HHH-14148 Fix ANTLR grammar non-determinism

hibernate-core/src/main/antlr/sql-gen.g

@@ -146,7 +146,7 @@ selectStatement
 		from
 		( #(WHERE { out(" where "); } whereExpr ) )?
 		( #(GROUP { out(" group by "); } groupExprs ( #(HAVING { out(" having "); } booleanExpr[false]) )? ) )?
-		( #(ORDER { out(" order by "); } orderBySqlFragmentOrExprs ) )?
+		( #(ORDER { out(" order by "); } orderExprs ) )?
 	)
 	;
 
@@ -191,18 +191,15 @@ whereClauseExpr
 	| booleanExpr[ false ]
 	;
 
-orderBySqlFragmentOrExprs
-	: sqlToken // for the purpose of mapping-defined orderBy SQL fragment
-	| orderExprs
-	;
-
 orderExprs { String ordExp = null; String ordDir = null; String ordNul = null; }
 	// TODO: remove goofy space before the comma when we don't have to regression test anymore.
 	// Dialect is provided a hook to render each ORDER BY element, so the expression is being captured instead of
 	// printing to the SQL output directly. See Dialect#renderOrderByElement(String, String, String, NullPrecedence).
-	: { captureExpressionStart(); } ( expr ) { captureExpressionFinish(); ordExp = resetCapture(); }
+	: { captureExpressionStart(); } ( e:expr ) { captureExpressionFinish(); ordExp = resetCapture(); }
 	    (dir:orderDirection { ordDir = #dir.getText(); })? (ordNul=nullOrdering)?
-	        { out( renderOrderByElement( ordExp, ordDir, ordNul ) ); }
+	    // SQL Tokens without a direction and null ordering can be passed through as-is.
+	    // These tokens could be mapping defined order by fragments which are already rendered via the dialect hook
+	        { out( #e.getType() == SQL_TOKEN && ordDir == null && ordNul == null ? ordExp : renderOrderByElement( ordExp, ordDir, ordNul ) ); }
 	    ( {out(", "); } orderExprs )?
 	;