Auto merge of #28052 - Manishearth:rollup, r=Manishearth

- Successful merges: #28010, #28013, #28022, #28029, #28033, #28039, #28045, #28048
- Failed merges:

Author: bors

Diff for: src/doc/trpl/testing.md

@@ -120,13 +120,26 @@ And that's reflected in the summary line:
 test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured
 ```
 
-We also get a non-zero status code:
+We also get a non-zero status code. We can use `$?` on OS X and Linux:
 
 ```bash
 $ echo $?
 101
 ```
 
+On Windows, if you’re using `cmd`:
+
+```bash
+> echo %ERRORLEVEL%
+```
+
+And if you’re using PowerShell:
+
+```bash
+> echo $LASTEXITCODE # the code itself
+> echo $? # a boolean, fail or succeed
+```
+
 This is useful if you want to integrate `cargo test` into other tooling.
 
 We can invert our test's failure with another attribute: `should_panic`:

Diff for: src/libcore/macros.rs

@@ -254,6 +254,51 @@ macro_rules! unreachable {
 
 /// A standardised placeholder for marking unfinished code. It panics with the
 /// message `"not yet implemented"` when executed.
+///
+/// This can be useful if you are prototyping and are just looking to have your
+/// code typecheck, or if you're implementing a trait that requires multiple
+/// methods, and you're only planning on using one of them.
+///
+/// # Examples
+///
+/// Here's an example of some in-progress code. We have a trait `Foo`:
+///
+/// ```
+/// trait Foo {
+///     fn bar(&self);
+///     fn baz(&self);
+/// }
+/// ```
+///
+/// We want to implement `Foo` on one of our types, but we also want to work on
+/// just `bar()` first. In order for our code to compile, we need to implement
+/// `baz()`, so we can use `unimplemented!`:
+///
+/// ```
+/// # trait Foo {
+/// #     fn foo(&self);
+/// #     fn bar(&self);
+/// # }
+/// struct MyStruct;
+///
+/// impl Foo for MyStruct {
+///     fn foo(&self) {
+///         // implementation goes here
+///     }
+///
+///     fn bar(&self) {
+///         // let's not worry about implementing bar() for now
+///         unimplemented!();
+///     }
+/// }
+///
+/// fn main() {
+///     let s = MyStruct;
+///     s.foo();
+///
+///     // we aren't even using bar() yet, so this is fine.
+/// }
+/// ```
 #[macro_export]
 #[unstable(feature = "core",
            reason = "relationship with panic is unclear")]

Diff for: src/libcore/option.rs

@@ -779,6 +779,26 @@ impl<T> IntoIterator for Option<T> {
     }
 }
 
+#[stable(since = "1.4.0", feature = "option_iter")]
+impl<'a, T> IntoIterator for &'a Option<T> {
+    type Item = &'a T;
+    type IntoIter = Iter<'a, T>;
+
+    fn into_iter(self) -> Iter<'a, T> {
+        self.iter()
+    }
+}
+
+#[stable(since = "1.4.0", feature = "option_iter")]
+impl<'a, T> IntoIterator for &'a mut Option<T> {
+    type Item = &'a mut T;
+    type IntoIter = IterMut<'a, T>;
+
+    fn into_iter(mut self) -> IterMut<'a, T> {
+        self.iter_mut()
+    }
+}
+
 /////////////////////////////////////////////////////////////////////////////
 // The Option Iterators
 /////////////////////////////////////////////////////////////////////////////

Diff for: src/libcore/result.rs

@@ -815,6 +815,26 @@ impl<T, E> IntoIterator for Result<T, E> {
     }
 }
 
+#[stable(since = "1.4.0", feature = "result_iter")]
+impl<'a, T, E> IntoIterator for &'a Result<T, E> {
+    type Item = &'a T;
+    type IntoIter = Iter<'a, T>;
+
+    fn into_iter(self) -> Iter<'a, T> {
+        self.iter()
+    }
+}
+
+#[stable(since = "1.4.0", feature = "result_iter")]
+impl<'a, T, E> IntoIterator for &'a mut Result<T, E> {
+    type Item = &'a mut T;
+    type IntoIter = IterMut<'a, T>;
+
+    fn into_iter(mut self) -> IterMut<'a, T> {
+        self.iter_mut()
+    }
+}
+
 /////////////////////////////////////////////////////////////////////////////
 // The Result Iterators
 /////////////////////////////////////////////////////////////////////////////

Diff for: src/libcoretest/iter.rs

@@ -9,7 +9,6 @@
 // except according to those terms.
 
 use core::iter::*;
-use core::iter::order::*;
 use core::{i8, i16, isize};
 use core::usize;
 
@@ -21,51 +20,51 @@ fn test_lt() {
     let xs = [1,2,3];
     let ys = [1,2,0];
 
-    assert!(!lt(xs.iter(), ys.iter()));
-    assert!(!le(xs.iter(), ys.iter()));
-    assert!( gt(xs.iter(), ys.iter()));
-    assert!( ge(xs.iter(), ys.iter()));
+    assert!(!xs.iter().lt(ys.iter()));
+    assert!(!xs.iter().le(ys.iter()));
+    assert!( xs.iter().gt(ys.iter()));
+    assert!( xs.iter().ge(ys.iter()));
 
-    assert!( lt(ys.iter(), xs.iter()));
-    assert!( le(ys.iter(), xs.iter()));
-    assert!(!gt(ys.iter(), xs.iter()));
-    assert!(!ge(ys.iter(), xs.iter()));
+    assert!( ys.iter().lt(xs.iter()));
+    assert!( ys.iter().le(xs.iter()));
+    assert!(!ys.iter().gt(xs.iter()));
+    assert!(!ys.iter().ge(xs.iter()));
 
-    assert!( lt(empty.iter(), xs.iter()));
-    assert!( le(empty.iter(), xs.iter()));
-    assert!(!gt(empty.iter(), xs.iter()));
-    assert!(!ge(empty.iter(), xs.iter()));
+    assert!( empty.iter().lt(xs.iter()));
+    assert!( empty.iter().le(xs.iter()));
+    assert!(!empty.iter().gt(xs.iter()));
+    assert!(!empty.iter().ge(xs.iter()));
 
     // Sequence with NaN
     let u = [1.0f64, 2.0];
     let v = [0.0f64/0.0, 3.0];
 
-    assert!(!lt(u.iter(), v.iter()));
-    assert!(!le(u.iter(), v.iter()));
-    assert!(!gt(u.iter(), v.iter()));
-    assert!(!ge(u.iter(), v.iter()));
+    assert!(!u.iter().lt(v.iter()));
+    assert!(!u.iter().le(v.iter()));
+    assert!(!u.iter().gt(v.iter()));
+    assert!(!u.iter().ge(v.iter()));
 
     let a = [0.0f64/0.0];
     let b = [1.0f64];
     let c = [2.0f64];
 
-    assert!(lt(a.iter(), b.iter()) == (a[0] <  b[0]));
-    assert!(le(a.iter(), b.iter()) == (a[0] <= b[0]));
-    assert!(gt(a.iter(), b.iter()) == (a[0] >  b[0]));
-    assert!(ge(a.iter(), b.iter()) == (a[0] >= b[0]));
+    assert!(a.iter().lt(b.iter()) == (a[0] <  b[0]));
+    assert!(a.iter().le(b.iter()) == (a[0] <= b[0]));
+    assert!(a.iter().gt(b.iter()) == (a[0] >  b[0]));
+    assert!(a.iter().ge(b.iter()) == (a[0] >= b[0]));
 
-    assert!(lt(c.iter(), b.iter()) == (c[0] <  b[0]));
-    assert!(le(c.iter(), b.iter()) == (c[0] <= b[0]));
-    assert!(gt(c.iter(), b.iter()) == (c[0] >  b[0]));
-    assert!(ge(c.iter(), b.iter()) == (c[0] >= b[0]));
+    assert!(c.iter().lt(b.iter()) == (c[0] <  b[0]));
+    assert!(c.iter().le(b.iter()) == (c[0] <= b[0]));
+    assert!(c.iter().gt(b.iter()) == (c[0] >  b[0]));
+    assert!(c.iter().ge(b.iter()) == (c[0] >= b[0]));
 }
 
 #[test]
 fn test_multi_iter() {
     let xs = [1,2,3,4];
     let ys = [4,3,2,1];
-    assert!(eq(xs.iter(), ys.iter().rev()));
-    assert!(lt(xs.iter(), xs.iter().skip(2)));
+    assert!(xs.iter().eq(ys.iter().rev()));
+    assert!(xs.iter().lt(xs.iter().skip(2)));
 }
 
 #[test]

Diff for: src/libcoretest/option.rs

@@ -180,11 +180,14 @@ fn test_iter() {
     assert_eq!(it.next(), Some(&val));
     assert_eq!(it.size_hint(), (0, Some(0)));
     assert!(it.next().is_none());
+
+    let mut it = (&x).into_iter();
+    assert_eq!(it.next(), Some(&val));
 }
 
 #[test]
 fn test_mut_iter() {
-    let val = 5;
+    let mut val = 5;
     let new_val = 11;
 
     let mut x = Some(val);
@@ -205,6 +208,10 @@ fn test_mut_iter() {
         assert!(it.next().is_none());
     }
     assert_eq!(x, Some(new_val));
+
+    let mut y = Some(val);
+    let mut it = (&mut y).into_iter();
+    assert_eq!(it.next(), Some(&mut val));
 }
 
 #[test]

Diff for: src/libcoretest/result.rs

@@ -150,3 +150,36 @@ pub fn test_expect_err() {
     let err: Result<isize, &'static str> = Err("All good");
     err.expect("Got expected error");
 }
+
+#[test]
+pub fn test_iter() {
+    let ok: Result<isize, &'static str> = Ok(100);
+    let mut it = ok.iter();
+    assert_eq!(it.size_hint(), (1, Some(1)));
+    assert_eq!(it.next(), Some(&100));
+    assert_eq!(it.size_hint(), (0, Some(0)));
+    assert!(it.next().is_none());
+    assert_eq!((&ok).into_iter().next(), Some(&100));
+
+    let err: Result<isize, &'static str> = Err("error");
+    assert_eq!(err.iter().next(), None);
+}
+
+#[test]
+pub fn test_iter_mut() {
+    let mut ok: Result<isize, &'static str> = Ok(100);
+    for loc in ok.iter_mut() {
+        *loc = 200;
+    }
+    assert_eq!(ok, Ok(200));
+    for loc in &mut ok {
+        *loc = 300;
+    }
+    assert_eq!(ok, Ok(300));
+
+    let mut err: Result<isize, &'static str> = Err("error");
+    for loc in err.iter_mut() {
+        *loc = 200;
+    }
+    assert_eq!(err, Err("error"));
+}