Rollup merge of #60931 - cuviper:array-iter, r=KodrAus

Use iter() for iterating arrays by slice

These `into_iter()` calls will change from iterating references to
values if we ever get `IntoIterator` for arrays, which may break the
code using that iterator. Calling `iter()` is future proof.

src/liballoc/tests/btree/set.rs

@@ -143,8 +143,8 @@ fn check_union(a: &[i32], b: &[i32], expected: &[i32]) {
 #[test]
 // Only tests the simple function definition with respect to intersection
 fn test_is_disjoint() {
-    let one = [1].into_iter().collect::<BTreeSet<_>>();
-    let two = [2].into_iter().collect::<BTreeSet<_>>();
+    let one = [1].iter().collect::<BTreeSet<_>>();
+    let two = [2].iter().collect::<BTreeSet<_>>();
     assert!(one.is_disjoint(&two));
 }
 

src/libcore/iter/traits/iterator.rs

@@ -356,7 +356,7 @@ fn nth(&mut self, mut n: usize) -> Option<Self::Item> {
     ///
     /// ```
     /// let a = [0, 1, 2, 3, 4, 5];
-    /// let mut iter = a.into_iter().step_by(2);
+    /// let mut iter = a.iter().step_by(2);
     ///
     /// assert_eq!(iter.next(), Some(&0));
     /// assert_eq!(iter.next(), Some(&2));
@@ -531,7 +531,7 @@ fn zip<U>(self, other: U) -> Zip<Self, U::IntoIter> where
     /// ```
     /// let a = [1, 2, 3];
     ///
-    /// let mut iter = a.into_iter().map(|x| 2 * x);
+    /// let mut iter = a.iter().map(|x| 2 * x);
     ///
     /// assert_eq!(iter.next(), Some(2));
     /// assert_eq!(iter.next(), Some(4));
@@ -620,7 +620,7 @@ fn for_each<F>(self, mut f: F) where
     /// ```
     /// let a = [0i32, 1, 2];
     ///
-    /// let mut iter = a.into_iter().filter(|x| x.is_positive());
+    /// let mut iter = a.iter().filter(|x| x.is_positive());
     ///
     /// assert_eq!(iter.next(), Some(&1));
     /// assert_eq!(iter.next(), Some(&2));
@@ -634,7 +634,7 @@ fn for_each<F>(self, mut f: F) where
     /// ```
     /// let a = [0, 1, 2];
     ///
-    /// let mut iter = a.into_iter().filter(|x| **x > 1); // need two *s!
+    /// let mut iter = a.iter().filter(|x| **x > 1); // need two *s!
     ///
     /// assert_eq!(iter.next(), Some(&2));
     /// assert_eq!(iter.next(), None);
@@ -646,7 +646,7 @@ fn for_each<F>(self, mut f: F) where
     /// ```
     /// let a = [0, 1, 2];
     ///
-    /// let mut iter = a.into_iter().filter(|&x| *x > 1); // both & and *
+    /// let mut iter = a.iter().filter(|&x| *x > 1); // both & and *
     ///
     /// assert_eq!(iter.next(), Some(&2));
     /// assert_eq!(iter.next(), None);
@@ -657,7 +657,7 @@ fn for_each<F>(self, mut f: F) where
     /// ```
     /// let a = [0, 1, 2];
     ///
-    /// let mut iter = a.into_iter().filter(|&&x| x > 1); // two &s
+    /// let mut iter = a.iter().filter(|&&x| x > 1); // two &s
     ///
     /// assert_eq!(iter.next(), Some(&2));
     /// assert_eq!(iter.next(), None);
@@ -837,7 +837,7 @@ fn peekable(self) -> Peekable<Self> where Self: Sized {
     /// ```
     /// let a = [-1i32, 0, 1];
     ///
-    /// let mut iter = a.into_iter().skip_while(|x| x.is_negative());
+    /// let mut iter = a.iter().skip_while(|x| x.is_negative());
     ///
     /// assert_eq!(iter.next(), Some(&0));
     /// assert_eq!(iter.next(), Some(&1));
@@ -851,7 +851,7 @@ fn peekable(self) -> Peekable<Self> where Self: Sized {
     /// ```
     /// let a = [-1, 0, 1];
     ///
-    /// let mut iter = a.into_iter().skip_while(|x| **x < 0); // need two *s!
+    /// let mut iter = a.iter().skip_while(|x| **x < 0); // need two *s!
     ///
     /// assert_eq!(iter.next(), Some(&0));
     /// assert_eq!(iter.next(), Some(&1));
@@ -863,7 +863,7 @@ fn peekable(self) -> Peekable<Self> where Self: Sized {
     /// ```
     /// let a = [-1, 0, 1, -2];
     ///
-    /// let mut iter = a.into_iter().skip_while(|x| **x < 0);
+    /// let mut iter = a.iter().skip_while(|x| **x < 0);
     ///
     /// assert_eq!(iter.next(), Some(&0));
     /// assert_eq!(iter.next(), Some(&1));
@@ -898,7 +898,7 @@ fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
     /// ```
     /// let a = [-1i32, 0, 1];
     ///
-    /// let mut iter = a.into_iter().take_while(|x| x.is_negative());
+    /// let mut iter = a.iter().take_while(|x| x.is_negative());
     ///
     /// assert_eq!(iter.next(), Some(&-1));
     /// assert_eq!(iter.next(), None);
@@ -911,7 +911,7 @@ fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
     /// ```
     /// let a = [-1, 0, 1];
     ///
-    /// let mut iter = a.into_iter().take_while(|x| **x < 0); // need two *s!
+    /// let mut iter = a.iter().take_while(|x| **x < 0); // need two *s!
     ///
     /// assert_eq!(iter.next(), Some(&-1));
     /// assert_eq!(iter.next(), None);
@@ -922,7 +922,7 @@ fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
     /// ```
     /// let a = [-1, 0, 1, -2];
     ///
-    /// let mut iter = a.into_iter().take_while(|x| **x < 0);
+    /// let mut iter = a.iter().take_while(|x| **x < 0);
     ///
     /// assert_eq!(iter.next(), Some(&-1));
     ///
@@ -937,7 +937,7 @@ fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
     ///
     /// ```
     /// let a = [1, 2, 3, 4];
-    /// let mut iter = a.into_iter();
+    /// let mut iter = a.iter();
     ///
     /// let result: Vec<i32> = iter.by_ref()
     ///                            .take_while(|n| **n != 3)
@@ -1321,7 +1321,7 @@ fn inspect<F>(self, f: F) -> Inspect<Self, F> where
     /// ```
     /// let a = [1, 2, 3];
     ///
-    /// let iter = a.into_iter();
+    /// let iter = a.iter();
     ///
     /// let sum: i32 = iter.take(5).fold(0, |acc, i| acc + i );
     ///
@@ -1334,7 +1334,7 @@ fn inspect<F>(self, f: F) -> Inspect<Self, F> where
     /// // let's try that again
     /// let a = [1, 2, 3];
     ///
-    /// let mut iter = a.into_iter();
+    /// let mut iter = a.iter();
     ///
     /// // instead, we add in a .by_ref()
     /// let sum: i32 = iter.by_ref().take(2).fold(0, |acc, i| acc + i );
@@ -1479,7 +1479,7 @@ fn collect<B: FromIterator<Self::Item>>(self) -> B where Self: Sized {
     /// let a = [1, 2, 3];
     ///
     /// let (even, odd): (Vec<i32>, Vec<i32>) = a
-    ///     .into_iter()
+    ///     .iter()
     ///     .partition(|&n| n % 2 == 0);
     ///
     /// assert_eq!(even, vec![2]);

src/librustdoc/config.rs

@@ -538,7 +538,7 @@ fn check_deprecated_options(matches: &getopts::Matches, diag: &errors::Handler)
        "passes",
     ];
 
-    for flag in deprecated_flags.into_iter() {
+    for flag in deprecated_flags.iter() {
         if matches.opt_present(flag) {
             let mut err = diag.struct_warn(&format!("the '{}' flag is considered deprecated",
                                                     flag));

src/librustdoc/html/render.rs

@@ -506,7 +506,7 @@ pub fn initial_ids() -> Vec<String> {
      "methods",
      "deref-methods",
      "implementations",
-    ].into_iter().map(|id| (String::from(*id))).collect()
+    ].iter().map(|id| (String::from(*id))).collect()
 }
 
 /// Generates the documentation for `crate` into the directory `dst`