Rollup merge of rust-lang#136167 - pitaj:new_range, r=Nadrieril

Implement unstable `new_range` feature Switches `a..b`, `a..`, and `a..=b` to resolve to the new range types. For rust-lang/rfcs#3550 Tracking issue rust-lang#123741 also adds the re-export that was missed in the original implementation of `new_range_api`
jhpratt · Feb 4, 2025 · d31e137 · d31e137
2 parents 648fd0e + f530a29
commit d31e137
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Showing 29 changed files with 252 additions and 54 deletions.
diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs
@@ -284,9 +284,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 ExprKind::Index(el, er, brackets_span) => {
                     hir::ExprKind::Index(self.lower_expr(el), self.lower_expr(er), *brackets_span)
                 }
-                ExprKind::Range(Some(e1), Some(e2), RangeLimits::Closed) => {
-                    self.lower_expr_range_closed(e.span, e1, e2)
-                }
                 ExprKind::Range(e1, e2, lims) => {
                     self.lower_expr_range(e.span, e1.as_deref(), e2.as_deref(), *lims)
                 }
@@ -1512,15 +1509,39 @@ impl<'hir> LoweringContext<'_, 'hir> {
 
         let lang_item = match (e1, e2, lims) {
             (None, None, HalfOpen) => hir::LangItem::RangeFull,
-            (Some(..), None, HalfOpen) => hir::LangItem::RangeFrom,
+            (Some(..), None, HalfOpen) => {
+                if self.tcx.features().new_range() {
+                    hir::LangItem::RangeFromCopy
+                } else {
+                    hir::LangItem::RangeFrom
+                }
+            }
             (None, Some(..), HalfOpen) => hir::LangItem::RangeTo,
-            (Some(..), Some(..), HalfOpen) => hir::LangItem::Range,
+            (Some(..), Some(..), HalfOpen) => {
+                if self.tcx.features().new_range() {
+                    hir::LangItem::RangeCopy
+                } else {
+                    hir::LangItem::Range
+                }
+            }
             (None, Some(..), Closed) => hir::LangItem::RangeToInclusive,
-            (Some(..), Some(..), Closed) => unreachable!(),
+            (Some(e1), Some(e2), Closed) => {
+                if self.tcx.features().new_range() {
+                    hir::LangItem::RangeInclusiveCopy
+                } else {
+                    return self.lower_expr_range_closed(span, e1, e2);
+                }
+            }
             (start, None, Closed) => {
                 self.dcx().emit_err(InclusiveRangeWithNoEnd { span });
                 match start {
-                    Some(..) => hir::LangItem::RangeFrom,
+                    Some(..) => {
+                        if self.tcx.features().new_range() {
+                            hir::LangItem::RangeFromCopy
+                        } else {
+                            hir::LangItem::RangeFrom
+                        }
+                    }
                     None => hir::LangItem::RangeFull,
                 }
             }

diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs
@@ -570,6 +570,8 @@ declare_features! (
     (unstable, never_type, "1.13.0", Some(35121)),
     /// Allows diverging expressions to fall back to `!` rather than `()`.
     (unstable, never_type_fallback, "1.41.0", Some(65992)),
+    /// Switch `..` syntax to use the new (`Copy + IntoIterator`) range types.
+    (unstable, new_range, "CURRENT_RUSTC_VERSION", Some(123741)),
     /// Allows `#![no_core]`.
     (unstable, no_core, "1.3.0", Some(29639)),
     /// Allows the use of `no_sanitize` attribute.

diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
@@ -2313,6 +2313,18 @@ impl Expr<'_> {
                     [val2],
                     StructTailExpr::None,
                 ),
+            )
+            | (
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeFromCopy, _),
+                    [val1],
+                    StructTailExpr::None,
+                ),
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeFromCopy, _),
+                    [val2],
+                    StructTailExpr::None,
+                ),
             ) => val1.expr.equivalent_for_indexing(val2.expr),
             (
                 ExprKind::Struct(
@@ -2325,6 +2337,30 @@ impl Expr<'_> {
                     [val2, val4],
                     StructTailExpr::None,
                 ),
+            )
+            | (
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeCopy, _),
+                    [val1, val3],
+                    StructTailExpr::None,
+                ),
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeCopy, _),
+                    [val2, val4],
+                    StructTailExpr::None,
+                ),
+            )
+            | (
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeInclusiveCopy, _),
+                    [val1, val3],
+                    StructTailExpr::None,
+                ),
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeInclusiveCopy, _),
+                    [val2, val4],
+                    StructTailExpr::None,
+                ),
             ) => {
                 val1.expr.equivalent_for_indexing(val2.expr)
                     && val3.expr.equivalent_for_indexing(val4.expr)
@@ -2354,7 +2390,10 @@ pub fn is_range_literal(expr: &Expr<'_>) -> bool {
                     | LangItem::RangeTo
                     | LangItem::RangeFrom
                     | LangItem::RangeFull
-                    | LangItem::RangeToInclusive,
+                    | LangItem::RangeToInclusive
+                    | LangItem::RangeCopy
+                    | LangItem::RangeFromCopy
+                    | LangItem::RangeInclusiveCopy,
                 ..
             )
         ),

diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs
@@ -416,6 +416,11 @@ language_item_table! {
     RangeToInclusive,        sym::RangeToInclusive,    range_to_inclusive_struct,  Target::Struct,         GenericRequirement::None;
     RangeTo,                 sym::RangeTo,             range_to_struct,            Target::Struct,         GenericRequirement::None;
 
+    // `new_range` types that are `Copy + IntoIterator`
+    RangeFromCopy,           sym::RangeFromCopy,       range_from_copy_struct,     Target::Struct,         GenericRequirement::None;
+    RangeCopy,               sym::RangeCopy,           range_copy_struct,          Target::Struct,         GenericRequirement::None;
+    RangeInclusiveCopy,      sym::RangeInclusiveCopy,  range_inclusive_copy_struct, Target::Struct,         GenericRequirement::None;
+
     String,                  sym::String,              string,                     Target::Struct,         GenericRequirement::None;
     CStr,                    sym::CStr,                c_str,                      Target::Struct,         GenericRequirement::None;
 }

diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs
@@ -2395,6 +2395,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     let lang_item = match parent_expr.kind {
                         ExprKind::Struct(qpath, _, _) => match *qpath {
                             QPath::LangItem(LangItem::Range, ..) => Some(LangItem::Range),
+                            QPath::LangItem(LangItem::RangeCopy, ..) => Some(LangItem::RangeCopy),
+                            QPath::LangItem(LangItem::RangeInclusiveCopy, ..) => {
+                                Some(LangItem::RangeInclusiveCopy)
+                            }
                             QPath::LangItem(LangItem::RangeTo, ..) => Some(LangItem::RangeTo),
                             QPath::LangItem(LangItem::RangeToInclusive, ..) => {
                                 Some(LangItem::RangeToInclusive)

diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
@@ -294,9 +294,12 @@ symbols! {
         ProceduralMasqueradeDummyType,
         Range,
         RangeBounds,
+        RangeCopy,
         RangeFrom,
+        RangeFromCopy,
         RangeFull,
         RangeInclusive,
+        RangeInclusiveCopy,
         RangeTo,
         RangeToInclusive,
         Rc,
@@ -1364,6 +1367,7 @@ symbols! {
         new_lower_hex,
         new_octal,
         new_pointer,
+        new_range,
         new_unchecked,
         new_upper_exp,
         new_upper_hex,

diff --git a/library/core/src/range.rs b/library/core/src/range.rs
@@ -48,6 +48,7 @@ pub use crate::ops::{Bound, OneSidedRange, RangeBounds, RangeFull, RangeTo, Rang
 /// assert_eq!(Range::from(3..5), Range { start: 3, end: 5 });
 /// assert_eq!(3 + 4 + 5, Range::from(3..6).into_iter().sum());
 /// ```
+#[cfg_attr(not(bootstrap), lang = "RangeCopy")]
 #[derive(Clone, Copy, Default, PartialEq, Eq, Hash)]
 #[unstable(feature = "new_range_api", issue = "125687")]
 pub struct Range<Idx> {
@@ -205,6 +206,7 @@ impl<T> From<legacy::Range<T>> for Range<T> {
 /// assert_eq!(RangeInclusive::from(3..=5), RangeInclusive { start: 3, end: 5 });
 /// assert_eq!(3 + 4 + 5, RangeInclusive::from(3..=5).into_iter().sum());
 /// ```
+#[cfg_attr(not(bootstrap), lang = "RangeInclusiveCopy")]
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
 #[unstable(feature = "new_range_api", issue = "125687")]
 pub struct RangeInclusive<Idx> {
@@ -388,6 +390,7 @@ impl<T> From<legacy::RangeInclusive<T>> for RangeInclusive<T> {
 /// assert_eq!(RangeFrom::from(2..), core::range::RangeFrom { start: 2 });
 /// assert_eq!(2 + 3 + 4, RangeFrom::from(2..).into_iter().take(3).sum());
 /// ```
+#[cfg_attr(not(bootstrap), lang = "RangeFromCopy")]
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
 #[unstable(feature = "new_range_api", issue = "125687")]
 pub struct RangeFrom<Idx> {

diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
@@ -530,6 +530,8 @@ pub use core::option;
 pub use core::pin;
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::ptr;
+#[unstable(feature = "new_range_api", issue = "125687")]
+pub use core::range;
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::result;
 #[stable(feature = "rust1", since = "1.0.0")]

diff --git a/src/doc/unstable-book/src/language-features/new-range.md b/src/doc/unstable-book/src/language-features/new-range.md
@@ -0,0 +1,9 @@
+# `new_range`
+
+The tracking issue for this feature is: [#123741]
+
+[#123741]: https://github.com/rust-lang/rust/issues/123741
+
+---
+
+Switch the syntaxes `a..`, `a..b`, and `a..=b` to resolve the new range types.
diff --git a/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-abort.mir
@@ -19,16 +19,16 @@ fn inclusive_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {
         scope 2 {
             debug x => _9;
         }
-        scope 5 (inlined iter::range::<impl Iterator for RangeInclusive<u32>>::next) {
+        scope 5 (inlined iter::range::<impl Iterator for std::ops::RangeInclusive<u32>>::next) {
         }
     }
-    scope 3 (inlined RangeInclusive::<u32>::new) {
+    scope 3 (inlined std::ops::RangeInclusive::<u32>::new) {
     }
-    scope 4 (inlined <RangeInclusive<u32> as IntoIterator>::into_iter) {
+    scope 4 (inlined <std::ops::RangeInclusive<u32> as IntoIterator>::into_iter) {
     }
 
     bb0: {
-        _4 = RangeInclusive::<u32> { start: copy _1, end: copy _2, exhausted: const false };
+        _4 = std::ops::RangeInclusive::<u32> { start: copy _1, end: copy _2, exhausted: const false };
         StorageLive(_5);
         _5 = copy _4;
         goto -> bb1;
@@ -37,7 +37,7 @@ fn inclusive_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {
     bb1: {
         StorageLive(_7);
         _6 = &mut _5;
-        _7 = <RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _6) -> [return: bb2, unwind unreachable];
+        _7 = <std::ops::RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _6) -> [return: bb2, unwind unreachable];
     }
 
     bb2: {

diff --git a/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-unwind.mir
@@ -19,16 +19,16 @@ fn inclusive_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {
         scope 2 {
             debug x => _9;
         }
-        scope 5 (inlined iter::range::<impl Iterator for RangeInclusive<u32>>::next) {
+        scope 5 (inlined iter::range::<impl Iterator for std::ops::RangeInclusive<u32>>::next) {
         }
     }
-    scope 3 (inlined RangeInclusive::<u32>::new) {
+    scope 3 (inlined std::ops::RangeInclusive::<u32>::new) {
     }
-    scope 4 (inlined <RangeInclusive<u32> as IntoIterator>::into_iter) {
+    scope 4 (inlined <std::ops::RangeInclusive<u32> as IntoIterator>::into_iter) {
     }
 
     bb0: {
-        _4 = RangeInclusive::<u32> { start: copy _1, end: copy _2, exhausted: const false };
+        _4 = std::ops::RangeInclusive::<u32> { start: copy _1, end: copy _2, exhausted: const false };
         StorageLive(_5);
         _5 = copy _4;
         goto -> bb1;
@@ -37,7 +37,7 @@ fn inclusive_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {
     bb1: {
         StorageLive(_7);
         _6 = &mut _5;
-        _7 = <RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _6) -> [return: bb2, unwind: bb8];
+        _7 = <std::ops::RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _6) -> [return: bb2, unwind: bb8];
     }
 
     bb2: {

diff --git a/...mir-opt/pre-codegen/range_iter.range_inclusive_iter_next.PreCodegen.after.panic-abort.mir b/...mir-opt/pre-codegen/range_iter.range_inclusive_iter_next.PreCodegen.after.panic-abort.mir
@@ -1,13 +1,13 @@
 // MIR for `range_inclusive_iter_next` after PreCodegen
 
-fn range_inclusive_iter_next(_1: &mut RangeInclusive<u32>) -> Option<u32> {
+fn range_inclusive_iter_next(_1: &mut std::ops::RangeInclusive<u32>) -> Option<u32> {
     debug it => _1;
     let mut _0: std::option::Option<u32>;
-    scope 1 (inlined iter::range::<impl Iterator for RangeInclusive<u32>>::next) {
+    scope 1 (inlined iter::range::<impl Iterator for std::ops::RangeInclusive<u32>>::next) {
     }
 
     bb0: {
-        _0 = <RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _1) -> [return: bb1, unwind unreachable];
+        _0 = <std::ops::RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _1) -> [return: bb1, unwind unreachable];
     }
 
     bb1: {

diff --git a/...ir-opt/pre-codegen/range_iter.range_inclusive_iter_next.PreCodegen.after.panic-unwind.mir b/...ir-opt/pre-codegen/range_iter.range_inclusive_iter_next.PreCodegen.after.panic-unwind.mir
@@ -1,13 +1,13 @@
 // MIR for `range_inclusive_iter_next` after PreCodegen
 
-fn range_inclusive_iter_next(_1: &mut RangeInclusive<u32>) -> Option<u32> {
+fn range_inclusive_iter_next(_1: &mut std::ops::RangeInclusive<u32>) -> Option<u32> {
     debug it => _1;
     let mut _0: std::option::Option<u32>;
-    scope 1 (inlined iter::range::<impl Iterator for RangeInclusive<u32>>::next) {
+    scope 1 (inlined iter::range::<impl Iterator for std::ops::RangeInclusive<u32>>::next) {
     }
 
     bb0: {
-        _0 = <RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _1) -> [return: bb1, unwind continue];
+        _0 = <std::ops::RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _1) -> [return: bb1, unwind continue];
     }
 
     bb1: {

diff --git a/tests/ui/const-generics/std/const-generics-range.full.stderr b/tests/ui/const-generics/std/const-generics-range.full.stderr
@@ -4,7 +4,7 @@ error[E0741]: `std::ops::Range<usize>` must implement `ConstParamTy` to be used
 LL | struct _Range<const R: std::ops::Range<usize>>;
    |                        ^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0741]: `RangeFrom<usize>` must implement `ConstParamTy` to be used as the type of a const generic parameter
+error[E0741]: `std::ops::RangeFrom<usize>` must implement `ConstParamTy` to be used as the type of a const generic parameter
   --> $DIR/const-generics-range.rs:13:28
    |
 LL | struct _RangeFrom<const R: std::ops::RangeFrom<usize>>;
@@ -16,7 +16,7 @@ error[E0741]: `RangeFull` must implement `ConstParamTy` to be used as the type o
 LL | struct _RangeFull<const R: std::ops::RangeFull>;
    |                            ^^^^^^^^^^^^^^^^^^^
 
-error[E0741]: `RangeInclusive<usize>` must implement `ConstParamTy` to be used as the type of a const generic parameter
+error[E0741]: `std::ops::RangeInclusive<usize>` must implement `ConstParamTy` to be used as the type of a const generic parameter
   --> $DIR/const-generics-range.rs:24:33
    |
 LL | struct _RangeInclusive<const R: std::ops::RangeInclusive<usize>>;

diff --git a/tests/ui/const-generics/std/const-generics-range.min.stderr b/tests/ui/const-generics/std/const-generics-range.min.stderr
@@ -10,7 +10,7 @@ help: add `#![feature(adt_const_params)]` to the crate attributes to enable more
 LL + #![feature(adt_const_params)]
    |
 
-error: `RangeFrom<usize>` is forbidden as the type of a const generic parameter
+error: `std::ops::RangeFrom<usize>` is forbidden as the type of a const generic parameter
   --> $DIR/const-generics-range.rs:13:28
    |
 LL | struct _RangeFrom<const R: std::ops::RangeFrom<usize>>;
@@ -34,7 +34,7 @@ help: add `#![feature(adt_const_params)]` to the crate attributes to enable more
 LL + #![feature(adt_const_params)]
    |
 
-error: `RangeInclusive<usize>` is forbidden as the type of a const generic parameter
+error: `std::ops::RangeInclusive<usize>` is forbidden as the type of a const generic parameter
   --> $DIR/const-generics-range.rs:24:33
    |
 LL | struct _RangeInclusive<const R: std::ops::RangeInclusive<usize>>;

diff --git a/tests/ui/const-generics/std/const-generics-range.rs b/tests/ui/const-generics/std/const-generics-range.rs
@@ -11,7 +11,7 @@ const RANGE : _Range<{ 0 .. 1000 }> = _Range;
 
 // `RangeFrom` should be usable within const generics:
 struct _RangeFrom<const R: std::ops::RangeFrom<usize>>;
-//[min]~^ ERROR `RangeFrom<usize>` is forbidden
+//[min]~^ ERROR `std::ops::RangeFrom<usize>` is forbidden
 const RANGE_FROM : _RangeFrom<{ 0 .. }> = _RangeFrom;
 
 // `RangeFull` should be usable within const generics:
@@ -22,7 +22,7 @@ const RANGE_FULL : _RangeFull<{ .. }> = _RangeFull;
 // Regression test for #70155
 // `RangeInclusive` should be usable within const generics:
 struct _RangeInclusive<const R: std::ops::RangeInclusive<usize>>;
-//[min]~^ ERROR `RangeInclusive<usize>` is forbidden
+//[min]~^ ERROR `std::ops::RangeInclusive<usize>` is forbidden
 const RANGE_INCLUSIVE : _RangeInclusive<{ 0 ..= 999 }> = _RangeInclusive;
 
 // `RangeTo` should be usable within const generics:

diff --git a/tests/ui/feature-gates/feature-gate-new_range.rs b/tests/ui/feature-gates/feature-gate-new_range.rs
@@ -0,0 +1,10 @@
+#![feature(new_range_api)]
+
+fn main() {
+    let a: core::range::RangeFrom<u8> = 1..;
+    //~^ mismatched types
+    let b: core::range::Range<u8> = 2..3;
+    //~^ mismatched types
+    let c: core::range::RangeInclusive<u8> = 4..=5;
+    //~^ mismatched types
+}