Extension that calculates if a UILabel will be truncated depending on its number of lines

UILabel+WillTruncate.swift

extension UILabel {

    func willTruncate() -> Bool {
        guard let labelText = text else {
            return false
        }
        let mText = labelText as NSString
        let attributes = [NSFontAttributeName : font]
        let labelSize = mText.boundingRectWithSize(CGSize(width: bounds.width, height: CGFloat.max), options: .UsesLineFragmentOrigin, attributes: attributes, context: nil)
        return Int(ceil(CGFloat(labelSize.height) / font.lineHeight)) > numberOfLines
    }
}