Rollup merge of #106919 - compiler-errors:underscore-typo-in-field-pat, r=jackh726

Recover `_` as `..` in field pattern

2 files changed, 15 insertions, 8 deletions

diff --git a/compiler/rustc_parse/src/errors.rs b/compiler/rustc_parse/src/errors.rs
index 145611923ff..20da8ce5b6e 100644
--- a/compiler/rustc_parse/src/errors.rs
+++ b/compiler/rustc_parse/src/errors.rs
@@ -1,3 +1,5 @@
+use std::borrow::Cow;
+
 use rustc_ast::token::Token;
 use rustc_ast::{Path, Visibility};
 use rustc_errors::{fluent, AddToDiagnostic, Applicability, EmissionGuarantee, IntoDiagnostic};
@@ -1802,8 +1804,9 @@ pub(crate) struct EnumPatternInsteadOfIdentifier {
 #[diag(parse_dot_dot_dot_for_remaining_fields)]
 pub(crate) struct DotDotDotForRemainingFields {
     #[primary_span]
-    #[suggestion(code = "..", applicability = "machine-applicable")]
+    #[suggestion(code = "..", style = "verbose", applicability = "machine-applicable")]
     pub span: Span,
+    pub token_str: Cow<'static, str>,
 }
 
 #[derive(Diagnostic)]
diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs
index e75554ba124..0e8b549b438 100644
--- a/compiler/rustc_parse/src/parser/pat.rs
+++ b/compiler/rustc_parse/src/parser/pat.rs
@@ -962,12 +962,15 @@ impl<'a> Parser<'a> {
             }
             ate_comma = false;
 
-            if self.check(&token::DotDot) || self.token == token::DotDotDot {
+            if self.check(&token::DotDot)
+                || self.check_noexpect(&token::DotDotDot)
+                || self.check_keyword(kw::Underscore)
+            {
                 etc = true;
                 let mut etc_sp = self.token.span;
 
-                self.recover_one_fewer_dotdot();
-                self.bump(); // `..` || `...`
+                self.recover_bad_dot_dot();
+                self.bump(); // `..` || `...` || `_`
 
                 if self.token == token::CloseDelim(Delimiter::Brace) {
                     etc_span = Some(etc_sp);
@@ -1060,14 +1063,15 @@ impl<'a> Parser<'a> {
         Ok((fields, etc))
     }
 
-    /// Recover on `...` as if it were `..` to avoid further errors.
+    /// Recover on `...` or `_` as if it were `..` to avoid further errors.
     /// See issue #46718.
-    fn recover_one_fewer_dotdot(&self) {
-        if self.token != token::DotDotDot {
+    fn recover_bad_dot_dot(&self) {
+        if self.token == token::DotDot {
             return;
         }
 
-        self.sess.emit_err(DotDotDotForRemainingFields { span: self.token.span });
+        let token_str = pprust::token_to_string(&self.token);
+        self.sess.emit_err(DotDotDotForRemainingFields { span: self.token.span, token_str });
     }
 
     fn parse_pat_field(&mut self, lo: Span, attrs: AttrVec) -> PResult<'a, PatField> {