Rollup merge of #59266 - estebank:struct-parse-recovery, r=petrochenkov

Do not complain about non-existing fields after parse recovery

When failing to parse struct-like enum variants, the ADT gets recorded
as having no fields. Record that we have actually recovered during
parsing of this variant to avoid complaing about non-existing fields
when actually using it.

Fix #57361.

1 files changed, 20 insertions, 10 deletions

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 7a4a687f90e..648ee771ddb 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -6837,14 +6837,16 @@ impl<'a> Parser<'a> {
                 VariantData::Unit(ast::DUMMY_NODE_ID)
             } else {
                 // If we see: `struct Foo<T> where T: Copy { ... }`
-                VariantData::Struct(self.parse_record_struct_body()?, ast::DUMMY_NODE_ID)
+                let (fields, recovered) = self.parse_record_struct_body()?;
+                VariantData::Struct(fields, ast::DUMMY_NODE_ID, recovered)
             }
         // No `where` so: `struct Foo<T>;`
         } else if self.eat(&token::Semi) {
             VariantData::Unit(ast::DUMMY_NODE_ID)
         // Record-style struct definition
         } else if self.token == token::OpenDelim(token::Brace) {
-            VariantData::Struct(self.parse_record_struct_body()?, ast::DUMMY_NODE_ID)
+            let (fields, recovered) = self.parse_record_struct_body()?;
+            VariantData::Struct(fields, ast::DUMMY_NODE_ID, recovered)
         // Tuple-style struct definition with optional where-clause.
         } else if self.token == token::OpenDelim(token::Paren) {
             let body = VariantData::Tuple(self.parse_tuple_struct_body()?, ast::DUMMY_NODE_ID);
@@ -6872,9 +6874,11 @@ impl<'a> Parser<'a> {
 
         let vdata = if self.token.is_keyword(keywords::Where) {
             generics.where_clause = self.parse_where_clause()?;
-            VariantData::Struct(self.parse_record_struct_body()?, ast::DUMMY_NODE_ID)
+            let (fields, recovered) = self.parse_record_struct_body()?;
+            VariantData::Struct(fields, ast::DUMMY_NODE_ID, recovered)
         } else if self.token == token::OpenDelim(token::Brace) {
-            VariantData::Struct(self.parse_record_struct_body()?, ast::DUMMY_NODE_ID)
+            let (fields, recovered) = self.parse_record_struct_body()?;
+            VariantData::Struct(fields, ast::DUMMY_NODE_ID, recovered)
         } else {
             let token_str = self.this_token_descr();
             let mut err = self.fatal(&format!(
@@ -6906,12 +6910,16 @@ impl<'a> Parser<'a> {
         }
     }
 
-    fn parse_record_struct_body(&mut self) -> PResult<'a, Vec<StructField>> {
+    fn parse_record_struct_body(
+        &mut self,
+    ) -> PResult<'a, (Vec<StructField>, /* recovered */ bool)> {
         let mut fields = Vec::new();
+        let mut recovered = false;
         if self.eat(&token::OpenDelim(token::Brace)) {
             while self.token != token::CloseDelim(token::Brace) {
                 let field = self.parse_struct_decl_field().map_err(|e| {
                     self.recover_stmt();
+                    recovered = true;
                     e
                 });
                 match field {
@@ -6930,7 +6938,7 @@ impl<'a> Parser<'a> {
             return Err(err);
         }
 
-        Ok(fields)
+        Ok((fields, recovered))
     }
 
     fn parse_tuple_struct_body(&mut self) -> PResult<'a, Vec<StructField>> {
@@ -7693,12 +7701,14 @@ impl<'a> Parser<'a> {
             if self.check(&token::OpenDelim(token::Brace)) {
                 // Parse a struct variant.
                 all_nullary = false;
-                struct_def = VariantData::Struct(self.parse_record_struct_body()?,
-                                                 ast::DUMMY_NODE_ID);
+                let (fields, recovered) = self.parse_record_struct_body()?;
+                struct_def = VariantData::Struct(fields, ast::DUMMY_NODE_ID, recovered);
             } else if self.check(&token::OpenDelim(token::Paren)) {
                 all_nullary = false;
-                struct_def = VariantData::Tuple(self.parse_tuple_struct_body()?,
-                                                ast::DUMMY_NODE_ID);
+                struct_def = VariantData::Tuple(
+                    self.parse_tuple_struct_body()?,
+                    ast::DUMMY_NODE_ID,
+                );
             } else if self.eat(&token::Eq) {
                 disr_expr = Some(AnonConst {
                     id: ast::DUMMY_NODE_ID,