Add AST export support

Author: nikic

Zend/tests/assert/expect_015.phpt

@@ -60,6 +60,7 @@ assert(0 && ($a = function &(array &$a, ?X $b = null) use ($c,&$d) : ?X {
             $x = C::${$z . "_1"};
             $x?->y;
             $x?->y();
+            foo(bar: $x);
         }
     }
 }));
@@ -202,6 +203,7 @@ Warning: assert(): assert(0 && ($a = function &(array &$a, ?X $b = null) use($c,
             $x = C::${$z . '_1'};
             $x?->y;
             $x?->y();
+            foo(bar: $x);
         }
 
     }

Zend/zend_ast.c

@@ -2064,6 +2064,11 @@ static ZEND_COLD void zend_ast_export_ex(smart_str *str, zend_ast *ast, int prio
 				zend_ast_export_name(str, ast->child[1], 0, indent);
 			}
 			break;
+		case ZEND_AST_NAMED_ARG:
+			smart_str_append(str, zend_ast_get_str(ast->child[0]));
+			smart_str_appends(str, ": ");
+			ast = ast->child[1];
+			goto tail_call;
 
 		/* 3 child nodes */
 		case ZEND_AST_METHOD_CALL: