QML url property with empty value evaluates to true in JS boolean context

My expectation is that in Javascript code, a URL will evaluate in a boolean context just like a string would, i.e. the empty URL would evaluate to false like the empty string does. I think there was some version of Qt where this was the case, but I tested back to 5.7 and did not find this to be true, so I'm not sure if it's a regression.

Reproduced as such:

import QtQuick 2.0

Rectangle {
    property url myUrl: ""

    function update() {
        if (myUrl)
            text.text = "evaluates to true";
        else
            text.text = "evaluates to false";
    }

    color: "white"
    onMyUrlChanged: update()
    Component.onCompleted: update()

    Text {
        id: text

        color: "black"
    }
}