Rollup merge of #112642 - compiler-errors:interp-lit-err, r=nnethercote

Handle interpolated literal errors

Not sure why it was doing a whole dance to re-match on the token kind when it seems like `Lit::from_token` does the right thing for both macro-arg and regular literals. Nothing seems to have regressed diagnostics-wise from the change, though.

Fixes #112622

r? ``@nnethercote``

1 files changed, 3 insertions, 6 deletions

diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs
index cea2a71c988..f00bc54589a 100644
--- a/compiler/rustc_parse/src/parser/expr.rs
+++ b/compiler/rustc_parse/src/parser/expr.rs
@@ -2023,17 +2023,14 @@ impl<'a> Parser<'a> {
         let recovered = self.recover_after_dot();
         let token = recovered.as_ref().unwrap_or(&self.token);
         match token::Lit::from_token(token) {
-            Some(token_lit) => {
-                match MetaItemLit::from_token_lit(token_lit, token.span) {
+            Some(lit) => {
+                match MetaItemLit::from_token_lit(lit, token.span) {
                     Ok(lit) => {
                         self.bump();
                         Some(lit)
                     }
                     Err(err) => {
-                        let span = token.span;
-                        let token::Literal(lit) = token.kind else {
-                            unreachable!();
-                        };
+                        let span = token.uninterpolated_span();
                         self.bump();
                         report_lit_error(&self.sess, err, lit, span);
                         // Pack possible quotes and prefixes from the original literal into