Auto merge of rust-lang#16553 - Veykril:field-lit-recovery, r=Veykril

fix: Imrpove recover on `=` for record field initializer and pattern

Author: bors

crates/parser/src/grammar/expressions.rs

@@ -678,27 +678,38 @@ pub(crate) fn record_expr_field_list(p: &mut Parser<'_>) {
         attributes::outer_attrs(p);
 
         match p.current() {
-            IDENT | INT_NUMBER => {
+            IDENT | INT_NUMBER if p.nth_at(1, T![::]) => {
                 // test_err record_literal_missing_ellipsis_recovery
                 // fn main() {
                 //     S { S::default() }
                 // }
-                if p.nth_at(1, T![::]) {
-                    m.abandon(p);
-                    p.expect(T![..]);
-                    expr(p);
-                } else {
+                m.abandon(p);
+                p.expect(T![..]);
+                expr(p);
+            }
+            IDENT | INT_NUMBER => {
+                if p.nth_at(1, T![..]) {
                     // test_err record_literal_before_ellipsis_recovery
                     // fn main() {
                     //     S { field ..S::default() }
                     // }
-                    if p.nth_at(1, T![:]) || p.nth_at(1, T![..]) {
+                    name_ref_or_index(p);
+                    p.error("expected `:`");
+                } else {
+                    // test_err record_literal_field_eq_recovery
+                    // fn main() {
+                    //     S { field = foo }
+                    // }
+                    if p.nth_at(1, T![:]) {
+                        name_ref_or_index(p);
+                        p.bump(T![:]);
+                    } else if p.nth_at(1, T![=]) {
                         name_ref_or_index(p);
-                        p.expect(T![:]);
+                        p.err_and_bump("expected `:`");
                     }
                     expr(p);
-                    m.complete(p, RECORD_EXPR_FIELD);
                 }
+                m.complete(p, RECORD_EXPR_FIELD);
             }
             T![.] if p.at(T![..]) => {
                 m.abandon(p);

crates/parser/src/grammar/patterns.rs

@@ -323,6 +323,15 @@ fn record_pat_field(p: &mut Parser<'_>) {
             p.bump(T![:]);
             pattern(p);
         }
+        // test_err record_pat_field_eq_recovery
+        // fn main() {
+        //     let S { field = foo };
+        // }
+        IDENT | INT_NUMBER if p.nth(1) == T![=] => {
+            name_ref_or_index(p);
+            p.err_and_bump("expected `:`");
+            pattern(p);
+        }
         T![box] => {
             // FIXME: not all box patterns should be allowed
             box_pat(p);

crates/parser/test_data/parser/inline/err/0014_record_literal_before_ellipsis_recovery.rast

@@ -24,26 +24,26 @@ SOURCE_FILE
             RECORD_EXPR_FIELD
               NAME_REF
                 IDENT "field"
-              WHITESPACE " "
-              RANGE_EXPR
-                DOT2 ".."
-                CALL_EXPR
-                  PATH_EXPR
-                    PATH
-                      PATH
-                        PATH_SEGMENT
-                          NAME_REF
-                            IDENT "S"
-                      COLON2 "::"
-                      PATH_SEGMENT
-                        NAME_REF
-                          IDENT "default"
-                  ARG_LIST
-                    L_PAREN "("
-                    R_PAREN ")"
+            WHITESPACE " "
+            DOT2 ".."
+            CALL_EXPR
+              PATH_EXPR
+                PATH
+                  PATH
+                    PATH_SEGMENT
+                      NAME_REF
+                        IDENT "S"
+                  COLON2 "::"
+                  PATH_SEGMENT
+                    NAME_REF
+                      IDENT "default"
+              ARG_LIST
+                L_PAREN "("
+                R_PAREN ")"
             WHITESPACE " "
             R_CURLY "}"
         WHITESPACE "\n"
         R_CURLY "}"
   WHITESPACE "\n"
-error 25: expected COLON
+error 25: expected `:`
+error 25: expected COMMA

crates/parser/test_data/parser/inline/err/0032_record_literal_field_eq_recovery.rast

@@ -0,0 +1,41 @@
+SOURCE_FILE
+  FN
+    FN_KW "fn"
+    WHITESPACE " "
+    NAME
+      IDENT "main"
+    PARAM_LIST
+      L_PAREN "("
+      R_PAREN ")"
+    WHITESPACE " "
+    BLOCK_EXPR
+      STMT_LIST
+        L_CURLY "{"
+        WHITESPACE "\n    "
+        RECORD_EXPR
+          PATH
+            PATH_SEGMENT
+              NAME_REF
+                IDENT "S"
+          WHITESPACE " "
+          RECORD_EXPR_FIELD_LIST
+            L_CURLY "{"
+            WHITESPACE " "
+            RECORD_EXPR_FIELD
+              NAME_REF
+                IDENT "field"
+              WHITESPACE " "
+              ERROR
+                EQ "="
+              WHITESPACE " "
+              PATH_EXPR
+                PATH
+                  PATH_SEGMENT
+                    NAME_REF
+                      IDENT "foo"
+            WHITESPACE " "
+            R_CURLY "}"
+        WHITESPACE "\n"
+        R_CURLY "}"
+  WHITESPACE "\n"
+error 26: expected `:`

crates/parser/test_data/parser/inline/err/0032_record_literal_field_eq_recovery.rs

@@ -0,0 +1,3 @@
+fn main() {
+    S { field = foo }
+}

crates/parser/test_data/parser/inline/err/0033_record_pat_field_eq_recovery.rast

@@ -0,0 +1,43 @@
+SOURCE_FILE
+  FN
+    FN_KW "fn"
+    WHITESPACE " "
+    NAME
+      IDENT "main"
+    PARAM_LIST
+      L_PAREN "("
+      R_PAREN ")"
+    WHITESPACE " "
+    BLOCK_EXPR
+      STMT_LIST
+        L_CURLY "{"
+        WHITESPACE "\n    "
+        LET_STMT
+          LET_KW "let"
+          WHITESPACE " "
+          RECORD_PAT
+            PATH
+              PATH_SEGMENT
+                NAME_REF
+                  IDENT "S"
+            WHITESPACE " "
+            RECORD_PAT_FIELD_LIST
+              L_CURLY "{"
+              WHITESPACE " "
+              RECORD_PAT_FIELD
+                NAME_REF
+                  IDENT "field"
+                WHITESPACE " "
+                ERROR
+                  EQ "="
+                WHITESPACE " "
+                IDENT_PAT
+                  NAME
+                    IDENT "foo"
+              WHITESPACE " "
+              R_CURLY "}"
+          SEMICOLON ";"
+        WHITESPACE "\n"
+        R_CURLY "}"
+  WHITESPACE "\n"
+error 30: expected `:`

crates/parser/test_data/parser/inline/err/0033_record_pat_field_eq_recovery.rs

@@ -0,0 +1,3 @@
+fn main() {
+    let S { field = foo };
+}