Rollup merge of #144765 - Qelxiros:range-inclusive-last, r=jhpratt

inclusive `Range`s: change `end` to `last`

Tracking issue: rust-lang/rust#125687
ACP: rust-lang/libs-team#511

5 files changed, 56 insertions, 6 deletions

diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs
index 3674814b796..bb6b25baf01 100644
--- a/compiler/rustc_ast_lowering/src/expr.rs
+++ b/compiler/rustc_ast_lowering/src/expr.rs
@@ -1536,7 +1536,13 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     hir::LangItem::Range
                 }
             }
-            (None, Some(..), Closed) => hir::LangItem::RangeToInclusive,
+            (None, Some(..), Closed) => {
+                if self.tcx.features().new_range() {
+                    hir::LangItem::RangeToInclusiveCopy
+                } else {
+                    hir::LangItem::RangeToInclusive
+                }
+            }
             (Some(e1), Some(e2), Closed) => {
                 if self.tcx.features().new_range() {
                     hir::LangItem::RangeInclusiveCopy
@@ -1560,13 +1566,26 @@ impl<'hir> LoweringContext<'_, 'hir> {
         };
 
         let fields = self.arena.alloc_from_iter(
-            e1.iter().map(|e| (sym::start, e)).chain(e2.iter().map(|e| (sym::end, e))).map(
-                |(s, e)| {
+            e1.iter()
+                .map(|e| (sym::start, e))
+                .chain(e2.iter().map(|e| {
+                    (
+                        if matches!(
+                            lang_item,
+                            hir::LangItem::RangeInclusiveCopy | hir::LangItem::RangeToInclusiveCopy
+                        ) {
+                            sym::last
+                        } else {
+                            sym::end
+                        },
+                        e,
+                    )
+                }))
+                .map(|(s, e)| {
                     let expr = self.lower_expr(e);
                     let ident = Ident::new(s, self.lower_span(e.span));
                     self.expr_field(ident, expr, e.span)
-                },
-            ),
+                }),
         );
 
         hir::ExprKind::Struct(
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index ae03121e5f7..75551fe4c19 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -2616,6 +2616,18 @@ impl Expr<'_> {
             )
             | (
                 ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeToInclusiveCopy, _),
+                    [val1],
+                    StructTailExpr::None,
+                ),
+                ExprKind::Struct(
+                    QPath::LangItem(LangItem::RangeToInclusiveCopy, _),
+                    [val2],
+                    StructTailExpr::None,
+                ),
+            )
+            | (
+                ExprKind::Struct(
                     QPath::LangItem(LangItem::RangeFrom, _),
                     [val1],
                     StructTailExpr::None,
@@ -2705,7 +2717,8 @@ pub fn is_range_literal(expr: &Expr<'_>) -> bool {
                     | LangItem::RangeToInclusive
                     | LangItem::RangeCopy
                     | LangItem::RangeFromCopy
-                    | LangItem::RangeInclusiveCopy,
+                    | LangItem::RangeInclusiveCopy
+                    | LangItem::RangeToInclusiveCopy,
                 ..
             )
         ),
diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs
index 0464665b41f..67d2f15d414 100644
--- a/compiler/rustc_hir/src/lang_items.rs
+++ b/compiler/rustc_hir/src/lang_items.rs
@@ -422,6 +422,7 @@ language_item_table! {
     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;
+    RangeToInclusiveCopy,    sym::RangeToInclusiveCopy,     range_to_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_index/src/idx.rs b/compiler/rustc_index/src/idx.rs
index 33f406e2113..9cd7134659c 100644
--- a/compiler/rustc_index/src/idx.rs
+++ b/compiler/rustc_index/src/idx.rs
@@ -130,7 +130,22 @@ impl<I: Idx, T> IntoSliceIdx<I, [T]> for core::range::RangeFrom<I> {
 impl<I: Idx, T> IntoSliceIdx<I, [T]> for core::range::RangeInclusive<I> {
     type Output = core::range::RangeInclusive<usize>;
     #[inline]
+    #[cfg(bootstrap)]
     fn into_slice_idx(self) -> Self::Output {
         core::range::RangeInclusive { start: self.start.index(), end: self.end.index() }
     }
+    #[inline]
+    #[cfg(not(bootstrap))]
+    fn into_slice_idx(self) -> Self::Output {
+        core::range::RangeInclusive { start: self.start.index(), last: self.last.index() }
+    }
+}
+
+#[cfg(all(feature = "nightly", not(bootstrap)))]
+impl<I: Idx, T> IntoSliceIdx<I, [T]> for core::range::RangeToInclusive<I> {
+    type Output = core::range::RangeToInclusive<usize>;
+    #[inline]
+    fn into_slice_idx(self) -> Self::Output {
+        core::range::RangeToInclusive { last: self.last.index() }
+    }
 }
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index e5108d8b7e9..ffdc640c285 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -326,6 +326,7 @@ symbols! {
         RangeSub,
         RangeTo,
         RangeToInclusive,
+        RangeToInclusiveCopy,
         Rc,
         RcWeak,
         Ready,
@@ -1280,6 +1281,7 @@ symbols! {
         lang,
         lang_items,
         large_assignments,
+        last,
         lateout,
         lazy_normalization_consts,
         lazy_type_alias,