[vala/staging] parser: Minor semantic checks to improve error messages

[Rico Tzschichholz <ricotz src gnome org>]

commit cbc11c2674209c3c51eb5c9851863dacea13366b
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Thu Apr 15 16:49:14 2021 +0200

    parser: Minor semantic checks to improve error messages

 vala/valaparser.vala | 15 +++++++++++++++
 1 file changed, 15 insertions(+)
---
diff --git a/vala/valaparser.vala b/vala/valaparser.vala
index bad086982..cba7c51b2 100644
--- a/vala/valaparser.vala
+++ b/vala/valaparser.vala
@@ -2497,12 +2497,18 @@ public class Vala.Parser : CodeVisitor {
                case TokenType.CONSTRUCT:
                        if (context.profile == Profile.GOBJECT) {
                                rollback (begin);
+                               if (!(parent is TypeSymbol)) {
+                                       throw new ParseError.SYNTAX ("unexpected `construct' declaration");
+                               }
                                parse_constructor_declaration (parent, attrs);
                                return;
                        }
                        break;
                case TokenType.TILDE:
                        rollback (begin);
+                       if (!(parent is TypeSymbol)) {
+                               throw new ParseError.SYNTAX ("unexpected `destructor' declaration");
+                       }
                        parse_destructor_declaration (parent, attrs);
                        return;
                case TokenType.OPEN_BRACE:
@@ -2581,6 +2587,9 @@ public class Vala.Parser : CodeVisitor {
                                break;
                        case TokenType.OPEN_PARENS:
                                rollback (begin);
+                               if (!(parent is TypeSymbol)) {
+                                       throw new ParseError.SYNTAX ("unexpected `constructor' declaration");
+                               }
                                parse_creation_method_declaration (parent, attrs);
                                return;
                        default:
@@ -2593,6 +2602,9 @@ public class Vala.Parser : CodeVisitor {
                                                parse_delegate_declaration (parent, attrs);
                                                return;
                                        case TokenType.SIGNAL:
+                                               if (!(parent is ObjectTypeSymbol)) {
+                                                       throw new ParseError.SYNTAX ("unexpected `signal' 
declaration");
+                                               }
                                                parse_signal_declaration (parent, attrs);
                                                return;
                                        default:
@@ -2613,6 +2625,9 @@ public class Vala.Parser : CodeVisitor {
                                case TokenType.OPEN_BRACE:
                                case TokenType.THROWS:
                                        rollback (begin);
+                                       if (!(parent is TypeSymbol)) {
+                                               throw new ParseError.SYNTAX ("unexpected `property' 
declaration");
+                                       }
                                        parse_property_declaration (parent, attrs);
                                        return;
                                default: