Auto merge of #44709 - Badel2:inclusive-range-dotdoteq, r=petrochenkov

Initial support for `..=` syntax

#28237

This PR adds `..=` as a synonym for `...` in patterns and expressions.
Since `...` in expressions was never stable, we now issue a warning.

cc @durka
r? @aturon

Author: bors

src/Cargo.lock

@@ -7,13 +7,13 @@ The tracking issue for this feature is: [#28237]
 ------------------------
 
 To get a range that goes from 0 to 10 and includes the value 10, you
-can write `0...10`:
+can write `0..=10`:
 
 ```rust
 #![feature(inclusive_range_syntax)]
 
 fn main() {
-    for i in 0...10 {
+    for i in 0..=10 {
         println!("{}", i);
     }
 }

src/doc/unstable-book/src/language-features/inclusive-range-syntax.md

@@ -182,7 +182,7 @@ fn test_range_small() {
 fn test_range_inclusive() {
     let size = 500;
 
-    let map: BTreeMap<_, _> = (0...size).map(|i| (i, i)).collect();
+    let map: BTreeMap<_, _> = (0..=size).map(|i| (i, i)).collect();
 
     fn check<'a, L, R>(lhs: L, rhs: R)
         where L: IntoIterator<Item=(&'a i32, &'a i32)>,
@@ -193,26 +193,26 @@ fn test_range_inclusive() {
         assert_eq!(lhs, rhs);
     }
 
-    check(map.range(size + 1...size + 1), vec![]);
-    check(map.range(size...size), vec![(&size, &size)]);
-    check(map.range(size...size + 1), vec![(&size, &size)]);
-    check(map.range(0...0), vec![(&0, &0)]);
-    check(map.range(0...size - 1), map.range(..size));
-    check(map.range(-1...-1), vec![]);
-    check(map.range(-1...size), map.range(..));
-    check(map.range(...size), map.range(..));
-    check(map.range(...200), map.range(..201));
-    check(map.range(5...8), vec![(&5, &5), (&6, &6), (&7, &7), (&8, &8)]);
-    check(map.range(-1...0), vec![(&0, &0)]);
-    check(map.range(-1...2), vec![(&0, &0), (&1, &1), (&2, &2)]);
+    check(map.range(size + 1..=size + 1), vec![]);
+    check(map.range(size..=size), vec![(&size, &size)]);
+    check(map.range(size..=size + 1), vec![(&size, &size)]);
+    check(map.range(0..=0), vec![(&0, &0)]);
+    check(map.range(0..=size - 1), map.range(..size));
+    check(map.range(-1..=-1), vec![]);
+    check(map.range(-1..=size), map.range(..));
+    check(map.range(..=size), map.range(..));
+    check(map.range(..=200), map.range(..201));
+    check(map.range(5..=8), vec![(&5, &5), (&6, &6), (&7, &7), (&8, &8)]);
+    check(map.range(-1..=0), vec![(&0, &0)]);
+    check(map.range(-1..=2), vec![(&0, &0), (&1, &1), (&2, &2)]);
 }
 
 #[test]
 fn test_range_inclusive_max_value() {
     let max = ::std::usize::MAX;
     let map: BTreeMap<_, _> = vec![(max, 0)].into_iter().collect();
 
-    assert_eq!(map.range(max...max).collect::<Vec<_>>(), &[(&max, &0)]);
+    assert_eq!(map.range(max..=max).collect::<Vec<_>>(), &[(&max, &0)]);
 }
 
 #[test]

src/liballoc/tests/btree/map.rs

@@ -361,43 +361,43 @@ fn test_slice_fail() {
 #[test]
 #[should_panic]
 fn test_str_slice_rangetoinclusive_max_panics() {
-    &"hello"[...usize::max_value()];
+    &"hello"[..=usize::max_value()];
 }
 
 #[test]
 #[should_panic]
 fn test_str_slice_rangeinclusive_max_panics() {
-    &"hello"[1...usize::max_value()];
+    &"hello"[1..=usize::max_value()];
 }
 
 #[test]
 #[should_panic]
 fn test_str_slicemut_rangetoinclusive_max_panics() {
     let mut s = "hello".to_owned();
     let s: &mut str = &mut s;
-    &mut s[...usize::max_value()];
+    &mut s[..=usize::max_value()];
 }
 
 #[test]
 #[should_panic]
 fn test_str_slicemut_rangeinclusive_max_panics() {
     let mut s = "hello".to_owned();
     let s: &mut str = &mut s;
-    &mut s[1...usize::max_value()];
+    &mut s[1..=usize::max_value()];
 }
 
 #[test]
 fn test_str_get_maxinclusive() {
     let mut s = "hello".to_owned();
     {
         let s: &str = &s;
-        assert_eq!(s.get(...usize::max_value()), None);
-        assert_eq!(s.get(1...usize::max_value()), None);
+        assert_eq!(s.get(..=usize::max_value()), None);
+        assert_eq!(s.get(1..=usize::max_value()), None);
     }
     {
         let s: &mut str = &mut s;
-        assert_eq!(s.get(...usize::max_value()), None);
-        assert_eq!(s.get(1...usize::max_value()), None);
+        assert_eq!(s.get(..=usize::max_value()), None);
+        assert_eq!(s.get(1..=usize::max_value()), None);
     }
 }
 

src/liballoc/tests/str.rs

@@ -456,9 +456,9 @@ fn test_splice_char_boundary() {
 #[test]
 fn test_splice_inclusive_range() {
     let mut v = String::from("12345");
-    v.splice(2...3, "789");
+    v.splice(2..=3, "789");
     assert_eq!(v, "127895");
-    v.splice(1...2, "A");
+    v.splice(1..=2, "A");
     assert_eq!(v, "1A895");
 }
 
@@ -473,7 +473,7 @@ fn test_splice_out_of_bounds() {
 #[should_panic]
 fn test_splice_inclusive_out_of_bounds() {
     let mut s = String::from("12345");
-    s.splice(5...5, "789");
+    s.splice(5..=5, "789");
 }
 
 #[test]

src/liballoc/tests/string.rs

@@ -537,27 +537,27 @@ fn test_drain_range() {
 #[test]
 fn test_drain_inclusive_range() {
     let mut v = vec!['a', 'b', 'c', 'd', 'e'];
-    for _ in v.drain(1...3) {
+    for _ in v.drain(1..=3) {
     }
     assert_eq!(v, &['a', 'e']);
 
-    let mut v: Vec<_> = (0...5).map(|x| x.to_string()).collect();
-    for _ in v.drain(1...5) {
+    let mut v: Vec<_> = (0..=5).map(|x| x.to_string()).collect();
+    for _ in v.drain(1..=5) {
     }
     assert_eq!(v, &["0".to_string()]);
 
-    let mut v: Vec<String> = (0...5).map(|x| x.to_string()).collect();
-    for _ in v.drain(0...5) {
+    let mut v: Vec<String> = (0..=5).map(|x| x.to_string()).collect();
+    for _ in v.drain(0..=5) {
     }
     assert_eq!(v, Vec::<String>::new());
 
-    let mut v: Vec<_> = (0...5).map(|x| x.to_string()).collect();
-    for _ in v.drain(0...3) {
+    let mut v: Vec<_> = (0..=5).map(|x| x.to_string()).collect();
+    for _ in v.drain(0..=3) {
     }
     assert_eq!(v, &["4".to_string(), "5".to_string()]);
 
-    let mut v: Vec<_> = (0...1).map(|x| x.to_string()).collect();
-    for _ in v.drain(...0) {
+    let mut v: Vec<_> = (0..=1).map(|x| x.to_string()).collect();
+    for _ in v.drain(..=0) {
     }
     assert_eq!(v, &["1".to_string()]);
 }
@@ -572,7 +572,7 @@ fn test_drain_max_vec_size() {
 
     let mut v = Vec::<()>::with_capacity(usize::max_value());
     unsafe { v.set_len(usize::max_value()); }
-    for _ in v.drain(usize::max_value() - 1...usize::max_value() - 1) {
+    for _ in v.drain(usize::max_value() - 1..=usize::max_value() - 1) {
     }
     assert_eq!(v.len(), usize::max_value() - 1);
 }
@@ -581,7 +581,7 @@ fn test_drain_max_vec_size() {
 #[should_panic]
 fn test_drain_inclusive_out_of_bounds() {
     let mut v = vec![1, 2, 3, 4, 5];
-    v.drain(5...5);
+    v.drain(5..=5);
 }
 
 #[test]
@@ -598,10 +598,10 @@ fn test_splice() {
 fn test_splice_inclusive_range() {
     let mut v = vec![1, 2, 3, 4, 5];
     let a = [10, 11, 12];
-    let t1: Vec<_> = v.splice(2...3, a.iter().cloned()).collect();
+    let t1: Vec<_> = v.splice(2..=3, a.iter().cloned()).collect();
     assert_eq!(v, &[1, 2, 10, 11, 12, 5]);
     assert_eq!(t1, &[3, 4]);
-    let t2: Vec<_> = v.splice(1...2, Some(20)).collect();
+    let t2: Vec<_> = v.splice(1..=2, Some(20)).collect();
     assert_eq!(v, &[1, 20, 11, 12, 5]);
     assert_eq!(t2, &[2, 10]);
 }
@@ -619,7 +619,7 @@ fn test_splice_out_of_bounds() {
 fn test_splice_inclusive_out_of_bounds() {
     let mut v = vec![1, 2, 3, 4, 5];
     let a = [10, 11, 12];
-    v.splice(5...5, a.iter().cloned());
+    v.splice(5..=5, a.iter().cloned());
 }
 
 #[test]

src/liballoc/tests/vec.rs

@@ -241,22 +241,22 @@ impl<Idx: PartialOrd<Idx>> RangeTo<Idx> {
     }
 }
 
-/// An range bounded inclusively below and above (`start...end`).
+/// An range bounded inclusively below and above (`start..=end`).
 ///
-/// The `RangeInclusive` `start...end` contains all values with `x >= start`
+/// The `RangeInclusive` `start..=end` contains all values with `x >= start`
 /// and `x <= end`.
 ///
 /// # Examples
 ///
 /// ```
 /// #![feature(inclusive_range,inclusive_range_syntax)]
 ///
-/// assert_eq!((3...5), std::ops::RangeInclusive { start: 3, end: 5 });
-/// assert_eq!(3 + 4 + 5, (3...5).sum());
+/// assert_eq!((3..=5), std::ops::RangeInclusive { start: 3, end: 5 });
+/// assert_eq!(3 + 4 + 5, (3..=5).sum());
 ///
 /// let arr = [0, 1, 2, 3];
-/// assert_eq!(arr[ ...2], [0,1,2  ]);
-/// assert_eq!(arr[1...2], [  1,2  ]);  // RangeInclusive
+/// assert_eq!(arr[ ..=2], [0,1,2  ]);
+/// assert_eq!(arr[1..=2], [  1,2  ]);  // RangeInclusive
 /// ```
 #[derive(Clone, PartialEq, Eq, Hash)]  // not Copy -- see #27186
 #[unstable(feature = "inclusive_range", reason = "recently added, follows RFC", issue = "28237")]
@@ -276,7 +276,7 @@ pub struct RangeInclusive<Idx> {
 #[unstable(feature = "inclusive_range", reason = "recently added, follows RFC", issue = "28237")]
 impl<Idx: fmt::Debug> fmt::Debug for RangeInclusive<Idx> {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        write!(fmt, "{:?}...{:?}", self.start, self.end)
+        write!(fmt, "{:?}..={:?}", self.start, self.end)
     }
 }
 
@@ -289,32 +289,32 @@ impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
     /// ```
     /// #![feature(range_contains,inclusive_range_syntax)]
     ///
-    /// assert!(!(3...5).contains(2));
-    /// assert!( (3...5).contains(3));
-    /// assert!( (3...5).contains(4));
-    /// assert!( (3...5).contains(5));
-    /// assert!(!(3...5).contains(6));
+    /// assert!(!(3..=5).contains(2));
+    /// assert!( (3..=5).contains(3));
+    /// assert!( (3..=5).contains(4));
+    /// assert!( (3..=5).contains(5));
+    /// assert!(!(3..=5).contains(6));
     ///
-    /// assert!( (3...3).contains(3));
-    /// assert!(!(3...2).contains(3));
+    /// assert!( (3..=3).contains(3));
+    /// assert!(!(3..=2).contains(3));
     /// ```
     pub fn contains(&self, item: Idx) -> bool {
         self.start <= item && item <= self.end
     }
 }
 
-/// A range only bounded inclusively above (`...end`).
+/// A range only bounded inclusively above (`..=end`).
 ///
-/// The `RangeToInclusive` `...end` contains all values with `x <= end`.
+/// The `RangeToInclusive` `..=end` contains all values with `x <= end`.
 /// It cannot serve as an [`Iterator`] because it doesn't have a starting point.
 ///
 /// # Examples
 ///
-/// The `...end` syntax is a `RangeToInclusive`:
+/// The `..=end` syntax is a `RangeToInclusive`:
 ///
 /// ```
 /// #![feature(inclusive_range,inclusive_range_syntax)]
-/// assert_eq!((...5), std::ops::RangeToInclusive{ end: 5 });
+/// assert_eq!((..=5), std::ops::RangeToInclusive{ end: 5 });
 /// ```
 ///
 /// It does not have an [`IntoIterator`] implementation, so you can't use it in a
@@ -325,7 +325,7 @@ impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
 ///
 /// // error[E0277]: the trait bound `std::ops::RangeToInclusive<{integer}>:
 /// // std::iter::Iterator` is not satisfied
-/// for i in ...5 {
+/// for i in ..=5 {
 ///     // ...
 /// }
 /// ```
@@ -337,8 +337,8 @@ impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
 /// #![feature(inclusive_range_syntax)]
 ///
 /// let arr = [0, 1, 2, 3];
-/// assert_eq!(arr[ ...2], [0,1,2  ]);  // RangeToInclusive
-/// assert_eq!(arr[1...2], [  1,2  ]);
+/// assert_eq!(arr[ ..=2], [0,1,2  ]);  // RangeToInclusive
+/// assert_eq!(arr[1..=2], [  1,2  ]);
 /// ```
 ///
 /// [`IntoIterator`]: ../iter/trait.Iterator.html
@@ -357,7 +357,7 @@ pub struct RangeToInclusive<Idx> {
 #[unstable(feature = "inclusive_range", reason = "recently added, follows RFC", issue = "28237")]
 impl<Idx: fmt::Debug> fmt::Debug for RangeToInclusive<Idx> {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        write!(fmt, "...{:?}", self.end)
+        write!(fmt, "..={:?}", self.end)
     }
 }
 
@@ -370,9 +370,9 @@ impl<Idx: PartialOrd<Idx>> RangeToInclusive<Idx> {
     /// ```
     /// #![feature(range_contains,inclusive_range_syntax)]
     ///
-    /// assert!( (...5).contains(-1_000_000_000));
-    /// assert!( (...5).contains(5));
-    /// assert!(!(...5).contains(6));
+    /// assert!( (..=5).contains(-1_000_000_000));
+    /// assert!( (..=5).contains(5));
+    /// assert!(!(..=5).contains(6));
     /// ```
     pub fn contains(&self, item: Idx) -> bool {
         (item <= self.end)