Creator breaks JavaScript code when auto-formatting QML or JS files.

QtCreator's auto-formatting function for QML/JS code (Tools -> QML/JS -> Reformat File) breaks JavaScript code, whether embedded in QML files or in a separate JavaScript file. This happens on Linux and Windows with the QtCreator version from the official installer.

4 errors occur since at least version 4.8, up to the most recent 4.9:

1. Function arguments are "merged" into one word, i.e. commas and spaces between them removed.
2. Variables declared in for-loops are removed.
3. In pure JavaScript files, the ".pragma library" directive is removed.
4. Pragma directives (.pragma library and pragma Singleton) are removed or broken.

Example:

Before:

function pointOnCircle(center, radius, angleDeg) {
    for(var i=0; i < 10; ++i)
        console.log("test", i)

    var x = center.x + (radius * Math.cos(deg2Rad(angleDeg - 90)))
    var y = center.y + (radius * Math.sin(deg2Rad(angleDeg - 90)))
    return Qt.point(x, y)
}

function deg2Rad(deg) {
    return deg * Math.PI / 180
}

After auto-formatting:

function pointOnCircle(centerradiusangleDeg) {
    for (; i < 10; ++i)
        console.log("test", i)

    var x = center.x + (radius * Math.cos(deg2Rad(angleDeg - 90)))
    var y = center.y + (radius * Math.sin(deg2Rad(angleDeg - 90)))
    return Qt.point(x, y)
}

function deg2Rad(deg) {
    return deg * Math.PI / 180
}