Empty string parses as null string

[Mzyxptlk]

{
    "action":"EntityHandler",
    "method":"updateParameter",
    "data": [
        "/path/name",
        "text",
        ""
    ],
    "type":"rpc",
    "tid":294
}

When parsed, "" becomes a null QString, as opposed to an empty QString. The difference is significant. This seems to be an issue in Json::parseString, where the initial result string is created as QString s, rather than QString s("") or QString s = "".

[martinrotter]

Well, this issue report is invalid, since QString("") and QString() are BOTH empty strings + QString() is null string in the same time.

External representation of both strings is "", thus behavior of qt-json is correct.

[Mzyxptlk]

It just took me about 15 minutes to understand my own bug report, so clearly I did a bad job explaining the issue. Here's another try.

Currently, both JSON null and JSON "" become QString(). QString() is both empty and null, as martinrotter said, but that is exactly the problem: JSON "" is not identical to JSON null, so why are they represented by the same value in qt-json?

If Json::parseString initialized its return value as QString s(""), then JSON "" would still be empty, but no longer null. This is the correct behaviour. It allows you to distinguish between JSON null and JSON "", whereas the current implementation does not.

[martinrotter]

IC. So then this bug report is indeed valid and could be fixed the way Mzyxptlk wrote in the first message.