private @NotNull TypeInfo calculateTypeInfo() {
    if (myLhsType.equalsToText(CommonClassNames.JAVA_LANG_STRING_BUILDER) ||
        myLhsType.equalsToText(CommonClassNames.JAVA_LANG_STRING_BUFFER)) {
      return new TypeInfo(true, false);
    }
    if (InheritanceUtil.isInheritor(myLhsType, "java.lang.Appendable")) {
      return new TypeInfo(true, true);
    }
    return new TypeInfo(false, false);
  }
private @NotNull TypeInfo calculateTypeInfo()