brace the code, the qt creator show the wrong syntax checker notify message

When I brace the code

window.pageStack.depth <= 1 ? Qt.quit() : window.pageStack.pop()

to

{window.pageStack.depth <= 1 ? Qt.quit() : window.pageStack.pop()}

in main.qml. The qt editor's syntax checker will show the wrong nofify message as

window.pageStack.depth <= 1 ? Qt.quit() : window.pageStack.pop()

Which is not an error at all.