Fix span bug

Author: camelid

compiler/rustc_parse/src/parser/expr.rs

@@ -1075,7 +1075,7 @@ impl<'a> Parser<'a> {
         } else if self.eat_keyword(kw::Unsafe) {
             self.parse_block_expr(None, lo, BlockCheckMode::Unsafe(ast::UserProvided), attrs)
         } else if self.eat_keyword(kw::Const) {
-            self.parse_const_block(lo.to(self.token.span))
+            self.parse_const_block(lo.to(self.prev_token.span))
         } else if self.is_do_catch_block() {
             self.recover_do_catch(attrs)
         } else if self.is_try_block() {

compiler/rustc_parse/src/parser/pat.rs

@@ -339,7 +339,7 @@ impl<'a> Parser<'a> {
             PatKind::Box(pat)
         } else if self.eat_keyword(kw::Const) {
             // Parse `const { pat }`
-            let const_expr = self.parse_const_block(lo.to(self.token.span))?;
+            let const_expr = self.parse_const_block(lo.to(self.prev_token.span))?;
 
             if let Some(re) = self.parse_range_end() {
                 self.parse_pat_range_begin_with(const_expr, re)?
@@ -755,7 +755,7 @@ impl<'a> Parser<'a> {
     fn parse_pat_range_end(&mut self) -> PResult<'a, P<Expr>> {
         if self.check_inline_const(0) {
             self.eat_keyword(kw::Const);
-            self.parse_const_block(self.token.span)
+            self.parse_const_block(self.prev_token.span)
         } else if self.check_path() {
             let lo = self.token.span;
             let (qself, path) = if self.eat_lt() {

src/test/ui/feature-gate-inline_const.stderr

@@ -2,7 +2,7 @@ error[E0658]: inline-const is experimental
   --> $DIR/feature-gate-inline_const.rs:2:13
    |
 LL |     let _ = const {
-   |             ^^^^^^^
+   |             ^^^^^
    |
    = note: see issue #76001 <https://github.com/rust-lang/rust/issues/76001> for more information
    = help: add `#![feature(inline_const)]` to the crate attributes to enable

src/test/ui/parser/keyword-const-as-identifier.stderr

@@ -8,7 +8,7 @@ error[E0658]: inline-const is experimental
   --> $DIR/keyword-const-as-identifier.rs:2:9
    |
 LL |     let const = "foo";
-   |         ^^^^^^^
+   |         ^^^^^
    |
    = note: see issue #76001 <https://github.com/rust-lang/rust/issues/76001> for more information
    = help: add `#![feature(inline_const)]` to the crate attributes to enable