src/Type/Definition/Type.php
public static function getAllBuiltInTypes()
    {
        if (self::$builtInTypes === null) {
            self::$builtInTypes = array_merge(
                Introspection::getTypes(),
                self::getStandardTypes()
            );
        }

        return self::$builtInTypes;
    }
public static function getAllBuiltInTypes()
    {
        if (self::$builtInTypes === null) {
            self::$builtInTypes = array_merge(
                Introspection::getTypes(),
                self::getStandardTypes()
            );
        }

        return self::$builtInTypes;
    }
Returns all builtin in types including base scalar and
introspection types

@return Type[]