How to check if UILabel is truncated?

Question

I have a UILabel that can be varying lengths depending on whether or not my app is running in portrait or landscape mode on an iPhone or iPad. When the text is

Answer 1

Here's the selected answer in Swift 3 (as an extension). The OP was asking about 1 line labels. Many of the swift answers I tried here are specific to multi-line labels and aren't flagging correctly on single line labels.

extension UILabel {
    var isTruncated: Bool {
        guard let labelText = text as? NSString else {
            return false
        }
        let size = labelText.size(attributes: [NSFontAttributeName: font])
        return size.width > self.bounds.width
    }
}