, &edge.data);
-                    assert_eq!(n, graph.node_data(edge.source));
-                    assert_eq!(start_index, edge.target);
+                    assert!(e == &edge.data);
+                    assert!(n == graph.node_data(edge.source));
+                    assert!(start_index == edge.target);
                 }
             }
             counter += 1;
@@ -371,15 +371,15 @@ mod test {
 
         let mut counter = 0;
         graph.each_outgoing_edge(start_index, |edge_index, edge| {
-            assert_eq!(graph.edge_data(edge_index), &edge.data);
+            assert!(graph.edge_data(edge_index) == &edge.data);
             assert!(counter < expected_outgoing.len());
             debug!("counter={:?} expected={:?} edge_index={:?} edge={:?}",
                    counter, expected_outgoing[counter], edge_index, edge);
             match expected_outgoing[counter] {
                 (ref e, ref n) => {
-                    assert_eq!(e, &edge.data);
-                    assert_eq!(start_index, edge.source);
-                    assert_eq!(n, graph.node_data(edge.target));
+                    assert!(e == &edge.data);
+                    assert!(start_index == edge.source);
+                    assert!(n == graph.node_data(edge.target));
                 }
             }
             counter += 1;

src/librustc/middle/trans/type_.rs

@@ -25,7 +25,7 @@ use std::cast;
 
 use std::libc::{c_uint};
 
-#[deriving(Clone, Eq)]
+#[deriving(Clone, Eq, Show)]
 pub struct Type {
     priv rf: TypeRef
 }

src/librustc/middle/typeck/infer/region_inference/mod.rs

@@ -761,7 +761,7 @@ impl RegionVarBindings {
 
 // ______________________________________________________________________
 
-#[deriving(Eq)]
+#[deriving(Eq, Show)]
 enum Classification { Expanding, Contracting }
 
 enum VarValue { NoValue, Value(Region), ErrorValue }

src/libserialize/json.rs

@@ -1588,20 +1588,20 @@ mod tests {
     use std::io;
     use collections::TreeMap;
 
-    #[deriving(Eq, Encodable, Decodable)]
+    #[deriving(Eq, Encodable, Decodable, Show)]
     enum Animal {
         Dog,
         Frog(~str, int)
     }
 
-    #[deriving(Eq, Encodable, Decodable)]
+    #[deriving(Eq, Encodable, Decodable, Show)]
     struct Inner {
         a: (),
         b: uint,
         c: ~[~str],
     }
 
-    #[deriving(Eq, Encodable, Decodable)]
+    #[deriving(Eq, Encodable, Decodable, Show)]
     struct Outer {
         inner: ~[Inner],
     }

src/libstd/any.rs

@@ -167,7 +167,7 @@ mod tests {
     use prelude::*;
     use super::*;
 
-    #[deriving(Eq)]
+    #[deriving(Eq, Show)]
     struct Test;
 
     static TEST: &'static str = "Test";

src/libstd/ascii.rs

@@ -475,7 +475,7 @@ mod tests {
     use char::from_u32;
 
     macro_rules! v2ascii (
-        ( [$($e:expr),*]) => ( [$(Ascii{chr:$e}),*]);
+        ( [$($e:expr),*]) => (&[$(Ascii{chr:$e}),*]);
         (&[$($e:expr),*]) => (&[$(Ascii{chr:$e}),*]);
         (~[$($e:expr),*]) => (~[$(Ascii{chr:$e}),*]);
     )

src/libstd/bool.rs

@@ -293,9 +293,9 @@ mod tests {
 
     #[test]
     fn test_totalord() {
-        assert_eq!(true.cmp(&true), Equal);
-        assert_eq!(false.cmp(&false), Equal);
-        assert_eq!(true.cmp(&false), Greater);
-        assert_eq!(false.cmp(&true), Less);
+        assert!(true.cmp(&true) == Equal);
+        assert!(false.cmp(&false) == Equal);
+        assert!(true.cmp(&false) == Greater);
+        assert!(false.cmp(&true) == Less);
     }
 }

src/libstd/cell.rs

@@ -10,12 +10,13 @@
 
 //! Types dealing with dynamic mutability
 
+use cast;
 use clone::{Clone, DeepClone};
 use cmp::Eq;
+use fmt;
+use kinds::{marker, Pod};
 use ops::Drop;
 use option::{None, Option, Some};
-use cast;
-use kinds::{marker, Pod};
 
 /// A mutable memory location that admits only `Pod` data.
 pub struct Cell<T> {
@@ -61,6 +62,12 @@ impl<T:Eq + Pod> Eq for Cell<T> {
     }
 }
 
+impl<T: fmt::Show> fmt::Show for Cell<T> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f.buf, r"Cell \{ value: {} \}", self.value)
+    }
+}
+
 /// A mutable memory location with dynamically checked borrow rules
 pub struct RefCell<T> {
     priv value: T,

src/libstd/cmp.rs

@@ -72,7 +72,7 @@ totaleq_impl!(uint)
 
 totaleq_impl!(char)
 
-#[deriving(Clone, Eq)]
+#[deriving(Clone, Eq, Show)]
 pub enum Ordering { Less = -1, Equal = 0, Greater = 1 }
 
 /// Trait for types that form a total order

src/libstd/comm/mod.rs

@@ -313,7 +313,7 @@ pub struct Chan<T> {
 
 /// This enumeration is the list of the possible reasons that try_recv could not
 /// return data when called.
-#[deriving(Eq, Clone)]
+#[deriving(Eq, Clone, Show)]
 pub enum TryRecvResult<T> {
     /// This channel is currently empty, but the sender(s) have not yet
     /// disconnected, so data may yet become available.