fix: allow reserved keywords as business event message/attribute names (issue #476)

businessEventMessageDef and businessEventAttrDef both used IDENTIFIER, which
rejects any token that is also a reserved keyword (Date, Amount, Timestamp, etc.)
— common attribute names in real domain models.

Changed both rules to identifierOrKeyword and updated the visitor to read the
name via identifierOrKeywordText(). Regenerated ANTLR parser.

Added regression test TestBusinessEvent_KeywordAttributeNames to prevent recurrence.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: ako

mdl/executor/bugfix_regression_test.go

@@ -870,3 +870,22 @@ func TestValidateMicroflowReferencesReportsIncludedMissingMicroflow(t *testing.T
 		t.Fatalf("unexpected validation error: %v", err)
 	}
 }
+
+// =============================================================================
+// Issue #476: Business event MESSAGE attribute names reject reserved keywords
+// =============================================================================
+
+// TestBusinessEvent_KeywordAttributeNames verifies that reserved keywords (Date,
+// Amount, etc.) are accepted as MESSAGE attribute names and message names.
+func TestBusinessEvent_KeywordAttributeNames(t *testing.T) {
+	input := `CREATE BUSINESS EVENT SERVICE MyModule.Events
+(ServiceName: 'Svc', EventNamePrefix: 'com.test')
+{
+  MESSAGE OrderCreated (Date: DateTime, Amount: Decimal) PUBLISH ENTITY MyModule.Order;
+};`
+
+	_, errs := visitor.Build(input)
+	if len(errs) > 0 {
+		t.Fatalf("issue #476: keyword attribute names rejected: %v", errs[0])
+	}
+}

mdl/grammar/MDLParser.g4

@@ -2874,7 +2874,7 @@ createBusinessEventServiceStatement
     ;
 
 businessEventMessageDef
-    : MESSAGE IDENTIFIER
+    : MESSAGE identifierOrKeyword
       LPAREN businessEventAttrDef (COMMA businessEventAttrDef)* RPAREN
       (PUBLISH | SUBSCRIBE)
       (ENTITY qualifiedName)?
@@ -2883,7 +2883,7 @@ businessEventMessageDef
     ;
 
 businessEventAttrDef
-    : IDENTIFIER COLON dataType
+    : identifierOrKeyword COLON dataType
     ;
 
 // =============================================================================

mdl/grammar/parser/MDLParser.interp

@@ -39,8 +39,8 @@ func (b *Builder) ExitCreateBusinessEventServiceStatement(ctx *parser.CreateBusi
 		}
 
 		msg := &ast.BusinessEventMessageDef{}
-		if id := msgDef.IDENTIFIER(); id != nil {
-			msg.MessageName = id.GetText()
+		if iok := msgDef.IdentifierOrKeyword(); iok != nil {
+			msg.MessageName = identifierOrKeywordText(iok)
 		}
 
 		// Parse operation (PUBLISH or SUBSCRIBE)
@@ -71,8 +71,8 @@ func (b *Builder) ExitCreateBusinessEventServiceStatement(ctx *parser.CreateBusi
 			attr := &ast.BusinessEventAttributeDef{
 				TypeName: dataTypeSimpleName(attrDef.DataType()),
 			}
-			if id := attrDef.IDENTIFIER(); id != nil {
-				attr.Name = id.GetText()
+			if iok := attrDef.IdentifierOrKeyword(); iok != nil {
+				attr.Name = identifierOrKeywordText(iok)
 			}
 			msg.Attributes = append(msg.Attributes, attr)
 		}